More irritating problems when machining a dome shaped model

[Soapyjoe]

Hi everybody.

I am attempting to make a set of domed shaped Pentagons to produce a Dodecahedron that closely resembles a sphere.

With great assistance from the forum.... I now know how to calculated the depth of the sphere etc.,etc.

However, when I am machining the roughing tool path I get quite a number of annoying pauses (where the tool lifts and lowers again for no apparent reason) This happens quite frequently especially when the tool is getting close to the corners of the Pentagons....

The pentagons have sides of 70 mm.
I am using a 6 mm roughing tool with a step over of 2 mm cutting 0.5 depth per pass.
I convert the Vectric software with WinPC-NC USB software to run on a German CNC Step High Z CNC machine.

Any ideas?

[Phil]

I'm guessing that you created an initial component and copied that component as many times as needed to produce the Dodecahedron. So, when you created the toolpath it was based on many individual components . Assuming I am correct you need to group all of the components into one component and create a new toolpath based on the grouped components.
Hope this helps.

Phil

[Soapyjoe]

Hi Phil,
The domed Pentagons are each made individually from one piece of wood (see below)
The problem occurs when I am roughing out the shape and it nearly always occurs in the corners.
I guess I can live with it but do like to know why things happen.
When running the programme in Vectric the simulation works fine but the problem occurs when I run it for real .... which make me feel that the glitch happens between the Post processor and the CNC. I have never experience anything like it before.

Running previous programmes everything is fine ... To my mind the post processor obviously does not like something in the Vectric drawing ... this gives the CNC a headache

I just wonder if anybody has experienced similar

[dealguy11]

Do you have a zero plane? I think a situation where this happens is when the boundary vector defining the machined area goes very slightly beyond the component, which is easy to make happen because the pixels in the model may not exactly conform to the boundary vector. Because this is undefined territory in the model, Aspire lifts the cutter because it doesn't know what's there. If you include a zero plane, then the area beyond your component now has defined pixels and the cutter should not lift. If you already have a zero plane, then it's obviously something else.