I read a post suggesting that the lams should be heated before glue-up.  Unless there was moisture in the lams what would be the purpose of heating?

I pre-heat the lams, glass and riser- I think it helps with glue adhesion. If there is any additional moisture in your lams it takes care of that too.

Elmont suggests one hour of pre heating and like Trux said I preheat all components of the bow

Shawn

I do as well, I think it kind of opens the pores of the wood and allows the glue to penetrate a bit.

I've never heated them, and never had a failure.

I preheat the form also.

I've done it both ways, can't tell a difference. Never had a failure. I live in a very dry climate though.

I think the heating suggested by elmont was for the limb components prior to glue up and was for removal of moisture. By the time you get to the epoxy the lams ect.. have cooled back to room temp anyway. IMO
Terry

I think it certainly helps to get the epoxy soaked into the pores of the wood  when you are applying the epoxy, but if you have enough on there it will happen in the oven anyway.  I've tried it both and I cant tell a different.  And for the last 10 bows I made I did not preheat.

i heated my first few with no problem--THEN-i heated a set of lams and they wrinkled up like 3 year old ribbon candy!!!since -i have not heated and haven't had a problem---brush the lams real well and you'll get all the dust and fibers[loose] off--good to go
-------------mike

If the humidity is high I heat the lams with a hair dryer . I use thin enough lams that a few minutes removes any excess moisture. Most times I do not preheat. Thelams are cool when you apply the glue anyway so actually helping with adhesion is a mute point in my opinion. What you do not want is gas bubbles under the glass which look ugly and cause delaminations if to much. Always preheat if doing extremely dark laminations under clear glass. Walnut, Cocabola ect.