I know how not to make picture frames...

[Alan in Little Washington]

I have the same issues with 45° cuts, but one thing I can do is add the little degree symbol to my text

(hint use alt code: ALT248 = ° )

But seriously, the Dosch Universal/Lion Universal #4/ Pootatuck, etc. trimmers can do the job. But, first they are not designed to cut through the molding or framing stock. You must first cut a miter with another device, then use the "trimmer" to shave off a very thin slice to make it perfect. The trimmer fences must be properly aligned and locked, the blades razor sharp, and the stock must be held still.

 

[tvrgeek]

I have the same issues with 45° cuts, but one thing I can do is add the little degree symbol to my text

(hint use alt code: ALT248 = ° )

But seriously, the Dosch Universal/Lion Universal #4/ Pootatuck, etc. trimmers can do the job. But, first they are not designed to cut through the molding or framing stock. You must first cut a miter with another device, then use the "trimmer" to shave off a very thin slice to make it perfect. The trimmer fences must be properly aligned and locked, the blades razor sharp, and the stock must be held still.

That still leaves the question if there is more play in my Grizzly clone than a real Lyon. It is not much, but might be just enough to not be perfect.
If doing that last half a hair, it will deflect the blade. Full paper thickness, no problem.

 

[JGregJ]

I never mastered the technique, but worked ok the only time I tried it, The method uses a jig made from wood in the sled shaped similar to a baseball home plate that forms a 90 corner at the apex so you can cut both parts at the same time - that insures they are complementary. First rough cut the angles and leave it a little long, Then use the jig to cut both parts of the corner to get them to match. The hard part was shaving just enough off to get the right length, so I made multiple passes measuring each time and snuck up on the final length. Will not claim this is best way, but it did insure perfect 90 corners.

 

[gator]

I never mastered the technique, but worked ok the only time I tried it, The method uses a jig made from wood in the sled shaped similar to a baseball home plate that forms a 90 corner at the apex so you can cut both parts at the same time - that insures they are complementary. First rough cut the angles and leave it a little long, Then use the jig to cut both parts of the corner to get them to match. The hard part was shaving just enough off to get the right length, so I made multiple passes measuring each time and snuck up on the final length. Will not claim this is best way, but it did insure perfect 90 corners.

Sounds like the one I was trying to describe in my post above, except your description is much clearer and understandable.

 

[Alan in Little Washington]

To get perfect corner joints in a picture frame or any enclosed 4-sided item, there is one issue, just briefly mentioned by tvrgeek, that is just as important, or arguably more so, than perfect miters. In addition to cutting perfect 45° miters or, as mentioned, a perfect pair of complementary angles ( X + Y = 90°) at each corner, the lengths of opposing sides MUST be the same length, not just close, but precisely the same length to a degree of accuracy like the miters. If they are not the same length, perfect 45° miters will not help.

Also, though the corner joints may fit tight, the corners won't look right if the width of the stock is different from side to side- not typically a problem with manufactured frame stock.