topic Searching for a way to generate circular curly-tail toolpaths in Fusion Manufacture Forum

Searching for a way to generate circular curly-tail toolpaths

Anonymous — Wed, 29 Aug 2018 12:13:21 GMT

Hey there,

I am looking for a convenient way to generate a circular toolpath in CAM. Normally I'd opt for a Projection operation to follow the objects contour which is a curved and closed contour. However, this object yields better milling results when being milled in a 90 degree fashion. So I'd want to mill in a 90 degree fashion from the outside of that closed contour, and then, the endmill (now inside that closed contour) should exit back to be outside of that contour without milling the object to then come back from the outside and again hit the object in a 90 degree manner. So basically, only mill from outside-to-inside making contact with the contour/object in a 90 degree manner, go back to outside without any actual milling taking place, approach contour/object again in a 90 degree manner and so forth ...

I could imagine a labor-intense sketch with a spline that sort of looks like a curly tail, making milling contact in 90 degrees.

Is there a smarter way to go about this? Thanks for any help in advance!

cheers

Dominik

Re: Searching for a way to generate circular curly-tail toolpaths

kb9ydn — Wed, 29 Aug 2018 22:22:13 GMT

I think I sort of understand what you're trying to do, but without at least a picture of the shape you want to cut I would only be guessing. Even better would be if you could attach a sample file.

Re: Searching for a way to generate circular curly-tail toolpaths

Anonymous — Thu, 30 Aug 2018 08:45:56 GMT

The purple line is the contour I want to mill and I would normally follow. Since The contour continues for quite a bit, a manual approach like this is labor-intense. Also, I am not sure how good I can control the spline to fulfill my wishes of 90 degree approaches and maintaining equal distances between entry/exit spots.

Re: Searching for a way to generate circular curly-tail toolpaths

kb9ydn — Thu, 30 Aug 2018 22:25:30 GMT

@Anonymous wrote:
The purple line is the contour I want to mill and I would normally follow. Since The contour continues for quite a bit, a manual approach like this is labor-intense. Also, I am not sure how good I can control the spline to fulfill my wishes of 90 degree approaches and maintaining equal distances between entry/exit spots.

Ok, that's not at all what I was thinking so it's good that I asked. What it looks like you want to do is to mill in little bites; approach from 90 degrees and enter the material, cut over a little, and then exit out again. As such there isn't anything in Fusion that will do exactly that. Probably the closest thing would be the adaptive strategies, which are intended to keep a constant load on the tool by cutting with a path that produces a constant engagement angle with the part.

So what is it you're trying to accomplish with the method you've described? It would be quite inefficient and I can't think of any situation where this would be beneficial. It would be helpful if you could show the whole part. Or if that's not possible at least something that's similar. I'm thinking there's probably another way to get where you want to go.

Re: Searching for a way to generate circular curly-tail toolpaths

Anonymous — Fri, 31 Aug 2018 07:46:23 GMT

Two reasons.

Entering from the outside will possibly cause less fibre delamination on the outside surface of the part. Secondly, less stress on the part (and stress toward the middle rather then along the contour), possibly resulting in less bending/ moving on my fixture. The part I am milling is <1mm thick and thus can be a bit finnicky. These are both hypothesis I wanted to test by doing a few dozen tests. Just wanted to check if there is anything like it in Fusion I am missing, but it appears to be a one-off approach (and it very well might be not measureably better after all). The image I shared is from the part itself, it just continues like that and comes round from the bottom to close the contour.

Thanks for your efforts in any case. 🙂

Re: Searching for a way to generate circular curly-tail toolpaths

randyT9V9C — Fri, 31 Aug 2018 07:52:15 GMT

I can see that this could be really handy. You should post this to the IdeaStation along with your example screen shots. If it gets enough interest it may be added to Fusion 360.

Re: Searching for a way to generate circular curly-tail toolpaths

djowen40 — Thu, 06 Sep 2018 06:04:53 GMT

As @kb9ydn mentioned a 2D adaptive trapped in a "slot" will look something like what you want (see screen shot below). You can make an artificial slot by creating an offset sketch of the profile you are cutting.