CAD Forum

[Leon]

Hi

(not sure if nesting is strictly the right term). I have a part to profile out of acrylic sheet. The part has several internal holes that need to be milled before the outside is cut (eg the gasket example in the sample tutorial that comes with CAM 2.0).

Can the internal holes be forced to cut before the outer profile? Or do I have to have these on separate sketches?

Thanks

[Leon]

I have played around more with the Flat Area Selections and I can now choose to pocket holes before I profile the edges. However, when I go to profile the edges, it still wants to go inside and profile the internal holes that I previously cut using the Hole Pockets.

(As an example, consider the gasket example or a simple flat washer. I need to cut the centre material away first before I cut the outside profile. When I cut the outside profile I want to avoid going back inside to try and re-cut the inner circle a second time - the part is now loose from the stock and would be damaged if I recut it.

Is there a way that I can select only the outside edges of the profile to be cut and to ignore the inner features?

Thanks

[Leon]

Any ideas on this?

I have tried putting the internal holes on another sketch and then setting them as Avoid Regions when I try and machine the outer regions but it still wants to machine the internal holes a second time

Even if I were to get the internal holes working on a separate sketch it does seem a bit complex - I would assume that there would be some option to just cut the internals first.

[caddit]

Hello Leon,


Sorry about the delayed response.

In Alibre CAM, a contour operation uses CAD sketch information as the basis of what to cut in CNC. If you look closely at the gasket example which you mention earlier, you will indeed see that the two different profile cuts are indeed created from two different sketches.

It helps to design your parts with CAM in mind to start with, in other words.

Another possibility would to create "avoid regions" over the holes and include them in a second op. Maybe try that and see if it helps?
_________________
CAD Software Support
progeCAD Software Asia Pacific
Alibre Australia, PTC and MathCAD

[Leon]

Thanks Ben. I see your point about sketching with the machining features in mind from the start. Is there an easy way to insert a new sketch? I seem to get a request sometimes after saving to insert a new sketch or edit a new one but I am not sure how to get this command when I want it!

Regards

[caddit]

Hi Leon,


How to create a new sketch? You can create a new Alibre sketch any time, by clicking on the "sketch" icon , pick a planar reference and begin a new sketch, while in either CAD or CAM browser mode..

This icon is located by default toward the top right of the drawing window.
_________________
CAD Software Support
progeCAD Software Asia Pacific
Alibre Australia, PTC and MathCAD

[Leon]

Ah, I see what is happening. When I tried this before I was expecting it to say "Do you want to add a new sketch or edit an existing one". I now see that you just click this and start drawing and it adds "Sketch 2" to the browser after you have commenced drawing....

Cheers

[caddit]

Sometimes it's just too easy
_________________
CAD Software Support
progeCAD Software Asia Pacific
Alibre Australia, PTC and MathCAD