Odd shapes with undercuts.

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Dark Engineering
Posts: 5
Joined: Wed Apr 08, 2015 11:54 am
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Odd shapes with undercuts.

Postby Dark Engineering » Fri Apr 17, 2015 10:59 am

Overall I have been very happy with my LittleRP printer. I have noticed an issue or two with it.

The one I want to address here is odd warping when making undercuts. I printed this d10 with the 0 side as bottom in CW. I made a base for it and it was printed with around 8 supports attached to the 0 side.

I have noticed that even level flat sections with supports to not fully cure. I would appreciate any help and or suggestions on how to correct this from happening.
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20150416_230757.jpg

Scatterplot
Posts: 119
Joined: Mon Jan 12, 2015 12:09 pm
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Re: Odd shapes with undercuts.

Postby Scatterplot » Fri Apr 17, 2015 12:01 pm

I know it sounds weird, but try printing it with one of the points as the base. I think the issue is that flat spots, when supported only by a few posts, bend inwards when detaching from the PDMS layer. If you orient it such that it starts with a point, I think it will be able to build the shape by starting with a small point and working upwards.

Imagine the first flat layer that gets printed- a 50 micron thick (less than a sheet of paper) getting peeled off of the PDMS. It won't come off evenly and it will bow inwards. It's too thin to spring back to shape, so it ends up getting rounded out.

Basically, I think the issue is with large flat layers with no backing to them.

Dark Engineering
Posts: 5
Joined: Wed Apr 08, 2015 11:54 am
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Re: Odd shapes with undercuts.

Postby Dark Engineering » Mon Apr 20, 2015 1:20 pm

I will try this out probably tomorrow. This seems like a good reason that is easy to visualize what is happening here. Thanks for the reply.


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