SMT cutting concave

[ejs1097]

I haven't used my SMT much.

This weekend I started a bookcase project and with a 12- 13" shelf/side width I decided to use it to cut to length.

I noticed it's making a concave cut when I run the pieces through with the SMT. The cut is dead on at the front and back edge but in the middle it's about 1/16th to 1/32 shorter producing a concave cut.

I don't have sandpaper on the SMT fence but every single cut is produced exactly the same. To me it seems like a travel probelm once the SMT gets in between the rails.

For this project, I don't think anyone will notice on the finished product and I'm using pocket screws for joinery so I'm hoping the middle screw will pull the sides in.

Anyone expereince this or know how to correct it?

[jackellis]

I had a lot of trouble making perfect right angles when using the SMT. Like an idiot, I kept checked only the alignment between SMT fence and blade without checking to see that the SMT runs parallel to the blade as well. Once I fixed that, crosscuts were perfect.

You might want to check for SMT fence alignment at several points, then recheck the table. If you unfasten the table runner assembly from the saw rails and then refasten them, I've found you must recheck alignment.