Baked Tops

[Daniel P]

Can a top be baked after being joined, or is this best attempted with unjoined pieces?

[ken cierp]

Likely the glue is going to fail -- to me not a good idea. Notice in the info above its about controlling cracks from shrinkage, now you would be inviting a joint failure. And also notice that Bob Taylor takes a giant leap away from asserting these baked tops sound any better.

[John Link]

Ken,

Would that not depend upon the glue used for the joint and the temperature used for "baking"? That is, are there not some glues that could survive the treatment? (Titebond - not.)

The reference to "oxygen free atmosphere" used by Bourgeois Guitars for their "Aged Tone" finish process reminded me that all good sounding pre-war Martins have been stored in helium filled bags when not in use.

[ken cierp]

I would never plan to bake a joined top

I would not take the risk of the glue failure no matter what glue was used ---- where's the value add?

[John Link]

The "value add" concerns tops with pliage, not flat tops. Joining a pliaged top after each half has been bent is clearly possible (Michael Collins demonstrates it on his DVD) but the amount of pressure that can be applied to the joint appears to be compromised due to the compound curvature created by the finished bend. Michael uses only masking tape. In theory a jig could be made to hold each half in alignment for clamping, but it seems like a bear of a job. Much easier to clamp and glue first, bend later. Might be a place to use hide glue or a formulation of epoxy that was heat resistant (assuming there is such an epoxy).

The bending process itself seems like it would replicate Taylor's baking. Collins advocates using a light box, something (remotely) like the original Fox bender, and I suppose it would raise the temperature of the wood well above 200 degrees.

[mike-p]

'All good pre-war Martins stored in helium bags?!?'

Really? I've never heard of such a thing and i've never played a bad pre-war martin and i find that the not quite so good ones are usually in need of neck sets etc that would probably up the standard of their sound.

[TonyinNYC]

Ken,

Would that not depend upon the glue used for the joint and the temperature used for "baking"? That is, are there not some glues that could survive the treatment? (Titebond - not.)

First, Ken, thanks for posting that info from Bob Taylor. It clears up why he bakes his tops.

Second, I see no point in joining the top first no matter what kind of guitar you are making. Besides, you would need a rather large oven to fit a joined top in. Plus, the heat may cause the pliage to relax and also the glue to fail. Also, when baking, I think it wouild be a good idea to sticker the wood and clamp it in its stickers to keep it from warping. Although I may be wrong about that and its possible the wood wont warp at all.

Third, where in the world did you hear this:

all good sounding pre-war Martins have been stored in helium filled bags when not in use.

I have never heard that before and I frequently lurk at the UMGF. If helium made guitars sound better, or the lack of oxygen in their storage area, people would be talking about it non stop over there!