How to align sliding miter saw

I purchased a one+ 7 1/4″ sliding mitre saw and read the manual.   I cannot figure out how to align so that the sliding direction (run out) is parallel to the blade surface and perpendicular to the fence.   All the manual tells you is how to align the blade surface so that it is perpendicular to the fence by moving the fence.  But my new mitre saw is slightly off so the sliding direction (run out) is not parallel to the face of the blade.  So aligning the face of the blade to be perpendicular to the fence does not produce a square cut if you are using the slide to do the cut.  I took the blade off, checked it was flat and reinstalled it, doesnt help. 

 

Any suggestions? 

 

Thanks!

Unfortunately I’ve seen this in most major brands of miter saws. You can square the blade in fixed position, but then the sliding action is off about 1/16”. I can get the sliding action to cut  square to the fence, but then the fixed cutting is off by the 1/16”. My research tells me the machining process is off somewhere. I believe the rails aren’t machined parallel to the blade. It’s very frustrating! Dewalt seems to be the only company that can get all the parts machined properly so the components are square and parallel. 

Hi, I found that the fence was not square, I put a trusted engineers square across the fence and found it to de out by nearly 3mm. So squaring from from the fence to the blade will always be out, I have had my fence milled levelled in the horizontal and vertical. Hopefully just another area to check.