Some info on silicone molds please

[Ken Massingale]

I'm getting back into turning after a long hiatus.
I'm making a 5 blank mold with the Alumilite Amazing Mold Rubber. (not sure if this is silicone or not)

I plan on making the walls 3/4" thick and the divider between blanks 1/2".

I have a pressure pot coming and need to know if this mold will be strong enough without re enforcing the perimeter walls.
Also does the 'rubber' mold need to be pressurized before using it?

Thanks for any help

ken

 

[EPCTX]

According to Zac Higgins you do need to pressurize the rubber before pouring. He's has a great video on what you're looking to do https://www.youtube.com/watch?v=o5kgu78qY8g&t=381s

Hope it helps!

 

[bmachin]

According to Zac Higgins you do need to pressurize the rubber before pouring. He's has a great video on what you're looking to do https://www.youtube.com/watch?v=o5kgu78qY8g&t=381s

Hope it helps!

Zac DOES NOT uses pressure on the silicone. He does use his pressure pot as a vacuum chamber to degas the silicone prior to pouring. He explains this in his response to the first comment under the video.

Also, the material that he used was Alumilite High Strength 1. Can't comment on how that would compare to Amazing Mold Rubber for this purpose. Might be worth a call to Alumilite.

He also provides this link:

https://www.youtube.com/playlistlist=PL6q0fd3ileWLwTQ6pOUb8isS4BYLjkNhH

Just a good source on mold making--nothing to do with penturning.

Bill

 

[EPCTX]

I stand corrected. You are correct, he applies vacuum before pouring. My mistake.

 

[Ken Massingale]

Thanks guys, I appreciate your replies.

 

[vtgaryw]

I'm getting back into turning after a long hiatus.
I'm making a 5 blank mold with the Alumilite Amazing Mold Rubber. (not sure if this is silicone or not)

I plan on making the walls 3/4" thick and the divider between blanks 1/2".

I have a pressure pot coming and need to know if this mold will be strong enough without re enforcing the perimeter walls.
Also does the 'rubber' mold need to be pressurized before using it?

Thanks for any help

ken

As far as this portion of your question - I'd say yes, reinforce the perimeter walls. I tried a few without doing that and I ruined several blanks.

-gary

 

[bmachin]

To give you some sort of idea on wall thickness take a look here:

https://ptownsubbie.com/collections/casting-molds

I don't know what silicon formulation is being used here, but the walls are not particularly thick and I'm pretty sure that they aren't reinforced in any way.

Just for what it's worth,

Bill

 

[leehljp]

Welcome back Ken. Been a long 10 years since you were here last, I think.

Welcome back!