Apply Venner to Top and Bottom?

Apply Venner to Top and Bottom?

I am getting ready to do my first veneering project and am feeling very confident. I have recently read quite a bit about it, and so far have decided to use hide glue and a J-roller to press it. But I also read that it is necessary to apply veneer to both sides to balance it out. The substrate is 3/4″ oak plywood, and it will be veneered with 1/32″ quarter-sawn red oak. Will it really be necessary to veneer the other side? And how about my choice and method of adhesive?

Michael Dresdner: Though I have to admit some curiosity as to why you are veneering oak plywood with oak veneer instead of buying quartered veneer plywood, your methods are certainly fine. Yes, you should balance the board by veneering both sides, even with a plywood core. Hot hide glue works well for veneering. In fact, if you miss a spot and find an air bubble in the veneer, with hide glue you can usually press it back down with a hot iron. You’ll also find that heating the wood and working in a warmed area will give you a bit more working time, and unless the pieces are very small, you will need all the time you can get. I presume you will be practicing this technique on scrap first, right?

For very large surfaces, it is much easier to veneer with either resorcinol or UF adhesive, as either will give you much more working time. However, they should be pressed and don’t lend themselves to roller or hammer veneering techniques.

Ellis Walentine: Absolutely, you need to veneer both sides. The cardinal rule of veneering is to balance the construction–in other words, have the same configuration of substrate and veneer on both sides of the centerline of the substrate. It’s not as important to use the same veneer on the back as the front, and many people use cheap, straight-grained mahogany or even “backer,” which is a pressed phenolic-impregnated craft paper, as their backing veneer. Either way, don’t shortcut this step. You might get away with it, but conventional wisdom says you’re rolling the dice.

Regarding hide glue and J-rollers…you didn’t mention whether you planned to use hot hide glue or liquid hide glue. Liquid hide glue will not work for contact veneering, because it doesn’t harden quickly enough. Hot hide glue does, and this is the basis of the time-honored practice of “hammer veneering,” which traditionally involves the use of a veneer “hammer,” a relatively heavy hammer with a very smooth, wide head that is used to squeegee the veneer down. I’ve not heard of using Formica J-rollers for this, but I see no reason it wouldn’t work.

My advice, though, is to practice your hammer veneering technique. It’s a sloppy and inexact process. My advice would be to consider making up a simple press with some waxed flakeboard cauls and hardwood beams and clamps. Or, if you have the resources, get yourself a vacuum veneer press.

Lee Grindinger: Balance is important. As moisture enters and leaves wood, even veneers, the size of the wood changes. If a panel is not balanced these changes in moisture can cause a panel to bow as a veneer expands or contracts in an unbalanced panel. If your panel is large or unsupported it is vital that you balance the panel with a similar veneer on the underside.

I think hide glue is an excellent choice. Practice your technique on scraps. Have a tool similar to a veneer hammer handy, warm water and a hot iron. Rollers work well once you have the glue evened out under the veneer but a J-roller is a bit soft for the initial stages. A more rigid tool is required to squeegee-gee out puddles of glue, bumps in the glue, or uneven swelling in the veneer or the substrate. I use a piece of Plexiglas with a rounded leading edge for this process and follow up with a wooden roller. A J-roller might have a bit too much give to it to really flatten the veneer and with only a thirty-second to work with you’ll need it very flat.

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