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Warning:  There are some generally accepted techniques archived here.  If you have a question, ask a luthier or repairer before you execute a repair or technique you are uncomfortable with!

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I've got a newer Gibson Historic Reissue, and I am dissatisfied with the nickel parts because they look "new".  How can I age them and make them look 40-years old?


The fumes of muriatic acid (used for cleaning bricks & other masonry) will oxidize the nickel and make it look old. There are two techniques:

1. Pour the acid in a bucket, suspend the part[s] over the muriatic acid with string, and cover.

2. Use a dishpan with a lid. Sit the parts on something like a brick or plastic stand to hold them out of the muriatic acid, and cover.

Don't immerse the parts; the fumes which do the work. The fumes will tarnish the nickel in an hour or so.

Be sure there are no fingerprints on the parts, or they will be VERY obvious in the tarnished plating. Some luthiers do some "creative buffing" when aging parts to put wear in areas that normally get wear prior to using the acid

After you've reached the desired appearance, you should wash the parts, and pH neutralization is a good idea [dishwasher soap works wonders...has a pH of about 12]

WARNING: You're working with acid -- use gloves, glasses. Don't breathe the fumes. Work outdoors and clean up well -- hose down the area with water.

Be careful!  GuitarAttack accepts no liability when you try this or other techniques!


How do manufacturers like Gibson soften double binding to conform to the curves of a headstock? I have tried a heat gun, and the binding usually starts on fire or gets horribly mangled by the time it becomes pliable enough to use and then the window of opportunity before the binding hardens: up again is very brief.


Hot water, the method of choice for plastic bindings. Bring some water to a boil, let it cool a bit, and immerse the binding. Have the water pot available close by, use either the instrument or a separate form to bend the heated plastic, and hold it in place until cool. The water treatment should only be necessary for tight curves and corners. Glue with DUCO cement.


A friend who owns a retail store has a Stella electric, 50's vintage we think. Former repair guy removed the frets for refret but never finished. Now we don't have old frets to measure. Using a feeler gauge the slots seem to be only about .013", way smaller than any fretwire I've found. The smallest at Martin is .018". To compound the problem the Stella has a bound fingerboard. I'd rather not remove the binding. Anyone know where I can find really narrow tanged fretwire?


No takers on fretwire with a superthin tang. However, you make a jig the neck can lay in that has flat surfaces dead even with the fingerboard on each side and set up a straight edge for a fence and use a Dremel in a Dremel router base and simply route out the slots to the size you need. You can always glue in the new frets but Dremel bits are available to give you the exact width you need.

Note: This is similar to the Don Teeter "glue-in" fretting method.

Now for the "I'm so Clever" Award:

Ever build something and want to write your name in pearl right up the fingerboard but know that you couldn't sell it if you did? Well, I have been building these small banjos for the last few months and I got the problem figured out! Using different abalone rectangles for dashes and different sized abalone dots for dots, I have been writing my name in Morse code right up the neck. Only one old time ham operator has noticed so far, but every customer is playing his banjo with my name right there on his fingerboard!


Can anyone recommend what might remove the gunk and sticky from old masking tape on a guitar finish? Its been on there for years and I don’t want to affect the finish in any way.


1.  Try a product called "GooGone". It seems like GooGone is mostly naphtha (cigarette lighter fluid) with some citrus oils to help things along.

2.  Try some lighter fluid. It works for me. Also makes a great wet/dry sanding lubricant.  (This is the Attack method.)

3.  Xylene is cancer causing, as is some lighter fluid (benzene). I use Mineral Spirits as both a tape remover and sanding lubricant. This is what is sold for "paint thinner" in the hardware stores and is basically a light cut of kerosene. But it is safer in many ways than the other solvents mentioned and doesn't evaporate quite so fast. It's also cheap.


This is my first project that includes binding and I have no idea what glue to use. I use Titebond for everything else. Every book I have seen only says glue.

By the way -- this guitar is an old Harmony archtop that I rescued from the dumpster. I reglued the top and back plates, added a cutaway and replaced the fretboard. I thought it would look nice with a gloss black finish and white binding.


I just used Titebond to temporarily glue a bwb nitrocellulose inner lining/Teflon spacer/ebony binding/ sandwich (later filled with paua strips and cynoacrylate). I'm sure that purists are cringing but when sanded out, everything looked great! I have had very good results using Titebond to glue on plastic bindings. I lightly sand the back (glue edge) before applying. It also holds well when sandwiched up to a plastic purfling. Is it just me or has anybody else had success with Titebond?

Answer 2:

Some luthiers dissolve scrap chunks of the (celluloid) binding in acetone and use that as glue--it works, but seems like a lot of effort for very little added benefit. I use DUCO, which is basically celluloid (cellulose

Acetate, actually, which is almost but not quite celluloid) in solvent. When the solvent evaporates, you have an invisible joint. Don't get the glue (DUCO or homemade) on cured lacquer. On celluloid, TITEBOND and hide glue and epoxy won't work, cyanoacrylates might but are dependent on the wood surface for integrity. DUCO is cheap and easy.

Mask off your binding when doing the gloss black finish.


Either I don't know how to find them, or there really aren't that many guitar case manufacturers on the web. Can some of you builders suggest someone?



That's a start. Also try Harptone in New web site but search for their 800 number.


I need to reglue the pickguard on a 1954 Martin D-28. A shop glued it on a few years back and it didn't take. It looks kind of lame, naked so to speak, but still sounds great. I think it may be tortoise shell. I'm not sure, but I believe I need a glue that can be dissolved in case of future partial separation. What's the best glue to use.


Order a pickguard from Martin and specify Tortoise Shell and the year model. You will get a new guard with a glue already on the back with a paper backing. Make sure it will fit the unfinished hole exactly! you may have to trim it slightly to fit exactly. Be very careful and go in small steps and sand the edge as you go until you get it perfect. Clean the unfinished wood with 100 percent alcohol and remove all dirt and oils. Then just peal off the backing and stick it on. I like to rub it for a while to make sure it is seated well. That's it! If you try to reglue the old one with the curled edges, you will be a very unhappy camper.

Martin used a solvent to adhere the pickguard to the bare wood. Then they lacquered over the entire body. I believe acetone is the proper solvent. The pickguard material is celluloid. The problem with acetone is that it will also dissolve the finish on the top. If you choose to do it this way be careful. Incidentally, you may have seen many Martins that had their pickguards applied this way to have developed cracks near the pickguard running parallel to the grain. It is caused by this practice. The wood and the pickguard move at two different rates. The wood responds to changes in humidity by expanding. The pickguard does not. Overall I don't recommend the above method for this reason. Unless you are doing it for commercial reasons i.e. selling a vintage guitar I would avoid it. Put it back on with double stick tape. Stew-Mac sells some really good double stick tape.


I have an older Les Paul that I am re-binding. We've gotten past the how do you get the binding off stage, now we're at the how do you get the binding ON stage. I know the glue to use and all of that, but the Les Paul binding is laminated. My question: Do I laminate the binding first, using something like Stew-Mac's binding lamination jig or do I stick the layers on one at a time? And if I do that, how do I clamp the binding while the glue dries?


My preference is to laminate the binding first and then install it using large rubber bands as clamps. I found some locally at a shipping supply house but they shouldn't be too hard to find. You use a LOT of them so buy more than you think you will need to be safe. A trick that I have used is to soak the binding in hot water to make it more pliable... particularly handy for binding the sharp cutaway area of the body. Some might argue that installing the binding layer by layer is better but not in my experience.

I've done multiple binding one layer at a time and that is not the way to go. Clamping while the glue dries shouldn't be a problem. Acetone dries so quickly, it doesn't need clamping. Acetone alone should hold the binding layers together. By the way -- a good hair dryer or heat gun will also help the bend.


I'm planning to build a solid body guitar in mahogany, I'm trying to locate a supplier. One supplier can supply "Cuba Mahogany". What is the difference between Cuba- and Honduras Mahogany, which is the normal mahogany wood for guitars?  Will the Cuba stuff work as well as Honduras or should I get Honduras for best result?


Cuban mahogany (Swietenia mahagoni) is extremely heavy (about 680 kg/m3)and not usually regarded as an optimal tonewood. (YMMV.) "Honduras" mahogany (S. macrophylla) usually comes from South America these days, weighs considerably less (about 520 kg/m3).

Cuban mahogany also usually sells for 8-10 times the price of Honduras mahogany, in my experience. If the Cuban is cheaper than the Honduras from your source, it may not be the real deal -- there is also African Mahogany (which is cheaper and lighter in color than Honduras, but okay), and Philippine Mahogany (Luan) which is used for plywood.

Stick to the Honduras mahogany if you can get it.

Follow-up 1:

Anyone heard of, or used, "Guatemalan mahogany" for necks on classical guitars? What other names is it known as?

Answer 2:

Guatemalan would certainly be either S. macrophylla or more likely S. humilis. Caoba would be the most likely common name distinguishing it from generic 'mahogany' which as we know can be just about anything.


I'm new to guitar building and rebuilding and I am having trouble refretting an old Harmony Sovereign that is in bad shape. I've removed the finish, sanded and reset the neck etc. and everything went pretty well but I can't get the frets in. I've bought repair books by Dan Erlewine and Hideo Kamimoto that explain the different procedures but just can't do it. Are there any places that sell fingerboards already fretted for acoustic guitars? The fingerboard has been removed from the neck and the bridge is going to be replaced so scale length is open to suggestions if anyone has a particular one they are happy with. I believe the original length was 25 1/8.


Stewart Macdonald sells pre-cut fret boards.

You can't get the frets in because their too tight? or they just won't seat properly? Check the depth of the fret slot, you may just need to deepen it. The tang on your choice of fret wire may just be way to heavy. Widen the slot a little with a fret saw or a Dremel. Or just go to a complete glue in and widen and deepen the slots so the frets will go in and then epoxy them in place. I would try to use the existing board first and try these methods before I would replace the board. The practice will do you good!

Note: This is also similar to the Don Teeter "glue-in" fretting method.


There is a lot of folklore dealing with the issue of an acoustic guitar's "opening up" after being played for some time. There are at least two schools of thought on this, it seems. My own limited experience with acoustics doesn't provide a platform for much of an opinion at all. I should think, though, that the woods, glues and finishes would, over time, change enough to possibly impart some degree of change in tone. What are the thoughts of acoustic instrument builders?


My untested (untestable?) hypothesis regarding this is that when the instrument is first strung up, the wood hasn't begun to creep/stretch very much as a result of the torquing of the bridge. As long as the wood is actively "stretching" it can't vibrate as freely as when it was unstressed or "just" stressed. With time, the creep/stretch diminishes and the new wood shape can now somehow move more freely.

I believe that there are several break-in periods in the life of the instrument. My experience is that for some instruments, the instrument sounds great when it's first strung up, then goes through a "down" stage when it's not as good then comes back "up" again. Others are good from the get go.

I think that some top woods (cedar, redwood) break in easily and others (koa, spruce, doug fir) can take longer. The important thing is to build for long-term stability while making the top potentially light enough to work over time.

My experience is with violins, and I would definitely say instruments change with playing. My first violin had been opened for some work (I don't know what) and refinished, and sat in the closet hardly ever played for eighteen years. When I started playing it daily it began improving (I thought it was my technique) gaining volume and clarity on its lowest notes. It took about a half a year and it was a much-improved instrument.

I have since made a violin which came out pretty good. It had a good tone to begin with, and it too improved with playing. When it was about seven months old I brought it to Vermont to visit some friends an had the opportunity to play it loudly out of doors. After a couple of sessions of wailing away without fear of reprisal by neighbors (I live in an apartment building and my friends live in the boonies on a private road) my seven year old violin started to sound even better, including sounding very resonant even when being played quietly.

The Attack Answer:  It has been my experience that electric guitars also open up and sound different with different finishes.   It is hard to tell the extent of this phenomenon without a clear A/B test, but I believe it even though I tend to be very skeptical of these wild claims.  I am going to experiment with "shaking the dickens" out of an electric for a couple of weeks to see what happens with the tone.  I am also going to build my next electric using only hide glue -- Jim Grainger said I need to check that out.


I need to remove the Indian rosewood back from a Martin D28 herringbone kit that my son and I are building. Everything has been going great -- until now. We glued the back to the sides using our go-bar deck. Everything looked fine -- till we took it out of the jig. Some areas didn't clamp tight enough, and worst of all, the herringbone strip didn't line up as well as it should have with the end block strip. What suggestions can I get for removing the back without cracking this brittle rosewood along the grain? I have not routed a channel for the binding yet.


I don't know if you've had any luck getting the back off your guitar. I haven't had to do that, but I've had pretty good luck removing Titebonded bridges with heat and dental floss (actually I used the dental tape, which is tougher than regular floss). It takes a while, but for amateurs like me it is safer than prying with metal objects. I've used both a blow drier and an iron for heating the glue. The blow drier is probably less likely to burn the wood. I haven't tried it, but I suspect that you could drape a wet cloth over the joint if you wanted to add moisture. Anyhow, once you've heated the joint and found an entry point, you just work the floss back and forth.

Answer 2: 

I have a series of homemade spatulas or lifters made of old clock spring material. This stuff is about 3/4" wide, and I break it off to various lengths then wrap the 'handle' ends in tape for a better grip. The business end is ground to a round 'snout', and I bevel one or both sides depending what I intend to use the things for .

For this job you need something similar, plus some heat and some warm water. I use a little heat iron originally intended for some kind of photographic purpose. This is a small Teflon-covered device with a rheostat to control the level of heat. You can use anything that will put controllable heat where you want it, but be careful. Don't let it get too hot and make the wood brittle. Warm the back up in the area you want to start in, then start trying to get the nose of your spatula between the back and the side somewhere that looks like you have easy access. Where it didn't stick properly would be best. Dip the nose of the spatula in the warm water, and introduce the water into the gap little by little. Slowly you can work the spatula into the gap, and move it along the seam. This is tedious and takes time. I don't know if you have the top on yet, but assume you do, as most books seem to insist on sticking the lid on first. I always glue the back first, because that lets you clean up any glue ooze before the top goes on and it allows you to check that the joint is sound all the way round, inside and out.

If you are lucky enough to not have the top on, you can work at it from both sides of the joint, and that will be very helpful when you get to the blocks and the brace ends. If it comes to a choice of damaging the back or the kerfing, of course go for the kerfing. It is easier and cheaper to replace. If you do make some small splits in the back, they can be sewed up using Super Glue. That stuff welds Indian Rosewood like it was never cracked. As disappointed and frustrated as you must be right now, don't give up. If push comes to shove, the worst that can happen is you may have to make another back, and that is no big deal. It will just cost you a few bucks to get another shot at it and gain a lot of experience. If you routed the back flush with the sides before you started, it would make it easier to get to the joint, but would muddy the water when you have to put the thing back on. I don't know how far off-center you are with the back now. If it is over about 1/8", you could make things much worse by trimming the back first.


Here is a great site for looking up info on trees.  This is a huge database with photos.


What is the formula for the tension on a steel string? The variables should be pitch, length and diameter (for unwound strings) or pitch, length, core diameter and outer diameter (for bronze or brass wound strings).


I think there's a formula for this on David Hurd's website at   Make sure you check out the "Spreadsheet" link for building resources.

Go to the D'Addario web site and download the tension table at


Fender Tweed amps used to have a protective coating - unlike the reissues. Does anyone know what substance was used?


It might be lacquer (given Fenders drive to ship product, a quick drying lacquer would make sense). However, to duplicate the look the general consensus I've heard is to use Zinnser Bullseye Orange Shellac. It can be brushed on and some thinning may be needed.


I’m about to put some pearl into a guitar neck. I have .060" thick pre-cut pearl in the old Gibson Flying Eagle banjo pattern and plan to lay it into a 12" radius guitar fretboard. I’ve been practicing routing on scrap and think I’m about ready to go. My question: What’s the best way to round the pearl to the radius of the fret board once I get it seated?


For the pieces that cross the center line, shim your Dremel (you do have a Dremel, I hope) router base so that it rides perpendicular to the fingerboard radius, and cut the mortises so that they are shallow along

the edges and yet allow the inlay to seat almost dead flush with the wood in the center. Make sure that inlay will seat perpendicular to the radius, not tilted in any direction. Glue the inlay in place, and then carefully level it with the fingerboard wood. To do this, use a double-cut mill file and a hard sanding block with 80 grit sandpaper.

When the pearl is just about flush, go to 180 grit paper, then 200, then 400, then 600. For the pieces that don't cross the center, skip the shim and just rout the mortises to about 95-98% of the inlay thickness, glue in place, and level as above.

One additional suggestion.

You can glue a piece of square profile toothpick or scrap wood to the top of the pearl inlay with just a dot of glue so that it sticks out on the sides. This acts as a stop on the fretboard in case you got one of the inlay slots too deep and keeps the inlay from going below the surface level of the fretboard. Once the inlay glue is hard you can just snap off the little stick.

Another suggestion for marking the fretboard. Stick the inlay in position with some double stick tape, the masking type is quite strong. Then trace around it with a carbide tip awl or a narrow point Exacto knife tip making just a light line on the fretboard. Don't go back over or you will get conflicting lines. Pop off the inlay and then rub some powdered chalk (lumberyards have it in various colors for refilling chalk line containers) into the area and blow off the excess. This will leave the scribed line with the chalk showing quite nicely and make it easier to follow when routing.


Been a long time since high school electronics and it may be too simple for me to see. Where on a pedal would I measure the draw, if I've got no power to it or do I assume 9v? And where would these measurements be taken? Alternatively, would I measure across the in and out 1/4" with a 9 volt hooked up to it - is the battery stabile enough for a good measurement? Won't the pots vary the resistance depending on where they're set?


Try disconnecting one tag of the battery connector and connecting the ammeter, one side to the battery, one side to the connector so that the ammeter is in series with the battery. You could use croc clips to hold the probes in place.

Put the pedal in a working situation and measure the current drawn. If you want to, you can try altering the settings to see how much difference it makes. With a device driving headphones or a loudspeaker, gain can make a big difference to current drain but on a device delivering at low levels into a guitar amp, there shouldn't be much change.

The capacity of the battery in amp/hours or milliamp/hours will probably be printed on the side. Watts = Volts X Amps so you can pretty easily calculate how long the battery should last.

Check that the power switching around the output jack is working. If its drawing current continuously (i.e. battery not disconnected from the electronics when you unplug it) that could also produce the symptom of short battery life!


Does anyone have a tried-and-true method of drilling the string ferrule holes in Teles and hardtail Strats? I never seem to get them exact on the drill press and the router spacing is uneven.


I've had the same problems. I bet the manufacturers drill the 5/16th hole on the back first then, the smaller holes for the strings. As a fix, I wonder if a metal drill guide( 6 accurately aligned holes) would help keep a narrower bit from bending and following the grain?

This may be too obvious, but you need to use a brad point bit. Less obvious are varying qualities of brad point bits, some drill truer than others.

Last, how accurate is your drill press set up and how true is your drill press table? When shopping for a new press a couple of years ago, I took a straight edge to test the tables and every table was out by a mile. I bought the best press I could afford/find and took the table to a machine shop to be re-surfaced on a lathe.

I drill (8) 1/4" through holes in every body I build. I use a steel template to guide the holes (no drill guides, they'd be nice, but you can get hundreds of holes out of mild steel if you're careful). The holes on the back of the body need to be right on, because two of the holes at opposite ends of the body need to fit onto pins on steel templates, so they can't be more than .010" out.


Is there a way of establishing the relative phase of two pickups before wiring them up? It can be a bit of a pain to wire up a strat type guitar only to discover the pickups are out of phase and to have to remove the strings and scratchplate, rewire and reassemble.


Set a DIGITAL ohmmeter to the proper range to read the resistance of the pickup. Connect the hot lead of the pickup to the red lead of the meter and the ground lead to the black lead of the meter and observe the ohm reading. While the pickup is still connected. SLOWLY move a screw driver of similar metal object that is attracted to a magnet from about 20" away towards the pickup and note if the ohms go higher or lower. Repeat with the other pickups. They should all go higher or all go lower to be in phase regardless of magnetic orientation. If one is reverse you have to reverse the wire connections when installing.

Two pickups each with the same magnetic polarity and both wound clockwise (or both wound counter-clockwise) relative to ground will be in phase with each other. Reverse the magnetic field of one or reverse the direction of winding to put them out of phase. Reverse both and theoretically you've put them back in phase again but in practice,unless they are evenly matched, they may not sound "quite right."


I'm going to buy Stew-Mac's hot rod ( two way adjustable) for a 24 fretboard bass 34" scale. The rod is long 24" and the fingerboard about 25.5". The question is how far from the nut should I place the rod?


Put the truss rod on the neck and figure out where you want the nut (of the truss rod) to be so that it will be accessible. Of course, this will depend on whether you are making adjustment at the heel end or the nut end. Assuming this will be a bolt-on neck, with adjustment at the heel end, you'll want the end of the truss rod nut to be approximately flush with the end of the neck.

Once you've figured out where you want the truss rod nut to be, it will be clear where to rout the channel.

Another option if you do not already have on the headstock overlay is to just rout the channel all the way through from the body end right on out the headstock end. Then position the rod and mark for what you want. Then come back and fill the excess slot with ebony or other hardwood or those short scraps of graphite bar that are hanging around. Since it is a double action rod you just have a flat-bottomed slot so you can get away with this.


Can anyone suggest a way to protect a signature on a bass / guitar? It's done with a permanent marker, but aside from making a clear pickguard to cover it, I wonder if there is any other way to preserve it.


It depends a bit on what your resources are and your skill level in spraying.  Test your technique on something other than the guitar/signature until you are comfortable. Mask off the guitar except for the signature area. Clean the area gently with soap and water (solvents will cause it to smear).

There are two approaches: Clear nitro lacquer and waterbased lacquer. Nitro must be sprayed on but waterbase may work just brushed on, but brushing has a high risk of smearing the signature.

Water based is the lowest risk. But harder to get as you have to buy it from a finish supply house or Woodworker's store. And you will get enough to completely finish several guitars. Spraying this will likely not cause the signature to blur or run. Spray one or two light coats and let dry. You could spray nitro over this after it is cured (two weeks) to get a better sheen.

Nitro lacquer will work well, but if you put it on too wet the signature will "bloom" as it dissolves in the lacquer and get fuzzy and blur. So practice your technique if you do this. If you are going to buff things smooth, better put on 3 or 4 coats.


My Gibson Les Paul's selector switch keeps working loose and starts turning. It is hard to tighten this round switch-nut with my bare hands, and even if I do it loosens again in a week or two.  On the other hand, I am afraid that the use of pliers would damage the nut, or just rip a pickup-cable from the switch. Is there a better way to do it?


Stew-Mac has a special wrench just for this. It fit's right over the switch, much like a spark plug wrench. It's called a toggle switch wrench, part number 1699 and costs $24.98.


I'm going to route pickup cavities on a guitar I'm building. Are there any tips for routing I need to know about?

Answer 1:

1. Make sure your pattern is large enough to support the router base. Tipped routers make for screwed up work.

2. Don't start the cut in wood, but get the router up to speed and then enter the wood slowly and carefully. This will make for a more relaxing router experience.

3. Use a new bit and take as shallow a cut as possible on the first cut to avoid chipping out the curly maple.

4. Running with 2 bearings on the shank will provide you with insurance against the bearing self-destructing and ruining your work and the pattern (especially plastic). This is a good 5-dollar investment. I've ruined 2 Plexiglas trem templates this way.

5. Practice on scrap wood first.

6. Don't overtape your template if you are using double-sided carpet tape. That stuff really holds, but use enough to hold the template down. You also don't want to forget that the tape adds to the thickness of the template. If you set your depth by turning the router upside down, setting a template on it, and measuring to the end of the bit, you will actually get a shallower cut once tape is factored in. Better than deeper, but still a problem if you don't notice until assembly time. Measure your actual cavity before you decide you're done!

7. Wear safety glasses and hearing protection, and have a shop vac handy to suck out the chips. The heat build up helps to dull the bit.

8. Wait for the router bit to stop before you remove the router from the work.

9. Don't rout when you are tired and or drinking!

Second point.

When using router bits with templates for routing, pre-drill waste out with a Forstner bit leaving only a small amount of wood to clean up with the router. The router bits will stay sharper longer.

Answer 2:

It is always a good idea to order the hardware first because there are subtle variations in even "standard" sizes. Then just take the measurements directly off the pickup or the ring. Do it on full sized paper. Remember that the hole for the flange on the pickup that receives the ring bolt goes deeper then the pickup body itself. Another thing to consider is that humbuckers have a sharper radius on the corners than the common 1/2" router pattern bit. In a pinch, I will drill those corners with a 5/16" (8mm) bit before routing to keep them crisp.


Anyone have any ideas how I can fit my Schaller strap locks? I've unscrewed the original strap button screws & tried to fit these new strap locks...problem is that the new screws are too thin!


Put wood glue on a matchstick or toothpick and jam it into the hole. Allow the glue to dry complete, break it (the matchstick or toothpick) off flush with the guitar body, then screw in the strap lock.


How can you enhance the birdseye in birdseye maple and still keep the light natural finish or use a light color (or other) finish?


See Finishing Guru Jeff Jewit's site   and click on "Early American Maple Finish".


Being a longtime bassist and humbucker fan, I don't often have to deal with the hum and buzz monster common to single coil pickups. However, I currently have to deal with the guitarist in my band, whose Mexican Strat is delivering some pretty bad buzz in one club in particular.

I have done shielding with copper foil on my own instruments here and there. Is there any hope of improvement to be gained by shielding the heck out of his Strat, or is it simply an incurable pickup characteristic?


Check out this website for some good information on shielding and re-wiring Strats and other guitars for maximum hum reduction:


I read the $5.00 pickup article at Harmony Central. I'm wondering if anyone has tried to use this on an electric?


The piezo elements this post is talking about are available from Electrosonic for about a buck each without the plastic housing etc. Many luthiers have been using them as pickups for cash-strapped clients since the late 70s. They work fine if you put them through a pre-amp, and can be used in tandem for more 'grunt' and greater depth of sound. Most usually stick them to the underside of the top near the bridge plate with double-sided carpet tape. No one is sure what they sound like on an electric; however, the consensus is that to get a good acoustic sound from a solidbody, you should probably use a bridge-mounted system made by Fishman or Christian.


I have a "tinny" sounding Strat. Something on the guitar is not letting the strings vibrate in the normal way, sort of like the pickup being to high. It's almost like when you pluck a string and put your fingernail or fingertip just close enough to make the string make a sitar like sound. The note doesn't ring clear as the other ones do,


It really does sound more like a nut, saddle, or fret problem.

If it's not any of those, check all the hardware, something may be resonating sympathetically -- check all the set screws on the saddle pieces, the switch, etc. Also a loose truss rod can resonate, although that seems sort of unlikely in this case. If it's sympathetic vibration, the same pitch will usually make it happen, independently of where it's played -- try playing the same note 4th string 5th fret, etc, see what happens.

Another thing you can try is increasing the break angle over the nut -- press down on the string between the nut and the tuner, see if that helps the buzzing.

It really does sound like it's in the nut, or first fret -- it only takes a thousandth of an inch or so to make the difference between a guitar that plays and sounds good and one that doesn't.

Without the right tools, it's going to be a lot harder to fix this. The simplest quick-and-dirty fix for this might be to just loosen the neck bolts and slide a thin shim into the front of the neck pocket (the "front" of the neck pocket being between the bolts and the headstock), and tighten the neck bolts. That's not the best repair, but it might get rid of the buzz until you can acquire the tools.

If by some chance you have a Strat with a tilt adjustment, back that all the way off first before trying the neck shim.


I'm about to embark on laminating a nice bookmatched set of flamed maple onto a naked body (electric guitar) & need some advice. First, the wood has, in the several months since I bought it (1/4" thick) bowed along the grain. Any suggestions on how to flatten it out? Should the two pieces be glued together before laminating it to the body? What glue? What type of glue should be used in lamination? Any other "tricks of the trade"?

Answer 1:

If you resawed the lumber yourself sometimes the moisture content becomes uneven on the sides of the wood and it has to acclimate. Resawing also may release stresses that may be built up inside the lumber by improper drying. In many cases, the warp has to be jointed/planed out. To get to your questions, I prefer to glue my laminates together first, thickness them, and then glue to the base material with a veneer clamping type of operation. I don't have a veneer press, so I use many clamps and flat cauls. I use yellow glue for both glue ups.

It is also common that if the plates are laid out flat and are not at perfect equilibrium or if the shop humidity or temperature shifts, the top surface will either expand or contract as it loses or gains moisture causing a cup or bow. Stand them on their edges and they should flatten out it this is the case.

Answer 2:

I've tried several methods recently for gluing up laminated tops for solid body instruments. Originally, I glued the 2 halves of the top together and separately, the 2 halves of the back down the centerline. The biggest issue there was how to clamp the center of the 2 when finally matting the 2 large surfaces. I tried minimizing the distance by bandsawing off the waste to within 1/2" or so of the external profile before gluing to make the witness line that showed invisible.

While the edge was ok, the middle was obviously crowned from glue that was trapped under it and not clamped.

My more recent method, perhaps obvious to others already, was to glue the top to the back on each of the respective sides. This allowed each half to be run through the jointer, making an exact line in the center. I also waited to finish sand the front and back faces to thickness until after gluing them up. This allows clamp marks, minor flatness variations etc to be eliminated after gluing.

I had hoped to sand the entire blank after the halves were glued up in the Delta sander but haven't tried that method yet. Size wise, it should handle it but it will require some time to get it done. I'm happy with the 2 part method at this point.

Answer 3:

I learned another painful lesson last weekend regarding heat and PVA glue.  I bought an IR cure lamp on the recommendation of a body shop friend. It GREATLY speeds up the cure time on all solvent finishes. I tried it on some samples and even a headstock of a laminate neck. No problem and the lacquer dried very quickly.

I tried this on a full body last weekend and it split the center seam open. There was certainly some locked in stresses as the gap was over 1/16" in the center. I was pretty irritated as the body was ready for it's final clear coat after much work doing 3 different dye steps.

The manufacturer gives recommendations for distance/time for various materials. I may still try using it but for shorter times periods (I used 20-25 minutes) and greater distance (I used 20"). The cost of these isn't terrible: $199 for the stand and a 36" single lamp unit with a reflector. The problem is certainly that metal works better than wood for this cure method!!!


Are there any tips for gluing cocobolo?


Use regular Titebond. You must clean/wipe the surface to be glued since it is such a resinous wood. Use naphtha followed by mineral spirits or alcohol. This may take several passes until you are not getting so much color off.

For a back seam, try using epoxy. If you have a real tight seam thick, try super glue (CA). This is such a thin joint that will never have to be released, the more permanent glue is OK here. You can still use the Titebond for the back joint strip inside though.

Wear gloves and a mask when sanding this wood -- a real mask not just a dust mask. There are many that claim toxic reactions to it. Proceed with caution until you know whether or not you are allergic to it. Once finished it is fine. However, it does tend to bleed into a finish too, so be careful if you have maple binding or such.


Any suggestions on how to finish a guitar neck? It is a maple neck with a maple fingerboard - what should I use?


1. Warmoth actually has some information on do it yourself finishing of their necks on their website. I do know that they will not warranty the neck if it finished with an oil finish. They recommend a "hard" finish.

2.  (From Mr. Bill Lester): Here is what I wrote about it.


Up until now I've used spray cans to spray nitrocellulose. However, this time I'm going to give it a shot with the Preval spray unit and use nitrocellulose out of the can. One question -- what is reducer? Everywhere I look to order the lacquer, I also see reducer... do I need it? If so, what ratio should I be using in my painting?


(From Mr. Bill Lester). Reducer is thinner. Hardware stuff like Crown works just fine. And perhaps to further dispel a myth, absolutely wonderful results can be obtained with aerosols. Here is an example I added to my site.


I am in the process of sanding down a maple neck for final finish. This neck has a large number of dings and I was wondering if there was a wood filler available that I could use on maple with unduly hiding the grain pattern?


1. Maple doesn't require any filler, and I suspect that if you use it the appearance will be weird to say the least. As far as the dings go, try steaming them out. Take a clean white cotton cloth, wet it with clean water, cover one of the dings with a corner of the wet cloth and apply the tip of a soldering iron or gun to the cloth directly over the ding. The iron will boil the water rapidly, causing steam to go into the ding, swell up the compacted fibers and puff the cells back up. It will take 3 or 4 applications of water and heat, but you should be able to raise most dents to within 10% or so of their former glory. Be careful with the heat, as you don't want to scorch the maple.

2. Another way to do the same thing is to use a damp Q-Tip for the moisture source. This helps you to be more precise -- the less junk in the way the better. I also tend to wet just the dent this way rather than getting a wet cloth all over the guitar or neck.


I was replacing the knobs on my 1987 B.C. Rich USA Series Mockingbird, which are split shaft, and I broke one of the shaft halves of the tone pot. So far I have not been able to locate a matching pot or capacitor. Here is what I can tell you: The pot is quarter sized and fits a 5/16 size hole and the threaded portion is 3/8 long. The shaft is knurled, fine I think, and is about 5/16 long. The following is written on the bottom of the pot:


    06 K

The capacitor is a small, rectangular, and dark green in color. It has the following written on it:


    [R] P

The brackets I put around the R are really a square, and there is a dot under the square.

I would really like to replace the parts with ones like the original if possible so any help would be greatly appreciated.


1. There is a good chance that it's a 500K pot (50 with 4 zeros after it). There is a good chance that's a .022 uf cap (22 with 3 zeros after it but measured in picofarads). 22000 pf = .022 uf. By the way, uf is the same as mf.

2. For replacement, the cap is easy. Even Radio Shack probably has that. Buy a Mylar .022 cap (usually a little green thing). Voltage rating is not critical (That's probably what the 50 is in the part number)

The pot should not be much tougher to locate. Try a 500k 'audio taper' from Stewart-MacDonald's Guitar Shop Supply


I purchased a plastic hardshell guitar case for a Jackson 'Kelly' guitar for $10. Unfortunately, I don't have that particular guitar. The case is rectangular black plastic. On the inside is the 'standard' black fake fur covering white molded Styrofoam. I'd like to 're-fit' it for an ES-335 style guitar. The dimensions of the case (length/width) are fine. How can I 're-fit' the inside?


Styrofoam is cheap and easy. Go the building supply and pick up a sheet, or cruise dumpsters looking for old packing foam, depending on how cheap you are.

When I built a "bus proof" case for my niece's upright bass, I fitted up the interior from Styrofoam (mostly) and a bit of upholstery foam (foam rubber-ish stuff). Hot glue was exceedingly useful in combination with getting a good fit on the pieces in the first place.

A hot wire is nice for getting a clean cut on foam, but it's not needed if you are going to cover the foam up with fake fur or velvet.


What type of finish is used on Lowden Guitars?  (Note:  I thought the steel wool technique was interesting -- John)


From the Lowden Discussion Group.

1) The finish brand:

"The lacquer we use is Beckers/Kemira which is formulated in Europe and distributed from England to us in Ireland. We have tried other nitrocellulose lacquers and there isn't a big difference, it just has to be specified to not be high gloss; i.e., it needs some matting agent, but the biggest factor of the satin finish is the steel wool process. Before the guitars are finally wet and dry sanded with 1200 paper and then steel wooled, they are very glossy."

2) Now, how they finish the finish (!):

"We do finish the guitars with nitrocellulose as you say; however, if you look closely you will see, running along the length of the grain, very, very fine lines --almost like the brushed effect you see on brushed aluminum. This is achieved after all the finish coats of lacquer are applied by rubbing, very carefully (in a straight line), but very vigorously, with fine steel wool. This gives the guitar a nice warm look (i.e., its intention is to tone down the glossy effect of the lacquer, and ours is actually formulated to not be high gloss! Quite the opposite of most other companies.

This also gives the Lowden a very warm feel in the hands of the player. It is usual that the neck tends to shine up due to playing and bodily acids etc, but you won't see this on a new Lowden.

We don't suggest you re-steel wool the instrument as the bridge will be in the way; and you need "0000" steel wool, which believe me varies in quality from make to make. We use "Liberon" which is French."

(Remember -- GuitarAttack is about playing, too…. I couldn't pass this one up.)


I am getting ready to build a speaker isolation cabinet (SIC). This is to mic a guitar speaker, without worries of isolation. This will be used both live and in the studio.

When we make good speaker cabinets, isn't one of the first requirements that no dimension be equal to or a multiple of the other two? In building a studio, we learn that it's best if we eliminate as many 90 degree angles as possible, yet the interior dimensions of the Demeter SSC-1 appear exactly that: square! So, my question is should an attempt be made to design a SIC that does not have all right angles and square dimensions?


As for the questions, try --

This is a very comprehensive web site! The testing data is awesome.


I just got a home built drum sander. It's a nice unit for my needs, but I want to put a stronger DC motor on it. It had a 1/2 horse before but it bogged down occasionally. Can anyone give me advice on the best size motor for this 4" diameter drum sander?


You should use a 1.5hp minimum. You could still bog it down, but will work fine for light passes.

Question: How do you create a sunburst finish without spraying? Can you do it with shellac?


Try alcohol-based tinting dyes as used for stains, then mix it into Bullseye shellac; get a quart and mix a dab of the stain into half a yogurt cupful of shellac. Remember - you're just going to wipe with a rag so you don't need much. If its too thick you can add lacquer thinner to thin it. Tape off the binding with masking tape-- it will save time when scraping the binding with a razor.

Use a cotton rag to rub the color into the wood. Work from the inside of the guitar out toward the edges. Apply lemon yellow, then Aztec gold, then fire red. Use the gold to transition between the colors. When dry peel the masking tape and scrape the binding. Smooth the binding scrapes with 220 grit 3M production-cut gray paper. When complete, spray with clear lacquer to set the sunburst.  Once set, you're ready for clear coating.

Question: How do you stain a maple neck to match a mahogany body?


Practice with the tints. Get some maple blocks or chips and take your time thinning until you get it right, first with a brown then with red. As a technique, I'd use a Minwax red-brown stain(oil-based), wipe, and allow to dry 2 days. Then use 4 swipes of 120 grit paper to scuff it. Follow with a dark red alcohol stain and dry immediately. Continue to tint with the red.

The stain tips were passed via Gar from John DiTripano who worked for Gretsch and Gibson. He has a shop in Alhambra, California called John D repair and does repairs for Pedrini's Music.

Question: What else can you use shellac for?

Answer: Shellac is important because the solids are much finer and penetrate better than lacquer. I use Bullseye spray shellac on the cones of my Celestions if they are too warm or dull. This method is very safe - try it. I cut open pre-Rola greenback speakers and repair the voice coil breaks. I reglue the sliced cone and stabilize the whole thing with spray shellac. I buy blown Celestions for $5, or get them for free, then get them going again without reconing.

Question. What does the Ohm-value of a potmeter really mean? I know it's the impedance, but what does it do with the signal/sound? What happens if I increase or decrease the impedance?

Smart-Alec Answer:  Pickups have many, many windings of very thin wire. So many in fact that their resistance across their coils is quite high. Perhaps 30 to 50 Kilo ohms. If you wire a pot of low resistance across it, it will load the tiny amounts of voltage the coil generates when you vibrate a metal string in front of it. It is like this; if you place two resistance's in parallel the total resistance is less than smallest of the two. In some cases, the impedance's should be higher than the coil being used so as not to present a mismatch to the coil. Many factors come into play. It all depends on how the circuit is wired and what the impedance's of the coils are used, how the coils are wired together, whether in series or parallel or even series parallel. There is no set rule for all components. That is why I build strictly acoustic instruments.

Question: So a 250K pot ranges from 0-250K 0 Ohm is full volume and 250 is the lowest volume..or? Of course I understand the concept of resistance in a circuit, but I'm not still sure why a humbucker should have a 500K pot while a single coil uses a 250....and I'm not sure I know why other pot's use other ohm-values...

Answer:  Mr. Bill Lawrence states that the easy way to figure the right pot for a pickup is to take the inductance of the pickup (in henries), multiply it by 100, and there you have it. Since a Strat pickup's inductance is around 2.34 henries, it should have a 250K pot. Since a PAF humbucker's inductance is around 4.4 henries, and requires a 500K pot. You have to have an LCR meter to measure inductance, and they are expensive. In my experience, the value of the pot is really not that critical. I recommend experimenting with values -- you may find that the 1 meg pot is a good choice for all applications. In my opinion, you are not going to hear a big difference between 250 and 500k pots. As for the 300k pots Gibson used for their tone controls -- go figure. Maybe it was a compromise between 250 and 500k, or they got a big lot of them cheap.

Question: Is there any way to easily remove frets without the Stew-Mac fret pullers?

Answer 1: The luthier I used to work with used nothing more straight toenail clippers with the face ground flush. It doesn't take a lot of force - or it shouldn't. This isn't a muscle job, it's a finesse thing.

Answer 2: The StewMac special pullers are really just a set of large end-cut nippers that have been ground flat on the outer surface. I bought a $10.00 US pair of good nippers and then just ground them down to be flush-cut using my belt sander. This gives it a nice flat surface so that they approach the fret without digging in the board. Be sure not to grind too far, just enough to get them flush.

Answer 3: Well, no matter how the frets actually get pulled, I believe heating them with a soldering iron is essential to loosen any glue that might be under them, and virtually eliminates the chances of the wood chipping as the fret is pulled out as long as you're careful. You might want to get a flat, wide soldering iron tip and grind a groove into an edge to hug the fret better and lessen the chance of slipping off the fret onto the fretboard.

Question: I bought an ebony fingerboard for a bass project. The problem is that the ebony came roughly sanded, you can see the lines of the belt sander on it. What do I do? More sanding? Wax? Oil?

Answer:  I have made a couple of guitars with ebony fingerboards, and as long as you get the sanding really smooth, you don't really need any finish.

Start with around a 120 grit paper, and work up to 400 grit. I find the red Aluminum Oxide paper works best, especially if you can get the cloth backed stuff. It comes in rolls (presumably for belt sanders). Take care not to sand the fingerboard into an odd radius! I have a block with a 12" radius machined into the bottom, so I can be sure the radius stays accurate.

I do the final polishing with a product called Micro Mesh, which is used for polishing plastic (such as aircraft canopies). It's basically a very fine abrasive cloth, and I find that going up from 1200 to 6000 grit gives a glass like polish to ebony, wenge and similarly hard woods.

The black wet or dry type of paper doesn't really work very well on wood, and it leaves black marks on light timber.

If you really want some kind of finish, I use teak oil. Just make sure it's completely dry before you string up the guitar, or you will kill the strings.

Question: I just finished installing all 22 frets into my bound fingerboard using the Stew-Mac fret press arbor in my drill press. It worked like a charm - all 22 in in a little over an hour (including hand bending time). I undercut the tang with the Stew-Mac fret tang nipper, so only the bead is overhanging the edge of the board.

Now, I want to superglue the overhang down to prevent it from lifting, and I would like some more details on how. I plan to mask off the board at either side of the fret with electrical tape to prevent messing it up (other suggestions for protection? wax? how would I get that off again?), and then apply some glue under the fret, let it soak in, and hold down the fret with a dowel for 30 sec or so until it dries.

Question: Do I cut the excess fret overhang before gluing or after gluing?

Answer: Cut the frets before you glue them. The torque of the clippers or file will damage the glue joint. You may also find that if the fit is good you don't need to glue them at all. There isn't much unsupported fret wire after you have beveled them back. If you do superglue them in, use paste wax to protect the fingerboard, then use a toothpick to let a very small amount of glue wick in under one side of the fret. Then wipe the area quickly with acetone (which can damage plastic binding -- be careful). Don't use accelerator -- some types will cause the binding to melt.

Question: Can someone explain why the human body will stop an electric guitar from humming? Is there anything I can do to the instrument to simulate this condition and thus eliminate the hum? I have tried all sorts of grounding things, but some guitars do NOT want to be quiet without a human touch.

Answer: I recently read and tried a method of hum elimination that worked pretty well although it is a lot of extra work. Basically, the shield grounds are isolated from the signal ground by a big cap. In this example is was 1.0 uf at 400v -- a good-sized one. This example was for a Strat and the author connected a large round terminal lug to the aforementioned cap and used it as the washer for a pot. All of the shield grounds were attached to the same spot. The other end of the cap went to the signal grounds coming off the jack.

The body cavity and back of the pickguard were well shielded. Essentially this works because the signals and shields don't create ground loops -- or at least less than they usually do. Be sure the cavity shielding is connected to the cap at the right end. I used copper tape from StewMac and folded it over the edge a bit so the pickguard shielding touched. Give it a try.

Answer 2: The ground wire is connected to the strings, so when you touch them (or any metal part of the guitar for that matter) the hum goes away, as you are acting as the final ground link. Better shielding should help to a certain degree, by blocking out the radiation that causes the hum (conductive painting of the cavities, no long, unshielded wires).

Answer 3:  You can probably get away without using a ground connection with a humbucker-equipped guitar, but single coils will be tough.  Check out for Wiring 101.  There is some great information on there.

Question: I need to reglue the pickguard on a 1954 Martin D-28. A shop glued it on a few years back and it didn't take. It looks kind of lame, naked so to speak, but still sounds great. I think it may be tortoise shell??? I'm not sure, but I believe I need a glue that can be dissolved in case of future partial separation. What's the best glue to use?

Answer 1: Martin used a solvent to adhere the pickguard to the bare wood. Then they lacquered over the entire body. I believe acetone is the proper solvent. The pickguard material is celluloid. The problem with acetone is that it will also dissolve the finish on the top. If you choose to do it this way be careful. Incidentally, you may have seen many Martins that had their pickguards applied this way to have developed cracks near the pickguard running parallel to the grain. It is caused by this practice. The wood and the pickguard move at two different rates. The wood responds to changes in humidity by expanding. The pickguard does not. Overall I don't recommend the above method for this reason. Unless you are doing it for commercial reasons i.e. selling a vintage guitar I wood avoid it. Put it back on with double stick tape. Stew-Mac sells some really good tape.

Answer 2: Order a pickguard from Martin and specify Tortoise Shell and the year model. You will get a new guard with a glue already on the back with a paper backing. Make sure it will fit the unfinished hole exactly! you may have to trim it slightly to fit exactly. Be very careful and go in small steps and sand the edge as you go until you get it perfect. Clean the unfinished wood with 100 percent alcohol and remove all dirt and oils. Then just peal off the backing and stick it on. I like to rub it for a while to make sure it is seated good. That's it! If you try to reglue the old one with the curled edges you will be unhappy with the results.

Question: What is the best technique to clean the gunk off of an older fretboard?

Answer: On unfinished boards, there is nothing better than a light coat of lemon oil wiped on, and then worked off with 0000 steel wool. Some then follow with carnauba wax to seal the board and make future cleanings easier.

On finished boards, watered down Meguiar's #7 on a paper towel works. Naphtha works well too. Avoid the steel wool, though, unless you want to rub the finish back to gloss.

Subject: Stud removal

Question: I'd like to reuse the bridge and tailpiece from an old guitar in a new guitar I'm putting together. This means I have to remove the studs (bushings) that the mounting posts screw into. Is there an easy way of doing this without harming the surface of the instrument?

Answer 1: Get a long screw that fits into the stud, preferably made of hardened metal, and preferably with a or a hex key head. Drill a hole in a piece of wood a little larger than the diameter of the screw. Put the new screw through a thick washer that won't let the head pass through the wood. Put the screw through the washer, through the wood, and into the stud. Turn the new screw until the stud pulls out. To protect your old guitar's finish, you could place some felt or leather between the wood and the surface.

Answer 2: Place a bolt into the stud hole so that the stud is pushing down on the bolt ( essentially pushing the bolt into the body wood) . When the stud is tightened, it bears on the bolt which can't go anywhere and the insert comes up. This is similar to a "steering wheel puller." Caution: If your guitar has a cap top, there is a slight possibility that the post bushing is a "T" shaped item, with the wide part of the "T" on the underside of stud mounting hole. If this is the case, pulling the stud insert will also pull out large chunks of wood.

If you suspect this might be the case you can check the stud. To check, drive a small pin along the edge of the bushing down into the guitar to whatever depth satisfies your suspicion. If you strike metal, you're not going to be able to safely remove the stud insert without removing the cap top.

Question: I have a problem with my bolt on J-bass neck. When I remove the neck to adjust it (which is not too often) - the screw holes in the neck get slightly stripped, so I have had to dowel & re-drill more often than I like. Has anyone solved this problem by using threaded brass inserts in the neck heel?

Answer 1: Heli-Coil (brand name) sells steel threaded inserts in most automotive stores. You use a special tap (theirs) and just thread in the inserts. They come in sizes up to 1/2" and work great in hard maple.

Answer 2: Check the Fender Japan site -- their high-end Strats have a similar setup.

 Question: What is the accepted tolerance in the fret spacing accuracy before intonation will be compromised.

Answer 1: (A friend responds): I measure mine to the 1/100 of an inch. Since most kerfs for fret slots are .22 of and inch minimum, expecting a slot placement at better than 1/100 " tolerance is not practical without a precision machined gang saw. I mark mine with a very sharp carbide needle and try the best I can to cut dead center with the aid of a magnifier. But I know I'm kidding myself if I think that I have 100% accuracy at 1/100. I am, however, very satisfied with the intonation, of course with the proper bridge compensation, using this method.

Answer 2: Stew-Mac offers pre-slotted fingerboards and a cool miter box with templates for slotting fingerboards. Their slots measure .24 inch. Think about that -- how precise can you be with that wide of slot?

Question: What are the acoustic affects of vibration on tone woods.

Answer: (Al Carruth) sends: This has been a huge can of worms for years. The experiments are very difficult to do, and there always seems to be a lot of room for dissent and interpretation.

Carleen Hutchins published a paper a year or so ago in which she gave 'before' and 'after' measurements on a 'cello, two violas and a violin that show measurable changes in the response after playing. She feels that the walls of the box get more flexible.

I did one experiment where I vibrated a strip of wood for a month, and measured it before and after for several properties. the only real change was in the 'damping factor': it absorbed more sound after a month of shaking. It's suggestive, but hardly a statistically valid sample.

I've been taking spectral measurements of every guitar I can for the past couple of years. Most of the older ones have a broader peak around the main top mode resonance, and I associate that sort of a peak with a 'full' tone. Of course, you can't know what they were doing when they were new, but I have reason to believe that at least some of them (like the Ovation) had a narrower peak and a 'thinner' tone when new.

I think it's probably in the nature of the question that you will have a hard time convincing the skeptics. It seems logical to me that there would be some change; why should guitars be the only thing in the world not subject to entropy? The nature of the change may be hard to nail down, and the musical consequences will be ever open to debate.

Alan Carruth / Luthier

Answer 2: I believe there was an article in the Feb 1997 issue of "Acoustic Guitar" magazine where they reviewed a device (essentially a high powered loudspeaker/shaker table) which you could strap a guitar to and it would essentially play it and break it in. The reviews of guitars that were processed with this appeared to indicate that it made a positive difference.

Question: Cocobolo

I just bought a plank 11" wide, 2" thick and 12' long. There are a couple cracks but it is clear all the way through. I'll start slicing it up to age after I get finished with an upcoming relocation. BTW, have you tried anything to keep the wood from oxidizing? Its mature deep brown is very nice but it would be cool if you could keep that orange.

Answer 1: I have built 10 guitars from Cocobolo. I don't think there is a better all around wood available today in terms of sound and beauty. A lot of the problems associated with Cocobolo are highly exaggerated, especially the gluing and finishing. I would however believe the stories about toxicity because it's in your best interest to not take any chances. Wear a dust mask, wash up after working with it, keep the shop clean ,etc. It's a great wood.

Answer 2: I do generally use Smith's All Wood epoxy on joining the back and with the blocks. I have done a few with Titebond and wouldn't hesitate to use it again. Cocobolo works well for bridges, fingerboards, peghead plates. although it seems to be heavier than Ebony.

Answer 3: I made a classical guitar of it with a cedar top a couple years ago. It is a nice sounding instrument -- maybe a little bright. It is greasy so wipe it down with lacquer thinner a few minutes before you glue it. I used Titebond with no ill effects but I know some people prefer epoxy. You may want to consider gluing the back strip between the plates instead of routing one in (that's how I do it anyway). The only concession I made to its weight was to make it a little thinner than I would Indian Rosewood. I have used it a lot as fingerboards on electric guitars. I haven't had any problems with the dust but it is, by many accounts, toxic. Use a good mask. Cocobolo scrapes pretty well which cuts down on the dust too. That's a good thing because it can really gum up sandpaper.

Answer 4: Try spraying a vinyl sealer on the wood to lock the wood down from the rest of the finish. This assumes you are going to do a nitro lacquer finish, but check -- I believe that the vinyl sealer is OK under varnish too.

Question: How can you make a "Rolling Pin" sander?

Answer: Take an old rolling pin and epoxy a steel rod into the existing hole in the center. Cut off one end just long enough to chuck into your electric drill. Take the other end of the rod and connect it to a handle with a bearing in the center. Make sure the handle is smaller than the rolling pin, so you can slide the sleeves on. Alternatively, take a long strip of sandpaper, wind it in a spiral around the rolling pin and tape it down at both ends with fiberglass packing tape. I buy my sleeves from Sand-Rite.

Question: Is there a good source for Koa?

Answer: Try Hawaiian Hardwoods Direct ( The sender had nothing but good things to say about them and the owner, Steve Schaeffer.

Question: How about guitar building woods in general?

Answer: Try Exotic Woods at or dial 1-800-GIDWANI.

 Question: Spraying a two color finish without bindings.

I'm spraying the finish on a Warmoth Thinline Tele that has a Maple/Swamp Ash body--no bindings. The radius around the edges is not squared off so a natural wood binding (PRS-type) is not very workable. I've already finished the back and sides in Dakota Red from Guitar ReRanch and will be starting on the maple top which I'm going to do in amber. I'm worried that when I spray the maple top that I'll get some "bleeding" where the different colors/woods meet. I don't want the red to "sag" when I hit it with the clear coats. Could I use something like a vinyl sealer to better "lock in " the color at the point where the different colors/woods meet?

Answer: What you do is seal off the red with several coats of clear, that helps prevent the bleed through. Then when you spray the top, you mask off the red and when finished with the top you do clear over it all. Red bleeds through I've found, so the clear will seal it pretty well. The vinyl sealer is really only for a seal between wood and the next coat, it fills in pores and allows a smooth surface.

It isn't the red that needs protected, it's the other surrounding colors. The red has a tendency to bleed or float into nearby colors or clear, that's why a good masking job is important here. Later on, you cover the amber with clear and then the whole thing again with clear to seal it all.

Question: What is the best grit for Crowning Files?

Answer:  It kind of depends what you want it for. If you have put a new set of frets in and only kissed the crowns to level them then the 300-grit should be all you need. But if I have just leveled a set of very worn frets that were almost flat even before I started, then the 300 is not nearly aggressive enough for me. I start with the 150, and it's still hard work. The 150-grit is rough, though, and I follow up with the 300 to take out the scratches. (Followed up by 400 paper, 600 paper, steel wool and the buffer.) I must say that the StewMac diamond fret files are the only fret files I have ever had that I used more than once or twice. I never found a toothed fret file that worked for me.  I used a safe-edged triangle file for years, until I got the diamond files about five years ago. I wish StewMac would make diamond-coated burrs for the Gurian file -it's a beautifully designed tool (the angled shank is just great for the body frets) and sits in the hand really well, but I don't like the burrs much - unless, as I said, I really want to hog off a lot of metal. I find it much easier to "clean up after" the 150-grit diamond file.

Question: What is a cold solder joint?

Answer: A slightly dull looking solder joint is nothing to worry about. A "cold" solder joint is often dull gray looking but not always. If in doubt about your connections you use an ohm meter to check them. Really bad joints often appear chunky or porous. Ensure you are heating both parts to be connected until they freely wick up the solder.

Sanding it is about the best way to get a good connection on pots. Soldering the ground to the pot can be very frustrating -- try filing or sanding a small patch to solder to.

NOTE: This is semi-controversial. A number of repairmen state that sanding will lead to corrosion on the pot, and a regular eraser is better for the job.

Question: Gelatin as a Hide Glue Substitute.

Has anyone used gelatin for hide glue on a repair? I have read where it does a good job. I am experimenting with some my wife found while cleaning cupboards and it seems to be a little soft when cooled. Will it dry out like regular hide glue? I want to glue a top back on with it.

Answer: Check out  (Frank Ford's site) go to the "big index page" click on "items for luthiers" scroll down to "Quickies" and a little article "hide glue from the supermarket" is there. It's the same stuff just clear, more refined, and a lot more expensive.

Answer 2: Yes, it works -- some suggest adding an aspirin to keep it from getting moldy. I get hide glue for between $4.50 and $6.00 per pound and a pound lasts a long-long time. The little packets of gelatin from the supermarket are about $22.00 a pound!!!

Question: Where are there archives of newsgroups?

Answer : has archives of all newsgroups.


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