3D machining issue

[Branchy]

Hi Guys,
I've got a problem with machining the side walls of some of my customers 3D furniture parts. The top surface is smooth and perfect but as the ball end cutter works its way down towards the base of the part, I will invariably have "pitted walls" as shown in the attached file. I have tried just about everything to rectify the problem... raster finishing, combined with offset finishing, changing file types, (STL, OBJ, Rhino 3DM.etc) but still no luck. The size of files have ranged from 250kb to 50Mb just so that all bases have been covered.
I have attached a screen grab of the 3d file of the part we are currently having issues with. The size is only 440kb, seems ok in the software but the results aren't great particularly around the base of the side walls.
Any help would be greatly appreciated.
Cheers
Chris

[Rcnewcomb]

I assume you already have tried the modeling resolution at Maximum (50 x slower) as referenced in this support document: What are the right settings for Model Resolution? That same support page also has a link to a PDF file that explains the Vectric Model Structure

The pixel-based structure that Vectric products use works very well for artistic bas-relief types of carvings. It does have some limitations when it comes to "steep walls" where the Z depth changes sharply in a short distance -- a 90 degree wall being the most extreme example. There are two ways to work around this:
1. Use a 2D toolpath to clean-up the edge. Depending on the design this may be easy or it might be quite complex to set up the vectors you need
2. If the part allows it add a draft angle so the change in Z is spread out a bit more.

Read through the two links I mentioned above and see if that gives you a better understanding of how the software is handling your particular part.

[Branchy]

Hi Randall,
Thanks so much for the reply, It makes a lot of sense.
Yep, tried the shift key when importing the model and improving resolution but it didn't help with the edges.
I'll look further into the links you attached for further insight.
Thanks again Randall.
Cheers

[martin54]

The modeling resolution that Randall is referring to is set when you first set up the job, it has nothing to do with actually importing a component. If you have a very low modeling resolution set in your job set up then importing a high res image will just mean that the imported image also becomes low resolution.

This quick tips video will explain better than I can.

http://support.vectric.com/tips-and-tri ... ideo_id=10

[4DThinker]

If the profile edge shape is the same all around the part, then you can get better looking results using the moulding toolpath. I've pretty much abandoned the 3D Rough and 3D Finish toolpaths for uniform profile edges.

[martin54]

If the profile edge shape is the same all around the part, then you can get better looking results using the moulding toolpath. I've pretty much abandoned the 3D Rough and 3D Finish toolpaths for uniform profile edges.

Plus on a lot of the stuff I have cut it has machined quicker as well

[plcamp]

It could also be a hole in the model and the tool is simply falling into the void.