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Been thinking of laying up some Baltic 11 ply 7/16" birch as nose blocks with a dovetail (mahogany) neck. Anyone done this? Does it work alright? Any disadvantages?

Haans,

Lots of builders use Baltic birch for blocks, especially tail blocks. I don't see any reason why a neck block laminated to the appropriate thickness from Baltic birch wouldn't work also. You'd never have to worry about splitting one, although as long as the grain orientation is correct, mahogany blocks work very well. I've seen only a couple of failures in 30+ years and they were the result of abuse and not wood failure.

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Jimmy Caldwell
http://www.caldwellguitars.com

Well Haans, to answer your questions

Yes
Yes
and
Non that me has experienced.

I find baltic ply to be exceptionaly stable.

By the way , me sure do likes your mandos. A1 work.`

blessings
the
Padma

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Audiences and dispensations on Thursdays ~ by appointment only.


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What is a nose block? Neck block maybe The tool push off on the ply is a bit higher than solid mahogany because of the varing grain directions of the individual laminations in the plywood. But you overcome that by lighter multiple cuts when mortising you dovetail mortise.

Also the plywood will dull chisels faster for the same reason combined with the resin

I've got 2 reasons I haven't tried baltic birch plywood for dovetail neck blocks.

1. Although the ply looks good, it doesn't look......normal when you look inside a guitar. I bevel the edges of my neck blocks and this would really bring out the......plywood look.

2. This reason may not be a cause for concern. It doesn't take much to hold a dovetail in, but 1/2 of the thin plys are end grain, and there's also the glue holding the plywood together. Is a dovetail mortise in plywood good enough to glue the neck to? Would the steam necessary to remove the neck, if it ever needs to be removed cause problems with the glue holding the plys together?

I use baltic birch plywood for the tail block, but I've always used Mahogany neck blocks.

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I didn't mean to say it, but I meant what I said.
http://www.brackettinstruments.com/

Ah, yes Michael, neck block as opposed to the endpin block...
Woody, your post may have answered my question. I was worried more about the joint and the endgrain of the ply. I've usually used mahogany to mahogany or maple to maple on mandolins, so maybe I'll laminate some mahogany in some creative way. I'm not really concerned about ply laminations look, eleven ply Baltic is a rather high quality product and It doesn't bother me much that it's visible if it does a specific job well. I've never subscribed to convention much on the inside anyway.
It did occur to me that the Baltic may not be steamproof...I may drill a hole in a chunk and steam 'er up to see what happens.
Paddy, thank me you (just a little Frank Wakefield talkward backing)! I will probably use Baltic on the endpin block.
Thanks all!

Hans, don't go there! You'll be cursed forever when the time comes for resetting the necks of your guitars. Steam and plywood don't go well together. At all.

Besides, baltic birch ply is too heavy for blocks; it just adds dead weight.

Zat you Mario?
Yea, probably not a good idea. Will stick with mahogany. I was a little concerned as I steamed a neck off yesterday and the mahogany looked pretty soggy. I guess Baltic birch would look like particle board after steaming...

Make your own out of Mahogany. Best of both. Wouldn't take long to glue up. Use a urea formaldehyde glue like Uni-bond for a stable rigid and water/steam proof block.
I haven't found Baltic to be very stable. Rip a strip on the table saw and watch it take off. Panels warp very readily even if straight when purchased. If it displays any tameness it is that it's stable by nature of the type of construction not by the type of wood. The alternating grain in plywood is a great way to make a stable panel or piece of material. Mahogany is a very stable wood. Combine the two and
Birch is a unruly wood plus they aren't using that high a grade of wood in plywood. Birch is strong but heavy. True in a small piece like a heel block you might not notice it but still....
Plus unless you have a immediate use for the baltic you have a lot of material for a little block. Plus (again) if you make your own you are not limited to a certain thickness. Plus (one more time) baltic is hard to shape, carve where as a home made mahogany ply block is easy.to shape.
Plus (last time) mahogany is lighter.
Link

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Cut to size.....Beat to fit.....Paint to match.

The only thing that i think is wrong with a plywood blocks is their weight compared to solid mahogany. They are heavier.

Edit: didn't read grumpys post where he mentions basically the same thing.

Well, flying in the face of convention again, I'm not that concerned with a few grams of weight as these are 12 strings and frankly, to be able to use .070-.014" strings...they are built relatively heavy with thick tops, large bridge plate and laminated braces.
I have (with all your help) talked myself out of it quickly. The "aircraft plywood" sounds interesting, but I see it comes in 1/4" max and that would take a lot of layup with epoxy; messy, and that would get heavy.
I guess it was just a fleeting thought on an overworked day...

Again, thanks for the input folks!

Don't know if it would relate to nose blocks, but didn't Gibson use plywood for bridge plates for awhile - and the problem was that they were too stable - thus causing tops to crack?
Walter

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Walter Lay
"It's taken me so long, but now that I know
I can see. All that I do or say, is all I ever will be"
- Billy Joe Shaver

Gibson used some kind of laminate for bridge plates on the guitars with adjustable bridges. I don't know it they used them in other models or not.

FWIW Gibson used Spruce for bridgeplates in LGO's. I've replaced several of them.

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I didn't mean to say it, but I meant what I said.
http://www.brackettinstruments.com/

I used a baltic birch bolt on fretboard extension on the guitar I'm currently working on. When I tightened down the bolts for the fretboard the first time, the birch delaminated right away (hardly any pressure applied). It didn't delaminate from the ebony fretboard but in the layers of the plywood. I just don't trust the glues and joints in commercial plywood anymore. The quality has come down in plywood in the past few years. The neck seems like a high stress area. I feel better about trusting my own joinery - for what it's worth.

.220"
That's thicker by quite a bit than my 12 strings! And get a load of that bridge plate!!
Well, in defense of Gilson, their mandolins weren't any better...

I wouldn't hesitate to use Plywood for a bolt-on neck block....
I have seen every sort of wood you can think of including Spruce used successfully for bolt on neck blocks.... (Well, I haven't seen Balsa used yet...)

I would be more careful with a Dovetail neck block -- as Mario said, Consider Neck Reset time
Steam + Heat + Plywood = Delamination.

Thanks

John

Martin uses plywood blocks in their bolted and glued mortise and tenon necks. There is definitely a problem with the bolts loosening and the glue joints failing. However you are planning to do a dovetail so the mechanical joint should provide the necessary strength to hold the neck in place.