Any tips on getting splines just right?
To create the spline grooves accurately, use your router table and a few featherboards to hold everything tight against the fence -- just make sure you place a mark on the top or bottom face of all the pieces (your choice). Then make certain this mark consistently faces outward (or inward, again your choice) while you route all the grooves. This way if your grooves are not perfectly centered you will have created the same error all the way through the project and everything will still fit together perfectly.
For the spline, the easiest way to go is to use a plywood sized router bit and then cut them from a sheet of plywood that fits the resulting slot (experiment with scrap first). I have a 7/32" Freud bit (available from Home Depot, IIRC) that fits 1/4" plywood nicely. I've used it with the crappy 1/4" birch plywood available from Lowes -- it's not good plywood for much else, but it makes nice splines. Without glue the plywood might seem a little loose in the slot (but not too much so). Once a water based glue is added everything will swell a bit and the result will be a secure splined joint.
If you prefer a solid wood spline, remember that the spline's grain should run perpendicular (or at a significant angle, say 45deg or so) to the edge (e.g. endgrain should be visible along the spline's length when installed) for maximum strength. You can use a thickness planer to machine the splines to match your router bit, but you will have to create a series of shorter splines (my DW735 maxes out at 13" width) created from a long, thin, piece of wood. You would then use these 12-13" long splines to fill the length of the spline joint (there is no rule that says a spline has to be a single solid piece of wood running the entire length). Once thicknessed, cut them to their proper length and width at the table saw or bandsaw. Just beware that alignment of the edge banding may take a little longer with multiple short length splines, so you may wish to use a PVA glue with longer open time.
There are a multitude of ways to create the splines, so just think the process through using the equipment you have available to you. Once you are confident you have a safe process, go to work. If you do not have a router table and/or can not get hold of plywood sized bits, you can even use a dado blade on your table saw to create the spline slots, just beware that most dado sets have a minimum width of 1/4" or thereabouts, so plan your splines accordingly. Given the dimensions of the edge banding, *I* tend to feel safest grooving them on my router table -- YMMV.
PS - If you use a ratchet strap, be sure to protect the corners. The straps tend to apply the greatest pressure at each corner and that can result in crushed corners.
HTH
