Official Luthiers Forum!

The inside the box version- just to be clear. I've got some rift sawn mahogany that I'd like to use because it's half the weight of the Pau Ferro and a good bit less than the Dalbergia Cultrata I've been using. I've got plenty of scrap ebony as well. I know a lot of people like to use maple for it's hardness. Just wondering what some of you think about using other hardwoods. I'm building a bunch of fingerstyle guitars so I plan on using a couple different materials anyway just to see if I could tell the subtle difference. The thinking was obviously to get lighter and more responsive, but not at the expense of the instruments integrity.

o orange

I would not consider mahogany hard enough. Considering the importance of the long term durability of the plate, and the price and availability of maple, it's not worth the risk of long term problems IMO.

My recollection that one reason mahogany is a preferred furniture wood is that it is easy to carve. In the case of the bridge plate, that translates to "easy for the string beads to wear down."

That's what I was afraid of. I suppose I'll stick with the rosewood.

I've made them out of spruce with a AFB ball end plate, BRW, AFB, ladders from spruce with the AFB plate, BRW. Depends on the tonal qualities you are after.

I've been using black locust.

_________________
Steve Smith
"Music is what feelings sound like"

Personally I think maple is too active. I'll stick with rosewood...

I've contemplated doing what Haans has done - a small ball end plate on top of or inlet into the bridge plate.

Some of the old ladder braced guitars had a large spruce bridge plate without any additional reinforcement. Not great over the long run.

Wish that I could too, but I'm not going through the CITES drill over a bridge plate...

Usually there was enough rw scraps lying about to always have some material...

I'm often struck by how much damage is seen on maple bridge plates after just 10-15 years of service, but don't find the idea of a carbon fiber laminate appealing. With all the Dalbergias off the table as far as avoiding CITES paperwork, what other medium density, high side-hardness woods - in addition to osage orange and black locust - are builders using? It seems like dogwood and apple would both be similar in density and hardness to black locust, while American beech would be a bit less dense and of slightly lower hardness - essentially the same characteristics as hard maple. Persimmon seems to be both hard and of moderate density, but difficult to source. Other ideas?

_________________
For the times they are a changin'

- Bob Dylan

There are plenty of non-cites tropical hardwoods that would fit the bill for a tough wear resistant plate. A piece of what they are using for flooring these days would probably provide a life times worth of bridge plates for the average single man shop.

But maple works well for other reasons and if it isn't buried under the bracing is somewhat replaceable.

I've used padauk and thought it was pretty good.

I use persimmon. It has a cross linked grain structure and it won't split. It's hard enough that Al Carruth uses it for fretboards. I don't have a sense of its weight relative to maple or rosewood. I'd have to weigh some of it. I was given a chunk of it so I don't know where to get more when I run out.
A quick search on the net shows that getting some for bridge plates shouldn't be too difficult.

I don't understand. Lots of comments about the abilities of various woods to survive use/abrasion/various other insults. Would not a few grams' worth of aluminum or brass sheet make a lot of the worries irrelevant? Strip of .020 aluminum or brass with six holes in it and no more concerns about string ends pulling through, compressing, or otherwise insulting the bridge plate, no matter what it's made of.

_________________
Peter Havriluk

That's a thought that I might have tried back when I was building, but like metal bridge pins, might change the tone. I also thought of ironwood or hornbeam, but was satisfied with BRW or AFB. CITES isn't going to climb inside your guitar to check the bridgeplate. Probably why I never dated my instruments either...they were all built in 1915.

" Would not a few grams' worth of aluminum or brass sheet make a lot of the worries irrelevant? "

Go all in - carbon fibre and titanium!.... or not...

I happen two own two old Martins from the "over built" period of the 1970's. Both have had their necks reset by an individual who is noted for the somewhat controversial option of rescalloping braces and replacing the heavy rosewood bridgeplates with smaller maple ones. I had both done to my D18 and when it returned my wife's comment was "you are playing louder tonight" (I didn't think I was doing anything differently. The guitar was taken to a bluegrass jam and played along side a D18GE and a 1937 D-18 (yes, a real one). Everyone thought it held its own nicely.

I then sent the D12-28 off and had its bridge plate replaced and have been equally happy with it. (And I've used small maple plates on everything I've built as a result)

Persimmon is about 2,300 lb janka side hardness and 52 lb/cu ft, versus locust at 1,700 lb and 48 lb/cu ft, and hard maple at 1,450 lb and 44 lb/cu ft, so 1/3 again harder at about a 1/6 increase in density re: hard maple.

A maple bridge plate of traditional configuration weighs about 0.30 ounces, while a persimmon plate of the same dimensions will run about 0.05 ounces more. African blackwood would run about 0.54 ounces.

_________________
For the times they are a changin'

- Bob Dylan

I've never given tone a consideration when thinking about bridge plates but rather strength. I've almost always ever used cutoffs from the sides or back of what ever guitar I was building with the exception of mahogany and maybe walnut as that seemed too soft.

IMHO the choice of bridge plate for tonal purposes is in the realm of voodoo. Maybe one can actually design a guitar where the bridge plate is an important choice of wood for tonal purposes, though I have my doubts, but none the less it serves a well known engineering principal.

Mass, stiffness, and strength (as opposed to species) does make sense in that area though.That's why I have used some that are a thin hard plate like osage orange on to a spruce patch.

i'm making a tiny pro-bono copy a washburn rover out of leftovers for somebody so they can get back into playing. bp is bubinga from my rosette stash. i didn't have any eir with the grain where i usually like it and bubinga seems to have a q comparable to eir so we'll see.

" the choice of bridge plate for tonal purposes is in the realm of voodoo"

I don't entirely agree with this statement. Although I don't think the bridge plate is a "make or break" thing, I do think it's physical properties do have an effect on the sound of an instrument. Things within the proximity of the bridge seem to have a greater impact than those that are further away.

I agree with jfmckenna: the mass and stiffness of the plate probably have the most effect on the tone, while hardness and split resistance are what count most functionally. In terms of the latter, I've found few things that beat persimmon, although hornbeam is right up there. If you're in California, you might want to look for some soft-shell almond wood, which is pretty hard too. All of these are diffuse porous, like maple, so you won't run the risk of ball ends falling on a softer ring line, as you might with Osage, locust or ash. I keep the mass down some by tapering the plate's thickness in front of and behind the area that takes the string balls. I like to make the plate so that it extends out past the front and back edges of the bridge, and taper it to a feather edge there to avoid the stress riser and reduce unnecessary mass. If I felt the need for a harder reinforcement for the string balls I'd be prone to use a small plate of bone about a half mm thick.

Early Larson style GC-6 with spruce doubler plate and AFB ball end plate...



Nice thing about AFB is it is fiberous and dense. Sweet clear tone with deep bass.

Late Larson style with BRW plate...



Stronger, cleaner tone.

Bloodwood (brosimum rubescens); Gidgee (Acacia cambagei).

_________________
Trevor Gore, Luthier. Australian hand made acoustic guitars, classical guitars; custom guitar design and build; guitar design instruction.

http://www.goreguitars.com.au