Cut3d - roughing marks

[rhfurniture]

Hi,
I am getting some very minor marks from the roughing cut, only on vertical edge surfaces, in spite of setting "machining allowance" to 1mm. Does this allowance only apply to Z?
This was using an 8mm ball - no other problems, so it has held up on its axes position.

R,

[rcnewcomb]

Can you post a photo?

[rhfurniture]

Will do Monday.
Thanks, R.

[paco]

Tell us/vectric how large was your project please.

[rhfurniture]

Hi:

35007.jpg
The artefact is about 2mm across, and was part of the roughing cut. The upper vertical machined edge to the left is 50mm high. The whole project is 700mm x 300mm x 120mm approx and was cut with an 8mm ball spiral in Rampf raku-tool board - an easy-cut plastic based cnc modelling board,
R.

[rhfurniture]

Bump - any ideas?
It was a single surface imported to cut3d from rhino via a 3ds file, and worked "fit to material" on page 2 of the wizard.
R.

[pfulghum]

Collet marks?

[Brady Watson]

Ralph,
I'm not familiar with the tooling board that you mention, but my experience has been that some of those composite boards move around a bit as you remove material. It depends a lot on the shape that is being cut out.

Did you use an 8mm ball for the roughing as well as the finishing? If so, did you tell Cut3D that you were using a ball end tool or an end mill? If you changed tools, there is a possibility that there could have been some debris under the zero plate or deviation in Z from the zzero location of the roughing tool.

To answer your question, the 1mm allowance that you specified for roughing is in all 3 directions, not just in the Z.

-B

[paco]

I had a "similar" problem once but it was with a much larger project. The whole (nested) models where over 48"X48". The problem, according to Tony at Vectric, was that I was well over the "proper" resolution for Cut 3D. Like Cut 3D was better suited for smaller scale project. Zooming in at certain angle could reveal the roughing toolpath was cutting "through" the finishing one.

If you assume the tool didn't lost position anyhow and that you material block didn't move then you may want to contact Vectric support to inquire about an issue with Cut 3D.

I'm not familiar with the tool bit you are referring to. If the tool bit shape isn't support by the Cut 3D tool data base, it might be the problem...

Any chance you can upload the Cut 3D file for us to study?

[benchmark]

Ralph,

I am having similar problems with some scrolled keystones that I am making at the moment..... are you getting any machine vibrations when the spindle changes position from a tall vertical edge to a horizontal plane.

My keystones have nearly 1 million lines of code so when I increased the feed speed the jerky motion caused iregular tool marks similar to the those you have shown.

Maybe some slop in the pinnions ?


Paul