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ODD RESINS


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Frank, when you say, "it popped in the pot," do you mean you were curing the rubber under pressure to reduce air bubbles? Pressure-curing works (I did it for a couple of years before I could afford a vacuum pump), but the big drawback is that the pressure has to remain fairly constant during the whole curing cycle. If the rubber is halfway cured, the air bubbles that are crushed by the air pressure will expand in the soft rubber and ruin the mold. Mold Star 30 cures in about 7-8 hours, which is pretty quick. Did your pressure fall off from 35-40lbs during that period?

I'm not a huge fan of the Mold Star rubbers, even though I have been pouring molds with them all weekend. A good compromise between price and performance, but I wish they had more of the performance advantages of the old-fashioned Smooth-Sil platinum-cured rubber.

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Frank, when you say, "it popped in the pot," do you mean you were curing the rubber under pressure to reduce air bubbles? Pressure-curing works (I did it for a couple of years before I could afford a vacuum pump), but the big drawback is that the pressure has to remain fairly constant during the whole curing cycle. If the rubber is halfway cured, the air bubbles that are crushed by the air pressure will expand in the soft rubber and ruin the mold. Mold Star 30 cures in about 7-8 hours, which is pretty quick. Did your pressure fall off from 35-40lbs during that period?

I'm not a huge fan of the Mold Star rubbers, even though I have been pouring molds with them all weekend. A good compromise between price and performance, but I wish they had more of the performance advantages of the old-fashioned Smooth-Sil platinum-cured rubber.

the seal blew on the lid after 20 minutes, it was around 45lbs before i shut the valve off, i love mold star aside from the "it doesnt work well with tires" factor its a great compound for the price Edited by Lownslow
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Yea thats the big downside to platinum when molding rubber tires as masters, I get through it by painting the tire with primer or a clear.

I made new seals for my harbor freight pot with urethane rubber, so much better! between that and ball valves before and after the regulater I get constant pressure.

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i like the tire it looks great under most muscle cars heres the other mickey thompson im casting soon i all of a sudden want to build a street freak car and these are the best tires for it.

Sxe6u.jpg

if you cast this tire in hard resin so you could remove the writing on the sidewall then cast that version, it might interest some of circle track racers that might want to change the brand of tire for their use.

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Here are some tires I made using the Polytek Flex 50. A very nice product indeed. Here is the mold, not much to say about it except the cured tires put me in a sweat wrestling them out of their pockets. Thanks for the tip, ryan.

Greg

post-8648-0-34433000-1331531034_thumb.jp

post-8648-0-77329600-1331531096_thumb.jp

post-8648-0-94620500-1331531160_thumb.jp

Edited by Greg Wann
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Casey, compare your MRC M/Ts to the real ones and you'll see why they're not the best choice. The various words on the MRC sidewall are placed so haphazardly, it almost looks random. That might be OK if you don't paint the letters, but most guys who ran performance tires wanted the white letters showing.

That and they're awfully chunky-looking, at least to my eye. Best thing about those MRC hop up sets are the wheels... and those ever-useful adapters. B)

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Greg thats a funky mold. Can you share how you made it that way? I dont see any mold lines or pour/vent holes? Looks like you made a mold of the inside of the tire and then a mold of the entire tire encased in silicone? Curious to hear how you did it. Thanks.

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Greg thats a funky mold. Can you share how you made it that way? I dont see any mold lines or pour/vent holes? Looks like you made a mold of the inside of the tire and then a mold of the entire tire encased in silicone? Curious to hear how you did it. Thanks.

seen that mold before but for hollow tires i plan on doing one soon
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Greg thats a funky mold. Can you share how you made it that way? I dont see any mold lines or pour/vent holes? Looks like you made a mold of the inside of the tire and then a mold of the entire tire encased in silicone? Curious to hear how you did it. Thanks.

http://smcbofphx.pro...lay&thread=1297

Take the above link over to a forum that I show a lot of my casting work on. You will want to go to page two for the tire mold making. Most of page one are pictures of a Mercedes W196 Race car being taken apart. The mold I make is pretty simple and straight forward. I would suggest that you buy some of the Kleen Klay I use to clay up parts. The best deal for that is from Allumilite. Kleen Klay is to Resin casting as The Force is to Star Wars!! "LUKE, USE THE CLAY, LUKE"!

I do pretty much Encapsulate the entire tire in silicone. This mold will make some great tires when I have good resin to work with. As you will see when you go over to my light side of casting that when they put an expiration date on a can the stuff knows when to go bad!! YUP! These guys have expiration dates down to a science too. LOL The one thing about my mold is that the tires are not easy to remove. Be prepared for some excercise. Some of you guys making tires are just trying way too hard.

So....Check out my work and cruise around our forum. You can see and join for free. We are the guys that bring the Desert Scale Classic Model Car contest to life at the good Ol" Postal Hall every year and it's coming up in April in the Phoenix, AZ area. I'm sure Danno will post a fler soon. Enjoy and have fun. It's not just a forum to waste time at. Hopefully you will learn something about resin casting. Well......It's my take on the subject.

Greg Wann

AKA Shartin Looms

Edited by Greg Wann
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Greg, I've been experimenting with resin for about 2 years now and have done pretty well with it but tires have been hit or miss with me. Thanks for sharing that link. Very interesting stuff in there.

And not to hijack Franks thread, your stuff looks really nice too. Tires are looking good. Very informative post on so many levels. Thanks guys.

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OOPS! I too apologize for seemingly hijacking this thread. I am certainly not here to try to outdo anybody about this. I have been posting my resin work for some time now on our forum. Jeff Watlington the Time Machine Bandit guy was pretty helpful but a lot of what I show is what I dreamed up on my own. If I had a big Ego, I would say it was top secret and I would not post anything.

Greg

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I got my set of muscle car tires from Frank.

They were cast in the tan resin, and they are really good. no air bubbles whatsoever

A little cleanup, sanded off the pour stubs, cleaned up the relese agent, and voila, ready for primer and paint

good stuff :)

Cheers, Ian

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I got my set of muscle car tires from Frank.

They were cast in the tan resin, and they are really good. no air bubbles whatsoever

A little cleanup, sanded off the pour stubs, cleaned up the relese agent, and voila, ready for primer and paint

good stuff :)

Cheers, Ian

glad you liked them i cant wait to cast them in rubber B)

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