Path of pocket with inclined sidewalls

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herbk
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Re: Path of pocket with inclined sidewalls

Post by herbk »

Hi Bill,
Yes, a 45 degree cutting tool
No, a 45 degree cutting tool can not produce this "corners".
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Re: Path of pocket with inclined sidewalls

Post by chrisb »

herbk wrote:Hi Bill,
Yes, a 45 degree cutting tool
No, a 45 degree cutting tool can not produce this "corners".
Ok, it should say ... a cutting tool of appropriate angle ...
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Re: Path of pocket with inclined sidewalls

Post by herbk »

Hi Chris,
a cutting tool with an angle has always on the upper side a biger diameter as at the bottom. For that reason you never will get rounded edges with same campfer diameter at top and bottom.
ecken.jpg
ecken.jpg (18.65 KiB) Viewed 2013 times
The "corner" like on the pic you con only get with an regular (rectangular) toolshape and
a with a Machine wich can turn the tool to the anglr you want
b (on a machine with omly 3 axis) a gcode which moves all 3 axis in one line.
Last edited by herbk on Mon Jan 30, 2017 3:53 pm, edited 1 time in total.
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Re: Path of pocket with inclined sidewalls

Post by chrisb »

herbk wrote:Hi Chris,
a cutting tool with an angle has always on the upper side a biger diameter as at the bottom. For that reason you never will get a rounded edges with same campfer diameter at top and bottom.
You are right in both points. But if you look at the pocket the chamfer has different diameters at the top and the bottom. Of course you must not go straight down, but if you look at the path of realthunder you can see that the steps further down do not go as far to the outside as those at a higher level.
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Re: Path of pocket with inclined sidewalls

Post by sliptonic »

realthunder wrote:I thought it was going to be easy for my new Path.Area. Boy, was I wrong. Those fillet edges turn out to be BSpline. I've never really tested non-circular curves. It took me a whole day to fix. It was those OCC bug thing, I think, which is why Part didn't use BRepAlgoAPI_Section for cross section. I should have read their code more carefully. Anyway, here you go. You can try my branch at here.
Now we're talking! That looks very interesting.

I've pulled your current branch and I'm trying to duplicate your results but I get this error regardless of what I do:

Code: Select all

Exception (Sun Jan 29 21:24:16 2017): shape is not planar 
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Re: Path of pocket with inclined sidewalls

Post by realthunder »

chrisb wrote:Is this operation "Shock and Awe" :lol: ? I think it is time to get accusomed to this Git-stuff.
Is there a possibility to change the direction of the diagonal path segments as well? For production I would like to have at least four goes, one for each side.
By direction, you mean the zigzag direction? If so, yes, in FeatureArea, there is setting for zigzag angel. You can try other mode of pocket as well, such as the Offset mode, more conventionally known as Contour mode, I think. With proper setting of Retraction Threshold in FeatureShape, we get the same keep tool down effect as zigzag.

Right now, FeatureShape may break zigzag path into segments for optimization, which makes it sensitive to start position, and often gets worse result. It'll be fixed soon. Offset mode is not affected.
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Re: Path of pocket with inclined sidewalls

Post by realthunder »

sliptonic wrote: Now we're talking! That looks very interesting.

I've pulled your current branch and I'm trying to duplicate your results but I get this error regardless of what I do:

Code: Select all

Exception (Sun Jan 29 21:24:16 2017): shape is not planar 
How do you select the shapes? To create FeatureArea, you must select the solid shape in the tree view, not the 3D view. If you select in 3D view, FeatureArea will add the selected subelement (face, or wire), instead of the whole solid.

Also, please sync the git often. Path.Area is quite volatile at the moment.
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sliptonic
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Re: Path of pocket with inclined sidewalls

Post by sliptonic »

realthunder wrote:
sliptonic wrote: Now we're talking! That looks very interesting.

I've pulled your current branch and I'm trying to duplicate your results but I get this error regardless of what I do:

Code: Select all

Exception (Sun Jan 29 21:24:16 2017): shape is not planar 
How do you select the shapes? To create FeatureArea, you must select the solid shape in the tree view, not the 3D view. If you select in 3D view, FeatureArea will add the selected subelement (face, or wire), instead of the whole solid.

Also, please sync the git often. Path.Area is quite volatile at the moment.
Yes, I'm selecting in the tree. Currently running git commit: 65f01daee28bc51f2e98878ad2b4fde3fee1efe0
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Re: Path of pocket with inclined sidewalls

Post by realthunder »

sliptonic wrote:Yes, I'm selecting in the tree. Currently running git commit: 65f01daee28bc51f2e98878ad2b4fde3fee1efe0
That's strange. Here is my file. I just redo all the steps I described. No problem here. Could you please send me your file.
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pocket-v04.fcstd
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Re: Path of pocket with inclined sidewalls

Post by sliptonic »

Yes. Got it going. Problem was my own misunderstanding about how to set it up.

I was able to get some very nice pocket paths out of it that wouldn't be possible otherwise. :D
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