Finish to minimize movement

[Matt Benton]

I'm working on my first project and decided to go with plainsawn White Oak.

Is there a particular finish that would help minimize bowing? I assume I would want to keep out as much moisture as possible, but don't know much about finishes.

Thanks for the help!

[Joe Chritz]

Probably not unless you use something like a complete epoxy resin coating.

There are ways to stabilize wood so it won't move but it really isn't "wood" anymore after that. It is used for knife handles and isn't practical for a project of any size.

Finish all surfaces with you finish of choice and choose good wood and it should be fine. You really won't stop wood from some movement so build accordingly.

Joe

[Jeff Craven]

I've read that you should finish both sides of the wood equally, so that the moisture exchange is the same on both sides.

[John Schreiber]

Wood movement is a fact of life for anything made of wood. Wood structures of any type must be designed with that in mind.

[Jim Becker]

No finish will provide the properties you desire. Shellac will slow moisture passing, but not stop it. The best way to deal with wood movement is to build a project with wood movement in mind.

[Steve Schoene]

I'll pile on, too. Every article made of wood needs to be designed to accommodate seasonal wood movement. The key is that the movement is only in the width--length remains essentially unchanged. You can get a good idea of how much change to allow for by looking at www.shrinkulator.com which allows you to plug in various woods and widths. As a guide--wintertime wood may reach a low of 6% or 7% and in the summer in might reach 12%. In most climates these would be pretty much the extremes--most well air-conditioned houses might avoid the higher percentages.

A heavy shellac finish might narrow the swings by several percentage points, but not sufficiently to avoid considering the effects of movement in the design. (By the way, the reason Jim and I mention shellac is that it is about the best finish for any given thickness at blocking water vapor.) Allowing for the movement is easy, and so often done that designs that neglect that might well look odd anyway.