I'm trying to join two pieces of plywood side by side using a groove and spline for support. However, it seems like router bits only go about 1/2 inch deep, and I can't find any splines available for purchase, just trim pieces that are oriented with the grain along the joint seam. Should I consider using a thin metal rectangle as a spline instead?
3 Answers
You might want to look into sourcing specialty 8' x 8' plywood sheets instead. They might not be common, but they do exist. Just an idea if you're open to alternative materials!
If you're joining plywood side by side, I really recommend making your own splines and using Titebond III glue. Just be aware that any flex in the wood could lead to joint failure, as plywood isn't really designed to be joined like this.
Typically, people cut the slots for splines using a tablesaw or opt for making their own with something like 1/4" plywood. Just keep in mind that whatever you use probably won't be structural. You might be better off using a tongue and groove joint for added strength.