Any inexpensive Silicone sources out there?

[Fetthunter]

Hey guys! I normally buy my Silicone from Smooth-On. I'm working on a project and need to make 2 LARGE molds for 2 parts that I need to cast. As these are LARGE molds, I'm looking for a supplier that might be a *bit* cheaper than Smooth-On.

Can anyone recommend an inexpensive source for a tin-cure, 1:1 mix Silicone?


Thanks!

J

 

[JtotheP]

Try Reynolds Advance Materials in Orlando, Florida. They carry smooth on, but have cheaper alternitives.
http://www.reynoldsam.com/

 

[sycor]

I have no idea what their prices are like but I know another member here use www.siliconesinc.com but I think you have to call to order

 

[Fetthunter]

Thanks, guys!

Any others?

 

[fettster]

just remember that the cheaper the silicone, the more it is actually filler therefore it wont last as long.

are there many undercuts? could you do a multipiece fiberglass mold? dirt cheap then

 

[foxbatkllr]

jgreer.com

 

[Matsuo]

I should also note that you may want to look into getting a higher durometer silicone if you are as you say making large molds.
General purpose silicone run about 15-25 durometer, like for instance GI-1000 or HS-2 . They are fine in most instances but you will find that they tend to crush or deform under their own weight in large molds. A carefully thought out mother mold or mold box which supports the mold will help. If it's a tall mold like for a gun barrel, stood on end it will sag without support making a shorter barrel. Any large mold not made of a higher than normol durometer will sag without support when stood on end..just be aware of that.

For really big molds I use a high durometer rubber of 30 or above, I have a really hard platinum cure formula which is a 40 that I use when tolerances are important and I want to minimize shrinkage.

M

 

[Fetthunter]

just remember that the cheaper the silicone, the more it is actually filler therefore it wont last as long.

are there many undercuts? could you do a multipiece fiberglass mold? dirt cheap then

No undercuts on either, so I could just coat the surfaces with silicone, then back the silicone once cured with fiberglass, I 'spose... That would make it much cheaper...

 

[Fetthunter]

jgreer.com

I've bought resin from them in the past and forgot that they sell Silicone, too! :wacko :lol

Their resin works well. Not wild about how fast it kicks, but with my small molds, it's workable. On something large, their resin would be scary to work with. :eek I'll look into their Silicones, though.

 

[Fetthunter]

I should also note that you may want to look into getting a higher durometer silicone if you are as you say making large molds.
General purpose silicone run about 15-25 durometer, like for instance GI-1000 or HS-2 . They are fine in most instances but you will find that they tend to crush or deform under their own weight in large molds. A carefully thought out mother mold or mold box which supports the mold will help. If it's a tall mold like for a gun barrel, stood on end it will sag without support making a shorter barrel. Any large mold not made of a higher than normol durometer will sag without support when stood on end..just be aware of that.

For really big molds I use a high durometer rubber of 30 or above, I have a really hard platinum cure formula which is a 40 that I use when tolerances are important and I want to minimize shrinkage.

M

One of the pieces is approximately 9" x 13" x 5", and the other is approximately 18" x 6" x 3". My "usual" Silicone has a hardness of 25, which is fine on smaller pieces (plus I tend to make my molds with THICK walls), so deformation isn't an issue. On THESE pieces, though, i'm afraid that the hydrostatic pressure of the resin on the inside of the molds may cause deformation, as you mentioned. I think I'll go with thinner than normal (for me) walls on the molds and a good fiberglass mother mold to prevent things from getting wonky. It'll certainly be cheaper that way! :thumbsup

 

[foxbatkllr]

I've bought resin from them in the past and forgot that they sell Silicone, too! :wacko :lol

Their resin works well. Not wild about how fast it kicks, but with my small molds, it's workable. On something large, their resin would be scary to work with. :eek I'll look into their Silicones, though.

He is a local guy (to me) and real helpful. If you have questions about your particular application, he's always willing to help out on the phone.