Permatex Rtv Silicone Gasket Maker

[MG50]

Hello everyone

I have been researching on the site for sometime. Great site by the way. I have made a few POP molds and wanted to make a RTV mold. I have not found any 2 part RTV in town I have found Permatex RTV silicone gasket maker in a good quantity come in caulk gun style or bucket. My question is has anybody use this on a mold i was wondering if i will run into cure problems being its a one part silicone. Any info is greatly appreciated. This is quickly becoming addicting along with my rod building.

Thanks

MG

[Smallie]

Hello everyone

I have been researching on the site for sometime. Great site by the way. I have made a few POP molds and wanted to make a RTV mold. I have not found any 2 part RTV in town I have found Permatex RTV silicone gasket maker in a good quantity come in caulk gun style or bucket. My question is has anybody use this on a mold i was wondering if i will run into cure problems being its a one part silicone. Any info is greatly appreciated. This is quickly becoming addicting along with my rod building.

Thanks

MG

Do a search on silicone mold making. There was an extensive thread about using the Walmart Mainstay line of 100% silicone mixed with a little water to create inexpensive molds.

[MG50]

Do a search on silicone mold making. There was an extensive thread about using the Walmart Mainstay line of 100% silicone mixed with a little water to create inexpensive molds.

Thanks for the reply. I found the post in a search unfortunately the wal mart here doesn't stock the mainstay silicon. Thats when i found the permatex brand.

[Piscivorous Pike]

Thanks for the reply. I found the post in a search unfortunately the wal mart here doesn't stock the mainstay silicon. Thats when i found the permatex brand.

If the permatex smells like vingar, that is the acetic acid element to the mix, it is the kind of silicone that cured by humidity and will cure with the addition of water. However, if it cures with water is no guarantee it will work for a mold. We found that the Wal-Mart clear and white although the same brand behaved differently, the clear was difficult to use and keep bubbles out and the white was smooth and pastey.

The problem is the thicker it is when you mix in water you mix in air. Usually I would use my seal a meal and seal up a qunatity of the RTV in a bag, before sealing I poure water in and then out and sealed it removing excess air from the bag. This was enough water adhering to the mix to stimulate a 20 minute set time. I kneaded the closed sealed bag with the moisture in it untill mixed, cut a corner and squeezed it out of the bag. That works very well- BTW.

Two part RTV in Shore 15-30 hardness pours like syrup or honey and therefore is easier to use to get the air out. Do a search on line for RTV. WE use many vendors, a favorite for TU is Smooth-on, others are Greer and so on. It runs about $30 a quart (2.2 lbs) or 85- 165 a gallon. I buy by the gallon, a C-note, but then again it is a hobby, how much do you spend on fun and enjyoyement, that is the measure for me, so I buy the real stuff to be serious and make do with the other stuff just to learn and have fun with it.

Recently I used the white Wal-mart RTV and made sheets of it it cut into hook slots to put in both pop and RTV molds. I mixed it with water and put in on a piece of glass. The glass had spacers on 4 corners the thickness I needed the sheet. I pressed another piece of glass on top and fltattened it out. (both glass were grease with vasolne). In 20 minutes I had a sheet of RTV. The hook slot material was cut from it, the part that extends into the mold RTV or POP was filled with holds from a paper punch to grip the material better.

What I am saying , try the permatex, a little bit and see how handles.

[Husky]

Thanks for the reply. I found the post in a search unfortunately the wal mart here doesn't stock the mainstay silicon. Thats when i found the permatex brand.

Did you go to the paint section? That's where I find mine. Ace Hardware stores brand will also work.