I know that they make all these fancy framing clamps. But I don't have money to spend on stuff like that. So awhile back when I made my entertainment center I needed a way to keep the doors square while the glue set up and this is what I came up with. Ir worked for those doors and it works great for picture frames of just about any size I need to make. It seems that storing it would be a PIA but it actually stores very nicely out of the way. It is made from that press wood, so it doesn't warp, it is held together by a couple of peices of scrap plywood. You will notice that I have like a million brads in it, that was because I was joking with my brother-in-law about how Norm seems to put a million brads in his projects Using it is simple put the frame peices in, glue them up making sure they are up against the larger of my "L's" then place the small "L" against the oppisite corner and clamp with very light pressure if needed. In most cases the "L" peices will hold the frame in place nicely and I don't even need the clamps.