Platform adhesion issues

This is the place to discuss various hardware. Topic include:
- Display devices (Projectors, Lasers & etc..)
- Microcontrollers & RAMPs boards
- Power supplies
- Z-Axis and Tilt assemblies
- etc..
Hobsie
Posts: 1
Joined: Thu Oct 19, 2017 5:18 am

Platform adhesion issues

Postby Hobsie » Thu Oct 19, 2017 9:22 am

Hi All,

I'm near the end of a self designed/built LCD SLA printer made from very similar parts to the Wanhao D7.

However, my first few test prints have all ended up as blobs glued to the bottom of the vat.

I'm using 0.1 FEP on the bottom of my vat and it's tightly strung (sounds like a medium to high pitch drum with a finger flick). My build platform is a scrap piece of 5mm thick aluminium that's been scored with a box cutter and then sanded with 80grit. Both vat screen and plate are cleaned with isopropyl alcohol before test prints.

I'm using Monocure Rapid white and I have a 50W 405nm LED array (identical to the one in a D7 but 50W instead of 30W). I've tried exposure times on the burn in layers between 30seconds and 2 minutes and layer heights between 25microns up to 100microns. Lift speeds have been tested ranging from reasonably slow to snail-with-a-limp pace.

The test model has been a 3D bench. At first just with the flat surface but then again at an upward angle with supports (to reduce possible suction forces).

However, from what I can tell, literally no sticking is happened with the build plate itself at any point in time. Even after just the first burn in layer the hardened resin is stuck to the vat.

After browsing this form and other sources and trying out a bunch of ideas I'm now a bit stuck and looking for some new ideas.

Anyone got any good ideas I can try out?