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Just baked some tops, heated to between 90/100 deg. C, left for an hour, switched off and left them to cool overnight in the ventilated (3/4" holes top and bottom) heat box before I take them out and stickering them in the morning.
So how long do you think I should leave leave them, in a controlled environment like my guitar workshop, before building with them?
Is 3 weeks good?

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The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.

3 weeks would be good I'm sure, probably less.

Weigh them accurately. When they stop taking on water after the dehydration process, they have reached equilibrium with your shop RH (controlled, one assumes) and are good to go.

Thanks Ed, I'll be doing that anyway, just wondered if there might be any other things that may come into play.
For example, I've heard it mentioned that baking tops not only removes most of the moisture, but crystallizes the resins.
And it must be quite shock to give a piece of wood a blast of heat like that!
Got to do the same to some brace-wood as well.

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The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.

The only real difference I've noticed is that cooked tops are preshrunk, so are less liable to crack in the future through RH swings.

Measuring density and stiffness etc, the changes are so minute as to be just as likely to measuring errors as changes to the wood.

The preshrunk is what I'm going for, got some of this past years adi harvest I want to build with soon which is starting to cool now
I did notice that the trial run with some lutz dried out/crystallized (?) a small pitch pocket outside the pattern rather nicely.
An hour at those sort of temperature won't have left much turpentine in it.

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The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.

I would bake at 200F for an hour with a slow cool down and then set the tops aside for two weeks before building with them.

Can't say that I have any data either about results since none of mine either pre-bake days or post-bake days has cracked.... yet.

I baked some wood and at the end used a spray bottle and sprayed some water on the inside of the oven. Instant steam and I let them sit like that for a while. I figure it gives the wood a head start at absorbing some moisture when at temperature.

Eeeeek!!
Sure guess it would, but I'm not in that much of a hurry.

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The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.

How else do you learn things?

I use 3 of these for baking tops then load in the oven at 200F for 2 hours. Brian Burns has done a lot of study on the baking subject and has found a significant increase in stiffness of baked tops. I find that the tops re-acclimate in 2 days time, and stop re-absorbing moisture in your climate controlled shop. I wish my oven worked in convection mode below 300F.

Bob

I microwave my tops.....

First I have to cut them into quarters though so that they fit on the turntable.....

I'm still waiting for someone to post that one of their clients is complaining that the guitar that they bought from you smells like bacon....

Actually. I know of someone who microwaves their tops in a commercial sized microwave....

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The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.

Thin wood takes just a few hours to acclimate -- so I agree with Burns

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Ken Cierp

http://www.kennethmichaelguitars.com/

So then, why not do them at 300F? Won't hurt them

Grant

True enuf, Grant.

Bob