3d cut problem ?

[bob_s]

I posted this question on the Aspire board, and they think it's some play in my shopbot? The rest of my cuts seem to be fine, although I don't know that I would notice a few thousands on a cabinet or box part.

45752.jpg

45753.jpg
Any suggestions would be appreciated.
I am cutting out some large sculpted letters from 1 inch MDF.
3/8 Centurion ballnose
offset with 9% stepover
climb cut
3.5ips 14000rpm
The sheet is screwed down arond the letters so there is no chance it is moving.

The quality and speed are fine, the problems are where the program decides to leave one area, jump to another and then come back later. If it would just start on the outside and cut inwards I would have only a tiny bit of sanding. However the folks at Aspire said that it is not controllable.
I haven't tried cutting it with a raster pattern, I know that will start on one side and progress all the way over with no interruption.
I find it strange that the error occurs all the way around a part, if it is the machine? It is not plus on one side of an object and minus on the other, it all seems to be a little too deep after it comes back to match up with the previously cut area. It does not show in the preview, but it is only a small height change & I don't know how much detail really shows in the Aspire preview.
I think Gary Campbell (or someone else?) posted a big article on how to adjust the Z carriage a few months ago, I cannot find it, if someone could post the location I would appreciate it in case that is where the problem is.
thanks
Bob

[beacon14]

Does it seem to be more pronounced the farther away from the screws you get? Even with multiple screws the material can flex and lift slightly between the screws as wood is removed.

[joewino]

Have you considered using a V-bit?