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Hi,

I've got pieces of old mahogany that are about the right size for neck and heel blocks - but they're not quartersawn, and the grain orientation is not at all alike the one I have from LMII - (where the dovetail looks like it's perpendicular to the grain) how much stress is on these blocks (OOO sized acoustic) and is the grain orientation important?

Plan b is to laminate three together with some hide glue and cut them lengthwise to have the grain oriented properly.

Yeah - I know - crazy to get so kooky about a $13 part, but hey, $13 is $13.

Thanks!

Interesting...

I used Flat Sawn wood for my Bolt On neck. I didn't want to chance the bolts splitting the neck block on the thin section.
Probably not an issue -- as it is massively heavy otherwise....

I did laminate this neck block out of 2 pieces of flat sawn stock -- but it was still flat sawn afterward.

There is a pic of it in my Ditson Bracing critique post.

Thanks

John

Your grain orientation is important in that you don't want to be gluing the top and back to endgrain in the neckblock. So your grain should run side to side, not up and down. Of course, others may feel differently, but as a rule, you want to avoid gluing to endgrain, 'cause it has a higher failure rate. IMO...
dave

I see two reasons to make sure that the grain of the heel block runs parallel to the sides.
[list=][*]You are not gluing cross grain to the sides.[*]You are not gluing end grain to the top and back.[/list]

I know of some builders who make both their heel block and tail block out of plywood so Neither of these reasons are particular compelling and you probably won't have a problem.

That is also my understanding of the issue. I think it is more important than gluing top or back to endgrain.

_________________
Alain Moisan
Former full time builder of Acoustics, Classicals and Flamencos.
(Now building just for fun!)

My understanding about putting the end grain on the sides rather than top and bottom of the blocks is to make machining easier, not so much about glue joints. This way, the end grain sides of the blocks are just kinda living out there in nowhere land without any glue joints on them, so if they aren't absolutely perfectly square or flush or whatever, no biggie.

Gotta say, getting an end grain ends on a piece of wood squared up nicely is more of a challenge than getting a not-end grain section squared up.... Sanding also seems quite a bit slower on end grain vs long grain. Chipout is also more of a problem on end grain.

Then again, I will say use what you have available. If you laminate them, just take the time to joint the lamination faces properly so that you get good clean glue joints.

Good luck

John

Grain direction side to side. You will find, among the other good points mentioned here, that shaping and fitting end grain sucks.

Thanks!!

Great responses all - appreciate your help.