This problem is due to shrinkage of the back, not string tension. Loosening the strings may make the owner feel better, but it is not likely to have any meaningful effect (positive or negative).
Type: Posts; User: John Arnold
This problem is due to shrinkage of the back, not string tension. Loosening the strings may make the owner feel better, but it is not likely to have any meaningful effect (positive or negative).
The grading stamp has 'SPF' (spruce-pine-fir), which groups western species of similar strength. The spruce is Engelmann, the pine is lodgepole or other similar western pines, and the fir is white...
White oak is not as dense as most rosewoods. That perception of oak as overly heavy comes from furniture. It is only marginally denser than sugar maple (47 versus 44 pounds per cubic foot). When I...
Actually, celluloid shrinks more than Boltaron. The problem became much worse when Martin switched to a more environmentally friendly glue around 2003. It was not strong enough to resist the...
The MSDS for Duco Plastic & Model Cement (blue tube) lists ethyl acetate, no acetone.
https://ehslegacy.unr.edu/msdsfiles/36123.pdf
200 degrees F. is the magic temperature for reshaping celluloid safely. I have heard of the hot sand method since my early days, but I have primarily used a heat gun or boiling water.
The smell...
It is in the same genus (Diospyros). Persimmon lumber is mostly composed of pale sapwood, but occasionally has some black that is essentially "American ebony".
With the caveat that there are a wide range of properties within each species, these are my observations of average samples:
Low density and high stiffness are good.
Density, low to high:...
This is my most recent spruce patch repair, on a 1945 D-28 with a long history in Folk/Bluegrass. The hole through the top was 1/4" bigger than the bridge, all the way around. Previous repair from...
I have used both the Mohawk classic instrument lacquer and their piano lacquer. The latter has a higher solids content but less plasticizer. That makes it more susceptible to cold checking. I do like...
That is the original Indian rosewood bridgeplate, which is 3 1/4" wide. Those began in 1969 on dreadnoughts. Indian rosewood turns out to be a poor choice for bridgeplates. Chips and cracks between...
For strings of the same diameter (or core diameter), higher tension requires less compensation. Tension change from fretting, which is the reason for different amounts of compensation, is the same...
I used Indian ebony a lot when I started building 40+ years ago. IMHO, it is at least as good as African ebony. BTW, it is a true ebony (Diospyros spp.).
Sharp inside corner = stress riser. I have not seen a saddle break anywhere else. When I make saddles for archtop instruments, I always radius the corner.
I have had some red spruce guitar tops torrefied, but I doubt that I will use them. Lighter and stiffer (good), but more brittle and harder to glue and finish (bad). I had not considered this:
The proper term is pitch pocket. Pitch pockets can show up without warning during carving. The few times I have been made aware, I have replaced those tops for no charge. True knots in softwoods...
Grain count in diffuse porous hardwoods like maple does not seem to correlate with density, hardness, or stiffness.
The backstrap repair has worked every time for me.........even after multiple previous failed attempts.
Almost ten (October 2008).
This happened on what I considered my most important commission....a 12-fret dreadnought in style 42 for Norman Blake. It was an Engelmann top, and we had discussed every detail, including toner on...
I think what you are seeing is natural in the wood. Some Indian RW is particularly susceptible to this.
I met Elmo many years ago at a luthier's convention. We talked about cutting red spruce. Sorry to hear he is deceased.
The neck bolt should not loosen over time, but wood does shrink. A wave...
IMHO:
Mammoth ivory is not better than bone or elephant ivory. Some of it is very soft, and smells rotten. I would characterize the tone as a bit more mellow than bone, and not as loud. Pearl is...
Real mammoth ivory is available from reputable sellers, and is easily identifiable. You are correct in that it is not fossilized, but it is mineralized.
It is from extinct animals and is thousands...
If you damage the brass inserts, I have extras I can send you. The slotted adjustment screws are not so easy to find, so be careful with those. I echo the recommendation of using penetrating oil to...