Local Mold Making Material

[joelhains]

Where can you buy mold making silicone or some kind of resin for making  2 piece soft plastic molds? I have tried the POP molds and the ones I did get to work didn't pick up as much detail as I would have liked. I have designed some swim baits and have master of them but don't want to have to ship the mold making material if there is something available locally. Does wal-mart, lowes or home depot carry anything that will work for this.

[bflp]

Hobby Lobby carries the Alumilite RTV mold making silicone. Use a 40% off coupon because it is a bit pricey.

[joelhains]

I am hoping to come up with a cheaper option to Alumilite. I am prototyping swimbaits other types of soft plastic baits and doing a lot of testing. I will be making several molds of lures before I am satisfied with the design. Even with 40% off Alumilite can get expensive. I seem to remember seeing somewhere that you could mix silicone chalking and something like paint thinners or acetone (I can't remember what it was) which would give it a thinner consistantcy which allows it to flow better and pick up more detail. I was hoping to find something along those lines.

[Roger Linnell]

I am hoping to come up with a cheaper option to Alumilite. I am prototyping swimbaits other types of soft plastic baits and doing a lot of testing. I will be making several molds of lures before I am satisfied with the design. Even with 40% off Alumilite can get expensive. I seem to remember seeing somewhere that you could mix silicone chalking and something like paint thinners or acetone (I can't remember what it was) which would give it a thinner consistantcy which allows it to flow better and pick up more detail. I was hoping to find something along those lines.

I tried some of those recipes, couldn't get happy with any. Alumilite is definitely the way to go as far as silicone. I make my plaster molds with Tuff Stone, great detail and super strong.

Edited July 14, 2013 by Roger Linnell

[EdL]

Try going to the top of 'Soft Plastics' page and do a search for 'Silicon Mold'  There will be a bunch of posts listed. One titles something like RTV mold for $1.50 has pages of discussion about using tubes of silicon sealers/adhesives.  One of the best tools for finding info is the search function (and its free and fast).  There's s-o-o-o much information on TU if you just look for it.  Almost too much but there's a lot of things tried and discussed. 

[rixon529]

I believe one of the "tricks" mentioned a few years ago was to get the $2/tube silicone caulking from Walmart or the like.  Squirt it out of the tube and let it cure, then cut it up into small chunks and use it as a filler for the "good" silicone used for mold making.  It will considerably reduce the quantity needed and thereby save you some of the expense.

 

Rick

SE CT

Edited July 14, 2013 by rixon529

[Slammingjack]

I have done the silicone mold. Not the 2 part mold, just the open pour. A few things about it: One: use 100% silicone. I get mine from Ace Hardware. Around 5-6 bucks a tube.Two: What you add to it is water. Not very much. I use 1/4 tsp to a full tube. It will only takes so much water, the rest will not mix in. (pour that left over water out before you mold). Make sure all the silicone your going to use has water in it. ( or you end up with a mess) The water makes it setup in like an hour( I give it two just to be sure) Three: your model must be hard( I use baked clay) Your model must also be sealed( I use mod podge. I got it before I learned there was better stuff).Four: Mix it in a plastic bowl. I get mine from the dollar store. ( well for a dollar) Once  the silicone sets up it will peel right out. So you can use it again. I have used white and clear. White makes a better looking mold. But clear it easier to tell if all has water in it ,because it turns opaque. You have to make a frame out of something. Need four sides and a top and bottom. I use wood because that's what I had. Don't glue it together, just use clamps. ( you have to pull the wood apart. Easier if not glued) Fill the frame all the way to it's even with the top. Push you model down from the top until it's just above the edge. Then use the top to push it down the rest of the way. Make sure the top is setting on the edge of the sides. This will push the excess out of mold and leave you a nice flat top on the mold. This will give you a very shiny bait. The detail is very good. Will  even pick  up the paint brush marks in the Mod podge. If your model has very thin or small parts, this may not be the way to go. Easy to break off in the mold. If you end up with bad places in the mold(voids), just mix some more silicone and water.Fill it in ( I use a q-tip dipped in water)and put the model back in. let it set up again. This is why I have not tried two part molds. Because the silicone will bond to the point where you can't tell where it was repaired. One last note if you do a swim bait with a paddle tail and the tail is 90 degrees all fine and good. If it's 45 degrees you must put the tail in at a angle. Then push down.

[joelhains]

Thanks very much Slammingjack! That's exactly what I need to know. I will give this a try!!

[Slammingjack]

Your welcome. One more thing adding water makes the silicone smell a lot stronger. Need to wear a vapor mask or respirator.

[agarrett]

I am hoping to come up with a cheaper option to Alumilite. I am prototyping swimbaits other types of soft plastic baits and doing a lot of testing. I will be making several molds of lures before I am satisfied with the design. Even with 40% off Alumilite can get expensive. I seem to remember seeing somewhere that you could mix silicone chalking and something like paint thinners or acetone (I can't remember what it was) which would give it a thinner consistantcy which allows it to flow better and pick up more detail. I was hoping to find something along those lines.

Hey, when prototyping, it does get pricey using alumilite or even the tube method. I use a product called composimold. You can google it and I have mentioned it before on here. It isn't the most durable but here is the benefit to it. It acts almost exactly like silicone, good flex but not too much, and good durability for medium size runs. The best part is that it is reusable. All you do is heat it up in the microwave until it turns to liquid and then pour it in your mold. It hardens as it cools. And doesn't take that long. Once you get the lure the way you want it you can make a master out of something else more expensive and durable.

[Travis]

I would honestly revisit the POP.  When done correctly you can easily get rather impressive detail pick up with POP.  Depending on the detail it may not be important with regards to prototyping.