SOOOOO, you ruined your PDMS layer in your VAT???
Buy new one? Sure (I do suggest a vat for each resin type you use)
The Resin tank silicone layer PDMS (polydimethylsiloxane) wears out over time. It can also pull away, tear, or cloud causing failed prints.
Lets save the VAT with making a new PDMS layer. Lets show you how to do this.
First you need to remove the old PDMS layer. You can get the spatula and pry up on the vat from a corner. BE CAREFUL to not scracth the acrylic if you can.
Here it is out.
If any of the resin gets on the acrylic be sure to use a little IPA and clean it up. Use a LINT free towel. I use bounty towels and it works well. Coffee filters work as well.
So now lets address what happens if you do scratch the acrylic. I had my PDMS layer tear and some resin cured on the bottom acrylic. Removing it scratched it pretty bad.
You can see it in the middle to the left where the blue is distorted
So what you are going to need is the Novus acrylic polish and cleaner. I got mine from amazon:
I used a sponge pad I got from a 3M headlight restoration I already had. You COULD do it by hand but it will take you forever and this works so well.
If its a bad scratch start with 3 until it is almost all gone, then go to 2, for the fine polish and then 1 is a wipe clean. Do not use a cloth for the cleaning. Use a bounty towel, a lens cleaner sheet, or coffee filer.
Now that the acrylic is cleaned and clear of scratches, you will need to get some sylgard 184. This is the same stuff they put on solar panels. I was about to buy the actual sylgard 184 on amazon (its also backordered a lot) from dow corning:
BUT Paul Yanzick found some on ebay for much cheaper; about half the price. The sylgard from dow corning was backordered for a few weeks so i decided to try the same stuff Paul came upon. You can find it on ebay or amazon from the same seller. Fast shipping!
A side note: One bottle of silicone and 1 bottle of activator we figured can do 5 vats at once, or probably 4 if done separately. You will have some excess that you will lose each time.
I bought bulk because I am testing a lot of resins out and was tearing the PDMS layers.
You will need a 10:1 ratio of silicone to activator
FOR ONE VAT: 80mL of Silicone and 8mL of activator
80mL of Silicone
8mL of activator
Mix the two together in a disposable cup. Mix it well. It will develop a lot of bubbles. This is OK.
Take your empty and clean (of dust too) Vat and put it on a scale.
0 (zero) the scale with the vat on there.
Pour in about 65-70 grams into the vat.
You will now need to level it.
Cover the vat up to keep dust off of it. I printed off a members vat cover and it works well as a dust cover.
I let the vat sit for 2 days to fully cure. Test this by gently poking a corner and see how it feels. It should not be sticking and bounce back if a finger nail is gently pushed into it.
WHAT ABOUT ALL THOSE AIR BUBBLES!?!?!?!?!?
Well this material is designed to self clear the bubbles out.
20 mins after pour
45 mins after pour
I have restored 5 vats with this method and have already been printing on these. I feel these may be a little stronger, but still have to be careful with it.