Does it happen when cutting a board in half or when just trimming a bit off. I use a very thick blade with 96 teeth to prevent this from happening. I'm thinking it's a thin blade and it deflects when it hits differences in the grain of the wood. Kind of like a screw that wants to go in and follow the grain.

 

It happens during both, unfortunately. It drove me crazy because I tried going really, really slowly through the board and pulling straight down, and it came out worse than when I went quickly. I am using a thin kerf blade, though, a Freud Diablo 60 tooth. I wonder if it would be worth finding a full kerf blade.

 

That might explain some of the issues I've had when cutting on my 10" CMS. Do try a full-kerf blade and tell us and show us the results.

 

Are you clamping the piece(s) when you cut? do you have a non-slip surface on the mitre saw fence (180 or better sandpaper)
If the results are worse when you cut slow, then I would suspect that the piece is slipping while you cut.
Also, are you using a tall auxiliary fence?

It happens during both, unfortunately. It drove me crazy because I tried going really, really slowly through the board and pulling straight down, and it came out worse than when I went quickly. I am using a thin kerf blade, though, a Freud Diablo 60 tooth. I wonder if it would be worth finding a full kerf blade.

- jay443

 

Are you pressing the stock (too) hard against the blade? Test: set the miter and clamp the piece in place and cut 'no hands'. if problem stays, tool is broke/bent. If the cut is correct then always clamp.

M

 

I think Madmark has it. Start the cut s l o w l y. Be sure the material is firmly clamped or otherwise fixed so No movement occurs. I don't think you mentioned the blade you are using but a quality full left blade will certainly help.

 

Check the fence to see if it's vertically squared to the table. The DeWalt come with a high sliding fence. They're never square. I added some strips of painter's tape. Helps some.

Why cut vertically rather than flat?

 

Wichman has a point. If it's happening only on miters, the angle of the blade wants to slide the board in the direction the blade is facing.

 

Here's an idea to try: Keep the blade at 0, tilt the blade to 45, lay the piece flat and then cut. Check the results.

 

Thanks everybody for the replies! I will try out all of your suggestions. But I can say that currently I wasn't clamping the piece because I felt like I had a good grip on it. I will try these things tonight:
- check the fence for perpendicular
- clamp the piece and cut at a 45 deg miter
- lay the piece flat and cut a 45 deg bevel to create the same miter

 

Try my suggestion first. It may save you some frustration. I don't know much but I'm usually right. I just cut a miter with a 1×6 standing vertically against the fence and this is what happened.

When I put a square against the fence, it shows that it is tilted back almost a 1/16. Hard to tell by the picture but it shows you how and where to set your square.

No need for a clamp, no need to cut slowly, just hold and cut like you would normally do.