Build Your Own SLA/SLS

Hi!

I recently built my own DLP based bottom-up printer using a FlexVat consisting of a original DuPont FEP/Teflon film (50um). There's no extra acrylic in between and just the highly tightened film itself. I have no special peel mechanism but only the Z-axis movement. My prints come out well after many failures. After reading in this forum I was able to fix the issues. However, I still have sounds during release which I think are strange.

Is is normal that the release from the printed object off the FEP film makes a kind of cracking sound? The loudness depends heavenly on the area to be released.
The film gets pulled up like 3mm before its released. I thought Teflon FEP film has a special coating so nothing adheres to it!?

Is that sound related to too much exposure or any other issue? I cannot find good videos on the net including great audio.
Might that become better with a peel mechanism like here: https://www.youtube.com/watch?v=-K0bb5_Pjkw (around 0:50)?

Resin: Fun To Do Standard Blend in black.
Object: http://www.thingiverse.com/thing:291323 (scaled down a bit)

Thanks,
radi2k

It sounds like you could use more tension on your teflon, it shouldn't pick up 3mm before releasing.

When it's tensioned, and you tap it, does it sound like a drum?

Hi AndersonTa,

it did sound like a drum but probably not high pitched enough. I tightened it a bit more and prints were getting much better. Also the release sound is almost gone now. However, a redesign is needed for my FlexVat since there is no more room left for more tension. I'll also integrate a separate peel mechanism to improve it even more.

Thanks,
radi2k