Path of pocket with inclined sidewalls

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pleid
Posts: 3
Joined: Tue Jan 24, 2017 1:16 pm

Path of pocket with inclined sidewalls

Postby pleid » Tue Jan 24, 2017 4:50 pm

Hi there,

is there a way to make a path of a pocket with inclined side walls using the path module without using the surfacing tool?

I have something like this in mind:
pocket-inclined-sidewalls.png
pocket-inclined-sidewalls.png (16.47 KiB) Viewed 415 times


Thanks a lot, best
Patrick
herbk
Posts: 336
Joined: Mon Nov 03, 2014 3:45 pm
Location: Windsbach, Bavarya (Germany)

Re: Path of pocket with inclined sidewalls

Postby herbk » Tue Jan 24, 2017 6:00 pm

Hi Patrick,
for "something like this" you need a 5 Axis machine, Path WB makes (in this time) only pathes for 3 Axis machines. :lol:
Gruß Herbert
sliptonic
Posts: 596
Joined: Tue Oct 25, 2011 10:46 pm

Re: Path of pocket with inclined sidewalls

Postby sliptonic » Tue Jan 24, 2017 7:45 pm

pleid wrote:Hi there,

is there a way to make a path of a pocket with inclined side walls using the path module without using the surfacing tool?

I have something like this in mind:
pocket-inclined-sidewalls.png

Thanks a lot, best
Patrick


This shape could be approximated with a 3 Axis machine and a ball end mill. The path is theoretically possible with the tools we have now but we don't have an operation that can do pocketing on inclined walls yet.
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bill
Posts: 156
Joined: Fri Jan 09, 2015 9:25 pm

Re: Path of pocket with inclined sidewalls

Postby bill » Wed Jan 25, 2017 4:19 am

pleid wrote:...way to make a path of a pocket with inclined side walls using the path module without using the surfacing...

Hard to say just looking at the png.
What is the incline angle?
What are the dimensions?
With the right tooling, I think it is possible depending on the dims!
What is your stock material: Alum, steel, plastic, brass, etc. ?
Can you post the file? -- I would like to take a crack at it; I can think of one possible way to complete.
Tolerances?

Just remember, FreeCAD_Path is not a computerized machinist; its another set of tools at the machinist's disposal!
pleid
Posts: 3
Joined: Tue Jan 24, 2017 1:16 pm

Re: Path of pocket with inclined sidewalls

Postby pleid » Wed Jan 25, 2017 7:27 am

Hi all, thanks a lot for your replies!

I am totally aware, that I will only get an estimation of the surface with my 3-axis machine, and that is fine for me. A rough, stair-cased surface is fine form me as well.

I have attached the file, but I will not make exactly this part. It is just a demo structure for me to compare different CAM programs.
In the end I would like to do a more complicated structure but with inclined walls. The final part will be made out of PVC.
Attachments
pocket-v04.fcstd
(18.05 KiB) Downloaded 12 times
herbk
Posts: 336
Joined: Mon Nov 03, 2014 3:45 pm
Location: Windsbach, Bavarya (Germany)

Re: Path of pocket with inclined sidewalls

Postby herbk » Wed Jan 25, 2017 7:31 am

Hi Bill,
in my mind and like sliptonic wrote, more like abroximate to cone isn't possible with a 3 Axis machine. Also if you have a tool with corresponding angle it does not fit in the corners.
If you accept a abroximate, which means there are steps (Surface roughness) on the surface of the cone, it works if you make the solid (part) with this steps to. Then you have horizontal levels and you can use the pocket operation for it.
I did it one time at this way, but its a lot auf work to make the solid so much steps, that it's realy is a abroximate.... ;) ;)
Gruß Herbert
realthunder
Posts: 110
Joined: Tue Jan 03, 2017 10:55 am

Re: Path of pocket with inclined sidewalls

Postby realthunder » Sun Jan 29, 2017 12:38 pm

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.

Simply select 'Cube' in the tree view, then 'Cut'. Go to Path, select 'Create area from shape'. Change Operation to 'Difference', Set SectionCount to -1, PocketMode to ZigZag. Then select the FeatureArea in treeview, and click 'Create Path from shape' on Path toolbar. Done!
Screenshot from 2017-01-29 20-28-02.png
Screenshot from 2017-01-29 20-28-02.png (238.46 KiB) Viewed 301 times
chrisb
Posts: 1666
Joined: Tue Mar 17, 2015 9:14 am

Re: Path of pocket with inclined sidewalls

Postby chrisb » Sun Jan 29, 2017 1:27 pm

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.
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bill
Posts: 156
Joined: Fri Jan 09, 2015 9:25 pm

Re: Path of pocket with inclined sidewalls

Postby bill » Sun Jan 29, 2017 3:38 pm

What is the computation time to generate this Path, Mr Thunder?
I dont have Path.Area installed. Could you generate a path for the inverted LOFT Object from the stock block below?
LOFT.png
LOFT.png (14.39 KiB) Viewed 279 times

Thanks!
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bill
Posts: 156
Joined: Fri Jan 09, 2015 9:25 pm

Re: Path of pocket with inclined sidewalls

Postby bill » Sun Jan 29, 2017 3:59 pm

pleid wrote:is there a way to make a path of a pocket with inclined side walls using the path module without using the surfacing tool?

Yes, a 45 degree cutting tool; Not as cool as 3D Surfacing, but faster and more accurate per the speed increase.

vfin.png
vfin.png (19.83 KiB) Viewed 274 times


pocket-vfin.fcstd
(25.84 KiB) Downloaded 7 times