Hi BW - gotta laugh - been there many times and it's humiliating to say the least - I feel your pain. Seems so simple which is I guess why it's so hard! It's exacting.
Sounds like you're using a miter saw, which is what I have to do as well, having no table saw.
Couple of thoughts should you attempt to try again - easy way to check and adjust your miter saw fence for 90 (nothin works if you're not there to begin with) is to cut a piece of wide stock (as wide as your saw allows) at 90 - leave one side there on the plate and take the other side and flip it over and try to butt them up again - is it good? if not, adjust the fence itself and do it again till it's perfect.
For cutting equal length sides, cutting to a mark doesn't "Cut it" for me - use stops clamped to the fence to get them all exactly the same - most likely whether the overall frame is off by 1/16 or 1/8 doesn't matter, but having any one side off by that amount will kill ya! If the stops would have to be beyond the end of your fence, clamp an extension onto the back and then a stop to the extension.
If you're tilting the blade for your cuts to 45 because your stock is too wide to cut verticaly - do NOT rely on the scale - use a good 45 degree triangle to set it and make sure you're not hitting the teeth - make sure the triangle is only on the flat part of the blade.
For clamping, I really like the straps with the adjustable 90 degree corner cleats - I don't use the regular screw down corner clamps anymore. There's also plenty of framing jig plans out there as well, but the straps work well for me. With the right tension, they'll pull together any slight imperfections.
If you're like me they'll be close but never quite perfect - once they're glued up try running a rounded burnisher (like the shank of a screw driver) along the corner - it'll fold the edges right up ... and I won't tell if you don't!
Probably told you things you already know, but I've been able to make them pretty well with the miter saw if I'm careful and follow those routines.
Of course, like you said, there's always the framing store but that's not near as much fun now is it?! ...... ;-)
Last edited by Gilbear; 04-24-2006 at 08:53 AM.