Birch (Baltic Birch) Plywood – B/BB grade (aka Russian Birch) - 1/32" to 3/4" thick
Baltic Birch – B/BB grade (aka Russian Birch)
Baltic birch wood for laser cutting is sometimes called Russian birch or European plywood (one of the trade names is Europly). It’s typically from northern Europe and uses hardwood veneers for the faces and the core. The most distinctive feature of Baltic birch is that the edges are attractive, uniform stripes of hardwood veneer, usually alternating light and dark bands. That edge is largely free of voids. So, you can typically just sand the edge and allow the edge to be seen. You’ll see a lot of Baltic birch used in European furniture, cabinets, and store fixtures. Odds are that any nice cabinet drawers (e.g., in custom kitchens) are made from Baltic birch – take a look around and you’ll notice it in lots of applications.
Laser CuttingLaser cutting Baltic birch works beautifully, with most lab cutters cutting thicknesses up to 6mm and many cutting up to 12mm or more. The laser does leave a dark charred edge. You can leave it as is, or if you prefer, you can easily sand the edges to remove the charring. Remarkably, Baltic birch is quite affordable, and a lot less expensive than so-called furniture-grade hardwood plywood, which you might be able to find at the lumberyard. Baltic birch is definitely our go-to material for most wood applications. If we had to choose just one wood for the laser it would be Baltic birch.
Specifications and DimensionsBaltic birch usually comes in metric thicknesses: 3mm (about 0.120in), 6mm (about 0.24in), 9mm (about 0.36in) and so forth. Since each 3mm increment is about 1/8 of an inch, these thicknesses are pretty close to 1/8, 1/4, and 3/8 inch. The outer veneers are typically 0.75mm thick and the inner veneers are typically 1.5mm thick. So, a 6mm (1/4in) thickness is usually 5 plies, with each incremental 3mm of thickness adding or subtracting 2 inner plies. Of course, MakerStock provides pre-cut Baltic birch panels in the right sizes for the laser cutter, or to a size convenient for your project. All MakerStock panel dimensions are cut to tolerances of +0in/-0.188in. That is, the panel will always be up to 3/16in undersized so that it will definitely fit a machine with the corresponding nominal bed size.
Like all plywood, the faces are graded for quality. Our Baltic birch is B/BB, which means the better side is grade B and the worse side is BB. The B side is beautiful, with no knots or patches. Honestly, it’s hard to imagine what A is (and A is not readily available). The BB side is also very nice, but will usually have a few pin knots, only 2-3mm across, and perhaps a “football” patch. Typically you design your object such that the BB face is on the backside or inside of an assembled object.
You can finish Baltic birch like any hardwood. We like the wipe-on Minwax polyurethane. Sand first, and then apply thin coats, with light sanding between applications.
Baltic birch is a bit denser than softwood plywoods with a hardwood veneer. Density runs about 680 kg/m3 or 0.025 lb/in3.