acklac7 Posted February 11, 2006 Report Share Posted February 11, 2006 Im going to be purchasing some RTV in the coming days and was wondering if anyone has some info on where to find cheaper RTV. My past two purchases have been from LC...But I just can't afford to spend $33.90 per 8oz kit...There has to be a cheaper option...right? Someone else noted http://www.smooth-on.com, however they have a plethora of different products/compounds..Not sure which one(s) to buy. Anyone else know of any suppliers that have cheap RTV (or some other flexible mold-casting compound)? Thanks! Quote Link to comment Share on other sites More sharing options...
bassnfool Posted February 12, 2006 Report Share Posted February 12, 2006 Go to www.micromark.com. They have a 1:1 mix silicone part number 82083, 32 ounces cost $31.75. I've been using it and it is excellent. Quote Link to comment Share on other sites More sharing options...
Predator Bass Baits Posted February 19, 2006 Report Share Posted February 19, 2006 Do you use a mold release as well that they sell ? Item # 82664 Quote Link to comment Share on other sites More sharing options...
bassnfool Posted February 19, 2006 Report Share Posted February 19, 2006 I use their Mold release "Mann 200" for rubber to silicone, silicone to silicone. Works fine. Quote Link to comment Share on other sites More sharing options...
Predator Bass Baits Posted February 19, 2006 Report Share Posted February 19, 2006 Thanks, I believe the item# above is the same. http://www.ares-server.com/Ares/Ares.asp?MerchantID=RET01229&Action=Catalog&Type=Product&ID=82664 Quote Link to comment Share on other sites More sharing options...
acklac7 Posted March 4, 2006 Author Report Share Posted March 4, 2006 Update: I received my RTV from M.M.....stuff is great..nearly identical to the stuff l.C. has....M.M. also carries alot of neat stuff for your average hobbyist...Great site! Thanks bassnfool! Quote Link to comment Share on other sites More sharing options...
bojon Posted March 4, 2006 Report Share Posted March 4, 2006 Micro Mark has a great small paint shaker.I put my small containers of dye in a snack size baggie,then let it shake it really good.The colors are more consitant drop by drop,and the batch of plastic does'nt vary as much. The only brand of RTV I have ever was from Micro Mark,and it has been flawless,so I can't compare to other brands.[/b] Quote Link to comment Share on other sites More sharing options...
dtrs5kprs Posted March 5, 2006 Report Share Posted March 5, 2006 I have used LC's RTV, the one from Barlow's, two different products from US Composites, and one other one (a 1:1 mix product that I do not care for). Just received my first RTV's from Smooth On this week, ordered 2, have 2 more on order. I have not yet used their RTV, but I have used Smooth On's 300 series plastic for making master/mother molds for several years now & it is excellent. Pending results with Smooth On, I would spend my $$$ on the RTV from LC. It works every time, excepting the occasional instance of DOH! on the part of yours truly. Will post results from Smooth On when I have some. Working on masters for a few new custom molds, and will be pouring RTV when those are complete. Quote Link to comment Share on other sites More sharing options...
acklac7 Posted March 5, 2006 Author Report Share Posted March 5, 2006 Im currently using the 1 to 1 stuff..Not sure if it is the same 1:1 you were using, but it works fine for me! How did you like US Composites product(s)? I'm in the market for some bulik RTV and came across there site...I believe I can get 10 gallons from them for about $450.00 w/shipping...How did there RTV hold up? would you purchase it again? Quote Link to comment Share on other sites More sharing options...
dtrs5kprs Posted March 5, 2006 Report Share Posted March 5, 2006 I found the US Comp 25 product to be a lot softer than the products I was used to. The next harder product (40 I believe) is probably a better choice for lead molding. Depends on what you are looking for I guess. I have had too many issues with bubbles and sticking to masters with the 1:1 product I have used. I did order some of Smooth On's 1:1 (920 without looking) and will give it a go. Quote Link to comment Share on other sites More sharing options...
acklac7 Posted March 5, 2006 Author Report Share Posted March 5, 2006 I found the US Comp 25 product to be a lot softer than the products I was used to. The next harder product (40 I believe) is probably a better choice for lead molding. Depends on what you are looking for I guess.I have had too many issues with bubbles and sticking to masters with the 1:1 product I have used. I did order some of Smooth On's 1:1 (920 without looking) and will give it a go. Thanks for the info...I will agree with you on the bubble factor of the 1:1 stuff...However for the price im willing to deal with it...for now. Once I begin mass production of my molds I may reconsider. Did you have any problems with bubbles with the US Comp RTV? Also any ideas on how long RTV should last? (# of pours) Is the longevity of RTV fairly the same? or do some brands last longer than others? Quote Link to comment Share on other sites More sharing options...
dtrs5kprs Posted March 6, 2006 Report Share Posted March 6, 2006 US Composites products were about the same as LC, with respect to bubbles. Really, all of this goop should be degassed, but some will work for countertop production. As for longevity...I have some RTV molds I made in 1997/98 (zippers & chunks) that have seen literally several thousand pours per cavity without issue. As some posts mention, the color of the mold may change & there may be some loss of flexibility with prolonged heating (meaning getting the mold hot and keeping it there, as when pouring several hundred of a given color) but with care should still yield a nice bait. Some of mine have become "sweaters" with age...sort of a greasy oil/water moisture that seeps out, esp as they cool. Has not affected the cavities or quality of pours so far. Obviously if moisture gets in a cavity you need to wipe it out. Quote Link to comment Share on other sites More sharing options...
acklac7 Posted March 6, 2006 Author Report Share Posted March 6, 2006 Thanks for your help! Quote Link to comment Share on other sites More sharing options...
jm Posted March 6, 2006 Report Share Posted March 6, 2006 <> have had too many issues with bubbles and sticking to masters with the 1:1 product I have used. I did order some of Smooth On's 1:1 (920 without looking) and will give it a go. << end clip>> Any RTV product will benefit greatly by being subjected to a heavy vacuum between mixing and pouring. The vacuum makes the small bubbles greatly expand and then break. Any that are too small to do this will be so small when the vacuum goes off that they will not matter. hope it helps. jm Quote Link to comment Share on other sites More sharing options...
acklac7 Posted March 7, 2006 Author Report Share Posted March 7, 2006 <> have had too many issues with bubbles and sticking to masters with the 1:1 product I have used. I did order some of Smooth On's 1:1 (920 without looking) and will give it a go. << end clip>> Any RTV product will benefit greatly by being subjected to a heavy vacuum between mixing and pouring. The vacuum makes the small bubbles greatly expand and then break. Any that are too small to do this will be so small when the vacuum goes off that they will not matter. hope it helps. jm Thanks for the tip!!! I have one of them foodsaver vaccum-sealers.. Would that do the trick if I put the mixed the rtv in a jar,placed it inside a bag then vaccum sealed the bag? Quote Link to comment Share on other sites More sharing options...
Kman Posted March 7, 2006 Report Share Posted March 7, 2006 Thanks for the tip!!! I have one of them foodsaver vaccum-sealers.. Would that do the trick if I put the mixed the rtv in a jar' date=' placed it inside a bag then vacuum sealed the bag?[/quote'] If you already have the foodsaver pump, get one of these vacuum containers. Target lists them on their website for $10. Should make the degassing process a snap. There?s also a hand pump out there for another ten bucks or so that will pull a pretty good vacuum. Kurt Quote Link to comment Share on other sites More sharing options...
jm Posted March 7, 2006 Report Share Posted March 7, 2006 Thanks for the tip!!! I have one of them foodsaver vaccum-sealers.. Would that do the trick if I put the mixed the rtv in a jar,placed it inside a bag then vaccum sealed the bag? I doubt it. The spec calls for 29 inches (of mercury) of vacuum. I've found that the vacuum from a refrigeration compressor, deep enough to make water boil at room temperature, is just barely enough. It does work, though. A small evacuation pump specifically made for refrigeration should work very well. The difference between a real vacuum pump and a refrigeration compressor is that a vacuum pump's valves are mechanically driven, and need no air to operate. A refrigeration compressor's valves are reed valves that need some air or freon to make them open, thus limiting how deep the vacuum can get. For the very serious, they make vacuum pumps for roughing a high vacuum operation (like semiconductor manufacturing). If the pump has a gas bypass system, it can be used for drying, and actually handle large amounts of water vapor. A small one of these is many hundreds of dollars. I lucked out, and found a one horse unit in working order in a salvage yard, and bought it as a junk motor. It would have cost me almost $3,000 to buy it new. I usually mix up either RTV or Ultracal in a paper container, then put the whole container into a glass vacuum jar (a wide mouth fruit jar works for small amounts) so I can watch the action. Be sure to give it lots of room to expand, or it will get into your vacuum pump and cause real trouble. hope it helps jm Quote Link to comment Share on other sites More sharing options...
Kman Posted March 8, 2006 Report Share Posted March 8, 2006 I doubt it. The spec calls for 29 inches (of mercury) of vacuum. I've found that the vacuum from a refrigeration compressor, deep enough to make water boil at room temperature, is just barely enough. It does work, though. Here's a hand pump. The manufacturer claims it pulls 28.9 inches. http://www.pump-n-seal.com/comparison.htm Quote Link to comment Share on other sites More sharing options...
jm Posted March 8, 2006 Report Share Posted March 8, 2006 Here's a hand pump. The manufacturer claims it pulls 28.9 inches Go for it. I was thinking of the 2-24 inch products. If it pulls the claimed vacuum, it'll help a whole bunch fer sure. jm Quote Link to comment Share on other sites More sharing options...
