Generic Sylgard Substitute $37.00 at Amazon

Various topics related to Vat design, construction and coatings.
watsonstudios
Posts: 52
Joined: Mon Jan 13, 2014 7:34 pm

Generic Sylgard Substitute $37.00 at Amazon

Postby watsonstudios » Wed Jan 29, 2014 7:29 pm

This is what I use and it works great and is cheaper than Sylgard. Only 37.00 for the kit.

I have 3 vats that I keep coated. I use the oven method and I can get a usable coat ready in 2 hours. As long as you can keep your oven between 150 -170 deg. Any warmer and you could warp the polycarbonate - unless you use glass, of course.

http://www.amazon.com/gp/product/B0061G208M/ref=oh_details_o06_s00_i00?ie=UTF8&psc=1

The actual Dow Sylgard 184 on Amazon is $52.00.

Jon

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258cj7
Posts: 31
Joined: Mon Jan 06, 2014 9:38 pm
Location: Kentucky, USA

Re: Generic Sylgard Substitute $37.00 at Amazon

Postby 258cj7 » Wed Jan 29, 2014 9:49 pm

"Any warmer and you could warp the polycarbonate - unless you use glass, of course."

That's one of the reasons I switched to glass. Now I can vacuum de-air then oven cure it for 15min @300F (150C).

watsonstudios
Posts: 52
Joined: Mon Jan 13, 2014 7:34 pm

Re: Generic Sylgard Substitute $37.00 at Amazon

Postby watsonstudios » Fri Feb 21, 2014 8:39 pm

Is the entire vat glass or just the bottom? If it's just the bottom, how do you get a thick layer of PDMS on the glass, what do you have on the sides to contain while baking? Curious.

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258cj7
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Joined: Mon Jan 06, 2014 9:38 pm
Location: Kentucky, USA

Re: Generic Sylgard Substitute $37.00 at Amazon

Postby 258cj7 » Fri Feb 21, 2014 10:46 pm

Just the bottom of the vat is glass. It is held in a 2 piece frame of HDPE that clamps onto the glass.

I put 1" blue painters tape around the edge of the glass to make a wall. I pour in the Sylgard, wait for it to level and for the bubbles to go away (or vacuum degass if I'm in a hurry). I bake it in a toaster oven @300deg f for about 15 min. After it cools I remove the tape. There is some adhesive residue left behind but since it isn't near my imaging area I don't worry about it. The slot in my frame is a little too big because I started with a thicker piece of plexi so I run a bead of aquarium sealer around the edge before I clamp the frame together. One of these days I'll get around to making a new frame that is tight enough for the Sylgard to act as its own gasket.

Another advantage to glass is that it is easier to clean off and re use. I had several pieces of Plexiglas that were ruined when the Sylgard failed (tore) and the resin attacked/dissolved it