topic 3D Chamfers either gouge parts, or don't work at all. Am I the problem? in FeatureCAM Forum

3D Chamfers either gouge parts, or don't work at all. Am I the problem?

j.labdik — Sun, 19 Sep 2021 20:36:46 GMT

Hey, I've been trying to get 3D chamfers to work with a ball mill for a bit now in featurecam, with no success so far. 2D chamfers are great, and they work okay with a chamfer mill. But for some reason, I can't seem to get the 3D to work properly at all. The "help" section for featurecam basically tells you nothing at all about 3D chamfers.. I've attached the most simplified version of the problem to this post. Can someone tell me why in the world it gouges so badly? tip offset seems to make it worse, and you cant go negative which sucks. Using a solid model doesn't get me anywhere either considering when I do that, it never works at all - and the error message just says unable to handle error processing. No info at all about what's causing the error. I'm at a loss here....

Re: 3D Chamfers either gouge parts, or don't work at all. Am I the problem?

ChristopherMarion — Mon, 20 Sep 2021 13:18:05 GMT

Hi @j.labdik

Can't say I've used this feature type too often, but here is a better explanation of what 3d chamfering provides.

3d Chamfer Overview

I tried to view your fm file, but there was no solids or any surface data. Please review the documentation and then reattach the fm file if you require some additional help.

Thanks,

Re: 3D Chamfers either gouge parts, or don't work at all. Am I the problem?

j.labdik — Tue, 21 Sep 2021 00:22:02 GMT

Just simulate the file I uploaded with 3D mode. You'll see what I'm talking about. The ball endmill approach to "3D chamfer" is totally screwed up and gouges into the part. It pushes the ball mill way too deep regardless of what you do. The file I uploaded is the most simple way you could program this, it's a circle curve the same size as the stock, and I made a chamfer feature on the end of it. If you simulate it with 3D mode, you can see the ball endmill plunging waaaaaaaaaay too deep into the stock. The stock origin is the end of the part, and you should really only see a tiny chamfer get cut onto it.

Your link to the overview is the same thing I found, which literally explains nothing. The featurecam help document is really only as good as the toilet paper it's printed on.

Re: 3D Chamfers either gouge parts, or don't work at all. Am I the problem?

ChristopherMarion — Tue, 21 Sep 2021 12:37:08 GMT

Hi @j.labdik

So I can confirm your issue, but I do not know how to resolve it. It definitely looks like it isn't doing what it should.

I suggest you send this into development directly, since they do not monitor the forums very often.

To do this, log into your Account. Then:

Once you are logged in, press the black question mark at the bottom right of the screen
Choose the option Post Purchase Support
Then, choose Help Using My Software
Choose FeatureCAM Products from the dropdown
Place a reason as to why you need help. Put in something like "Issue with 3d simulation"
Once you press the search, there will be some general help articles, but you will want to press the "All other customers" at the bottom of the page.

Once you get to that point, just fill in all of the information about what you are experiencing with FeatureCAM. That should generate a case number and you will get a response that someone will contact you. You should get contacted in a day or so.

If you need help with this, let me know and I can give you a hand.

Thanks,

Re: 3D Chamfers either gouge parts, or don't work at all. Am I the problem?

chris.coleQDYFL — Tue, 21 Sep 2021 12:50:14 GMT

I have always had better luck with 3D chamfers when I use part surfaces and/or check surfaces. I think the feature has a better understanding of the tool's position in 3D space this way. Otherwise, I think it's just going to offset the curve and cut too deep.

In this case, it's easy. I just made a cap surface from your curve and added it to the Part Surfaces. Check out the attached file.

And yeah, the Help file isn't very useful. Let me know if this helps.

Re: 3D Chamfers either gouge parts, or don't work at all. Am I the problem?

ChristopherMarion — Tue, 21 Sep 2021 13:11:14 GMT

@chris.coleQDYFL

Was wondering what the part surfaces and Check surfaces were for in this feature 🙂

Thanks for the insight Mr. Cole....helpful as always.

Cheers,

Re: 3D Chamfers either gouge parts, or don't work at all. Am I the problem?

shawn6R83D — Tue, 21 Sep 2021 13:46:23 GMT

I have used this toolpath successfully a few times. There is art involved with the tool path. I have attached my work around for this issue to this post. If you are only chamfering .02 you need to use the smallest tool possible. I always go with .125 ballnose. I offset the tool tip as much as I can and try and use a small section of the ballnose. The simulation will look weird, but when you take it to the machine tool it will do what you want it to do. You may have to play with the numbers a bit but it will work. Using a small tool is the most important thing to do. I hope this helps.

Shawn

Re: 3D Chamfers either gouge parts, or don't work at all. Am I the problem?

dspees — Wed, 22 Sep 2021 14:36:03 GMT

Here is another option for surfacing a chamfer. You can use a side feature set at an angle.

Re: 3D Chamfers either gouge parts, or don't work at all. Am I the problem?

j.labdik — Wed, 22 Sep 2021 15:13:07 GMT

I knew I was the problem.... You're right. The part surfaces on the top of the chamfer fixes it. The file I'm actually working on has much more complex geometry than what I had shared. Used your approach of picking the right surfaces and it's working. Thanks for your help!

Re: 3D Chamfers either gouge parts, or don't work at all. Am I the problem?

j.labdik — Wed, 22 Sep 2021 15:14:36 GMT

I had never considered using the side feature approach... man that's interesting. Thanks for your input on this! Chris' solution worked perfectly for the actual part I'm working on, but this is something I'll be using in the future for sure...