Thread: Flattening Veneers

The plastic tubing arrived and I bought a Wagner steamer. Two 200 mm wide veneers were steamed and then slipped into the vacuum press and left overnight. They came out looking like propellors. The sharpish kinks were gone, but the propellor shape was awful.

Took a couple of days off at the Gold Coast with SWMBO.

Today I heated those veneers again ... for 45 minutes this time ... just to make very sure the wood was close to 100 degrees all the way through. The veneers were left in the plastic tubing, laid out on the edge of a workbench and the veneers were clamped between an inch of bench top and a two inch lump of NG Rosewood. Because the veneers were left in the tubing and because clamping was faster this time I am confident that less heat was lost during clamping. In addition, the rate of cooling will be much slower this time.

I'll find out how things went in the morning. However, one thing is certain. I can never recommend that we cut green veneers to speed up the drying process. I have some cedar veneers (cut from dry timber) that are a couple of years old that are still as flat as the day they were cut and sanded.

This is a failed experiment, and I hope others can learn from it.

The veneers were taken out of the clamps this morning.

They still have a little of the propellor shape about them, but now it is minor and I think I can live with it.

However, yesterday's conclusion is as valid as ever. It is a mistake to cut green veneers.

Originally Posted by John Samuel

The veneers were taken out of the clamps this morning.

They still have a little of the propellor shape about them, but now it is minor and I think I can live with it.

However, yesterday's conclusion is as valid as ever. It is a mistake to cut green veneers.

Even commercial sheets of ply often exhibit the "propeller shape."

Not so sure that it is a mistake cutting green veneers, perhaps more like it being a mistake cutting green veneers from some figured woods.

I quite often cut green veneers, well more like thin boards / strips from woods that are no where near their final EMC. Yes, there are some regrets but overall it considerably speeds up the drying time. I tend to cut the more problematic woods prone to splitting & shakes down to manageable sizes for my applications. I'm also cutting for lamination work so not really concerned about surface defects.

Stacking green cut thin woods between sacrificial cauls and letting the thin strips / veneers dry by migration of moisture rather than air circulation & evaporation also helps. I use this technique quite a lot when glueing up laminations of thin strips & veneers for re-cutting into components for inlay banding construction. It takes longer to dry but is more reliable in producing "flat" laminations. It's very difficult to make accurate and precise components from cupped laminated boards.

Originally Posted by Mobyturns

Stacking green cut thin woods between sacrificial cauls and letting the thin strips / veneers dry by migration of moisture rather than air circulation & evaporation also helps. I use this technique quite a lot when glueing up laminations of thin strips & veneers for re-cutting into components for inlay banding construction. It takes longer to dry but is more reliable in producing "flat" laminations. It's very difficult to make accurate and precise components from cupped laminated boards.

Interesting ...

Had not considered this.

Nevertheless, unless I am desperate I think my days of cutting green veneers are over. Usually, I can buy most timbers dry, but on this occasion I had scored a bargain with green timber the seller needed to get rid of. Next time I'll bite the bullet, pay the extra and buy dry timber.