Thickening up Tin Based Silicone

[Got Maul]

Its been awhile since I've used the slather on technique :lol but after the beauty coat, I wanted to get a nice thick pasty coat. What are some thickening agents you guys have used to get that silicone nice, thick and sticky ?

Keep in mind, I am using a tin based silicone (common blue stuff).

 

[Darth Mule]

Cab-O-Sil is the standard. It's nasty stuff though. Fumed Silca, very fine powder. Gets airborne easily. Can mess you up if you inhale any. Use outdoors and wear your goggles and respirator. Seriously. This stuff is as bad as metal powders.

Smooth-On makes some alternative thickening agents for their products (http://www.smoothonsecure.com/store...82_31&osCsid=8a1b77b24e7ce28d922ea77f297d8950)
I think most silicone companies do as well.

 

[Draven]

Ask your silicone supplier for a liquid based thixotropic agent.

You add it (percentage varies, but the one we use is 5% by weight) at the mixing stage and it gives you a very thick, trowellable(?) rubber.

It also makes the cure time a little faster too!

Draven

 

[Got Maul]

Ask your silicone supplier for a liquid based thixotropic agent.

You add it (percentage varies, but the one we use is 5% by weight) at the mixing stage and it gives you a very thick, trowellable(?) rubber.

It also makes the cure time a little faster too!

Draven

I heard this works only for platinum based silicone though. Trust me, I WANTED this to work !

Cabosil - yup, that's the stuff I used before. Really really nasty. (sigh)

 

[TK648]

A material called PolyFiber 2
from www.PolyTek.com
works great for silicone and polyurethane resin
and far safer then the EVIL Cabosil stuff

 

[MR BARLOW]

Hey GotMAul


Ixe used Thixo agent on anything from GI 1000 to 1065 etc....
That plus ultrafast catalyst if you choose to use it , although ultrafast enables a bit of shrinkage and overtime aids the silicone in becoming brittle.

http://www.monsterclub.com/silicones/additives.html

Good for brushups

R

 

[vaderman1701]

Smooth-on uses a product called Thyvex to turn there tin based silicone into a brushable product.

Scott

 

[JtotheP]

It's also a good idea to tint the next layer you put on a different color than the previous layer with a specific tint from your silicone provider. It will tell you how well you cover the previous layer and give you your consistent coverage.

 

[Got Maul]

Thyvex ? Sounds interesting...

 

[TK648]

New Tin Cure silicone from Smooth-On


Mold Max Stroke™ is a brushable tin silicone rubber that self-thickens for making fast brush-on molds of almost any model. Properly applied, it will hold a vertical surface and will reproduce the finest detail. Mixed 100A:10B by weight, rubber quickly develops thixotropy and can be applied with a brush or spatula. Working time is 20 minutes, re-coat time is 45 minutes and cure time after the final layer has been applied is 16 hours at room temperature. Mold Max Stroke™ silicone will not stick to most surfaces and will cure with negligible shrinkage to a strong, flexible Shore 30A rubber. 4 thin layers is all that is necessary to make a strong and durable production mold for casting wax, gypsum, concrete or resins (urethane, polyester, etc.). Applications include reproducing sculpture, architectural restoration, making candle molds, casting pewter, etc.
Thi-Vex™ II Silicone Thickening Agent
THI-VEX II is made especially for thickening Smooth-On's Mold MaxÔ 10, 20 & 30 (tin-catalyst), Smooth-Sil 920, 930, 940 & 950 (platinum-catalyst), Dragon Skin or Ecoflex (platinum catalyst) silicones for vertical surface application (making brush-on molds). Different viscosities can be attained by varying the amount of THI-VEX II. Read the Technical Bulletin for full details.

Fast Cat™ Cure Accelerator for Mold Max
FastCat™ 30 silicone rubber catalyst will accelerate the cure time of Mold Max™ 30 silicone rubber. Used in place of (or in combination with) Mold Max™ regular Part B catalyst, FastCat™ will reduce the demold time from overnight to as little as 30 minutes. Note: working time is reduced in proportion to the amount of FastCat™ added. Read the technical bulletin for each specific FastCat™ for full details.

Cryptolyte™ UV Glow Additive for Urethanes and Silicones
Cryptolyte™ is a translucent liquid additive that causes cured Smooth-On silicone rubbers, urethane rubbers, plastics or foams to glow a bright blue under a focused ultra violet light source (blacklight). You will not see the glow effect without an UV light source. When mixed at low percentages it will not affect clarity or color of material. For example, Cryptolyte™ can be added to Crystal Clear™ water clear resins and the glow effect will not be evident until the casting is illuminated by a UV light source.

Important: Best “glow” effect is realized when Cryptolyte™ is added to clear (i.e. Sorta Clear silicone or Clear Flex urethane rubber) or translucent materials (i.e. Smooth-Cast 325 resin). Applications include special effects, Halloween mask and prop making, theme displays and security (you can make parts that are virtually undetectable in normal light but glow under UV black lighting).

 

[Neon Sentry]

Oooh, UV Glow. That sounds nifty. An all black BatSuit illuminating blue at a party... sounds like fun.

 

[clayslinger]

Silicone Inc. has GI 184 brushable.

The thickening agent is in the activator.
You can use the regular GI 1000 activator with this base for poured molds.

I spoke with their tech guy and he suggested a 50-50 mix of Ultrafast cat and the GI 1000 activator with this base for your print coat. Approx. 20 min work time. Recoat in 1 hour.

Then the 184 activator and base for build up. 15 min work time.

I have some on order now so I can't give any first hand critique.

Good luck with your project!
Chuck...