Good job Tim, excellent, I knew you could do it. Perhaps it was the mixing then? If you noticed what looked like uncured PDMS perhaps that was it? I like using a plastic spoon, as the inside of the container is a bit ruff and could cause wood splinters when mixing up against edge?
And as promised, here's a demo of the "cliff method" using a home made i-beam. Used 3/8 square stock and 1/8 cord stock.
Here's the prototype I-beam with o-rings on ends:
First to level out vat inside oven:
Here's what it looks like before the pour, leveled out on the countertop:
Poured 30ML +3ML .covered with sheet paper, walked away for 20 minutes-
Now leveled out most bubbles gone, (used toothpick to pop last few large bubbles).
Placed in preheated oven @ 275 for 30 minutes:
Cooled down a few minutes, then initial trim:
Go slow, take your time, be careful not to push too hard and cut into the metal surface!
Re-positioned "I-beam" at an angle and took second cut at slight angle:
Here is what is left over:
And here is what the trimmed edge looks like:
(there were a few bubbles that came from underneath I-beam, but OK, nowhere near print area).
Cool down a few minutes, and it's ready to print!
Easy as pie, in one try! PDMS surface smooth as glass, 100% perfect!
First cut was a little uneven, but second one came out super nice. Only one straight cut is required I believe.
You can also check Mike's instructions as well which are located in the HD version literature.
The toughest part for me was to estimate how much pressure to put on the blade, as did not want to dig into the metal with the knife! However these VATS are HARD anodized so it's not so easy to penetrate the surface.
I recommend using an number 11 exacto blade as it's thin near the end.
Make sure you trim the edge BEFORE re-moving the ibeam.. It stuck pretty good, needed pliers to remove it, however the final I-beam design I now stock includes a small handle to make it easy to remove). .
So that's one method of coating, but special "I-beam" required.
Could also be done at lower heat for those who prefer using the 150-175. That would theoretically take twice as long though.
Can also be done without an oven, takes 2-3 days to cure.