Creating repeated holes through a sphere

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abasel
Posts: 105
Joined: Sun Sep 02, 2018 12:22 am

Creating repeated holes through a sphere

Postby abasel » Sun Jul 05, 2020 10:51 pm

What is the approach that I should follow to punch a series of shaped holes through a sphere e.g. trying to achieve the top part of this rattle.
Holes.PNG
Holes.PNG (159.65 KiB) Viewed 226 times
Reynard1066
Posts: 27
Joined: Sun May 10, 2020 7:27 am
Location: Scotland

Re: Creating repeated holes through a sphere

Postby Reynard1066 » Mon Jul 06, 2020 1:24 pm

Set up a few Datum Planes at the correct place and angle.
Draw sketches of the apertures and pocket through the hollow hemisphere.
A polar pattern for each pocket.
Add in some guessing for hole shape and position.
Attachments
Rattle Top.png
Rattle Top.png (53.46 KiB) Viewed 184 times
abasel
Posts: 105
Joined: Sun Sep 02, 2018 12:22 am

Re: Creating repeated holes through a sphere

Postby abasel » Mon Jul 06, 2020 9:37 pm

Reynard1066 wrote:
Mon Jul 06, 2020 1:24 pm
Set up a few Datum Planes at the correct place and angle.
Draw sketches of the apertures and pocket through the hollow hemisphere.
A polar pattern for each pocket.
Add in some guessing for hole shape and position.
Awesome, thanks :)
abasel
Posts: 105
Joined: Sun Sep 02, 2018 12:22 am

Re: Creating repeated holes through a sphere

Postby abasel » Mon Jul 06, 2020 10:36 pm

I am battling to place the Datum planes. Could you please give me a screenshot of your Plane Parameter settings so that I can compare?

I tried adding a datum plane and then move it 40mm along the y-axis but nothing happens
DatumPosition.PNG
DatumPosition.PNG (63.23 KiB) Viewed 127 times
Attachments
Rattle.FCStd
(8.49 KiB) Downloaded 2 times
vocx
Posts: 5002
Joined: Thu Oct 18, 2018 9:18 pm

Re: Creating repeated holes through a sphere

Postby vocx » Tue Jul 07, 2020 3:35 am

abasel wrote:
Mon Jul 06, 2020 10:36 pm
...
I tried adding a datum plane and then move it 40mm along the y-axis but nothing happens
The coordinates are local to the attachment, so you may have to move the X or Z coordinates instead of the Y coordinate.
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Reynard1066
Posts: 27
Joined: Sun May 10, 2020 7:27 am
Location: Scotland

Re: Creating repeated holes through a sphere

Postby Reynard1066 » Tue Jul 07, 2020 7:57 am

Yes datum planes do seem like trial and error to see which way they move, but you work something out eventually.

I have been struggling to get the file size below the 1Mb mark. Using compression level 9 seemed to do it.

File attached.
Attachments
Rattle Top.FCStd
(982.14 KiB) Not downloaded yet