87, страница 10

choosing

Plywood for

the Shop

Learn about plywood options that are great for projects around the shop.

Domestic birch may not be the best choice for shop projects. For durability and strength, I turn to Baltic birch plywood.

Baltic Birch. When you say "Baltic birch/' most people think of a plywood with many thin plies like you see in the photo above. These layers are assembled with alternating grain directions, like conventional plywood, using interior-grade glue. The difference is that all of the plies are made from birch (photo below).

This type of construction makes a strong and stable sheet of plywood. It's a much stronger material than domestic birch plywood. The inner plies are void-free and it does a great job of holding screws. Thaf s why I like to use Baltic birch for projects like the hobby chest on page 26 and for jigs like you see in the top left photo on the next page.

Another great benefit of using Baltic birch is that it's available in a wide variety of thicknesses (top right photo, opposite page). But there's something you should know about thickness. Plywood imported from other countries is measured in millimeters. You'll have to take this into consideration when you purchase your plywood.

A close cousin to birch plywood I'll sometimes use is Finnish birch-

90 ShoDNotes No. 87

Cabinet Grade. If you look at the photo below, you'll see a sample of cabinet-grade (or "domestic") birch plywood. It's widely available at most lumber yards and home centers.

Look closely and you'll see a very thin outer veneer of birch on the faces. But what's on the inside? The core of cabinet-grade birch plywood is actually made of fir, like most construction-grade plywood.

There are a couple of problems with using domestic birch plywood in the shop. First, it has relatively few plies. And since fir is a softwood, it's not as strong and doesn't hold screws as well as some other types of birch plywood. I've also found those inner plies can have a few voids.

< Cabinet-Grade Birch Plywood. The oniy birch used in this product is on the front and back face veneer. These outer veneers are very thin and the core plies may have some voids.

Over the years, I've used a lot of plywood for jigs, fixtures, and other shop projects. You already know there are many types of plywood to choose from. But how do you know which ones are best for use around the shop? To find out, let's take a look at a few different ones you might want to consider.

BIRCH PLYWOOD

One type of plywood I use a lot of is birch. But what can be confusing is that all birch plywoods are not the same. So what's the difference?

Arauco Plywood. Imported from South America, the inner plies and faces of this product are made from radiata pine cut from managed forests.

Baltic or Finnish Birch. Known for its many thin plies, this plywood is dense, straight, stable, and easy to work with. It's imported from the northern Baltic region of Europe.