Big Splash Posted July 9, 2003 Report Share Posted July 9, 2003 The soft plastics forum is ripe with good tips lately, so I would like to bring up the subject of mold making. I've checked he archives, and found alot of good info on several types of handmade molds for soft plastics. I'm interested in multi-cavity molds, for small production purposes. I'm also interested in making full round baits like the 'clamshell' one in Red's tutorial. I've made up some 'masters' from sculpey clay, and would like some info on the best way to get good molds from these. I'm new at the soft plastics game, and any help would be appreciated, thanks. Quote Link to comment Share on other sites More sharing options...
jrav Posted July 9, 2003 Report Share Posted July 9, 2003 Well, I'm about as green as the grass on mold making myself but have made several simple ones. One thing I can say about redg8r's silicone clam mold idea is to work fast. Make sure all masters are ready to go for the silicone really does set up fast. I thought mixing water in it was absurd and and would never work. It works incredibly well! Less than an hour to cure. BTW, if you ever get sick of the Sculpey softness, try Fimo. It's a nasty one to condition, but the detail possible with this firm clay is awesome. Same advice with the plaster if you chose to give it a go. It likes to "hump up" when something is pressed into it if it's to far along. Not sure if you have ever worked with plaster, if not you'll want to practice this a bit. jrav Quote Link to comment Share on other sites More sharing options...
redg8r Posted July 9, 2003 Report Share Posted July 9, 2003 Hi guys, Ive been spending more time lately focusing on soft plastics also. Mainly because its my favorite to fish & I always put em in the boat with SP's down here. I'm so addicted, I try my hand at everything, plugs, plastics, tying, leag casting, etc. I've found a few more tips that have helped me, I will be adding these tips to the tutorials section soon, but I'll go ahead & share what Ive been doing. Ive been fascinated by the durability & quick turnaround of silicone, it has a lifespan, unlike aluminum, but if taken care of will last long while. the best thing Ive done so far is save on costly RTV by "backing" my molds with the household variety of 100% silicone. What I do is pour just enough RTV to house the master, then add 100% silicone on top of the RTV (after cured) to give it more bulk. Another thing on multicavity molds, what I do is make one single mold from a master, then use it to pour resin in to get duplicates, then I mold all the duplicates for the multicavity mold. Ive also leaned toward 2 part molds, thier easier to use than the "clam mold" but if your using the 100% silicone, thats the bast way to go, because its really thick stuff. For 2 parts, using clay to bed the master works really well. The polymer clays are a pain unless theyre conditioned (kneaded) What I do is take equal parts of 2 different colors & knead them until the color change is uniform. then I start the process.........dental picks work well for sculpting. Ive got to give some credit to Jed (riverman) for helping introduce the 100% silicone trick to the community. We both watch a casting newsgroup & saw the same resource at the same time. looking for casting & molding tutorials on the web have helped me alot. Hopefully soon we can save ya a trip, by puttin them here. good luck with it guys. Quote Link to comment Share on other sites More sharing options...
Pop Posted July 12, 2003 Report Share Posted July 12, 2003 I should stop reading the plastics section of the board and stick to my jigs but I am just too fascinated. There is a swim bait that I like very much and would go nicely with a new jig mold I am purchasing. I only have one swim bait of this type and can't remember where I got it from. The swim bait is very soft (I'm sure hand poured) with great tail action, and I am visioning it swimming behind my jig looking just like a bait fish. I have never carved anything and don't think I would be anywhere good enough to carve the bait for a master. Can I use the one bait I have to make a mold? Keep in mind that the tail is very flexible and I don't know if it will stay straight if I pour over it. Also will I need to spray the bait with anything as a release agent? Can somebody walk me through the procedure slooooowly. Any help will be appreciated. Thanks, Pop Quote Link to comment Share on other sites More sharing options...
redg8r Posted July 12, 2003 Report Share Posted July 12, 2003 Hi Pop, The first question that comes to my mind is, are you intending to sell this swimbait? if so you might wanna find the maker & see whats advisable. As to molding a soft plastic bait, I'm sure its been done, but I havnt successfully done it yet. I had the same issues you mentioned,........ keeping it in place without deforming it. Quote Link to comment Share on other sites More sharing options...
kidlizard Posted July 13, 2003 Report Share Posted July 13, 2003 Well Guys, Looks like I might finally be able to help someone else for a change.....I mold original soft plastic baits all the time. Its not that bad, but a few tips can save you all the heartache I have been through to figure this out. I start with a small "FLAT" metal pan. I then add scotch double sided clear tape to the bottom. Then I put the bait in place making sure it has a firm grip with the tape. After that I vasoline the whole thing bait and all with the lightest coat possible. Now I use fiberglass resin (bondo works well for small quanities and can be found at wal-mart, but I get it by the gallon at the auto parts store) Mix the resin very thouroughly!! I even add a couple drops of worm dye right before I mix, and it makes it very visible when you are done mixing. Finally I pour the resin over the bait "SLOWLY", wait about 30 minutes while its still warm and pop it out. The plastic bait ussually comes out of the resin easily, but will be very soft and gooey due to the heat from the resin. The last tip is not to add too much catylist, because it will get too hot and melt the bait. Any of that make sense???? A little sanding and cleanup from the goo and your ready to pour a few baits. ( the finish is not as shiny as plaster, but I am working on that) Now for plaster. I basically do the same thing with the tape and vasoline. Then I mix the plaster thouroughly and bang it on the table to bring the bubbles to the top. (you have to work fast, sets up quickly) Then I pour just enough to cover the bait, and move it around with my finger to be sure the bait is covered all around the crevises and to remove air bubbles. Next fill the mold to the top with plaster, and lightly shake the mold to bring remaining bubbles to the top until it starts to set. Finally cure the mold in the microwave by heating for 3 minute intervals and setting it out until you see no more water vapor coming from the mold. (if you want to do any shaping of the cavity do it before you cure, its alot easier. I use small wood carving tools.) Now coat the mold with Devcon. (2 coats minimum) I always add a drop of food coloring to the devcon before i apply it because it gives you a visual reference so you wont miss any spots. No matter what the package says, wait a day between coats and another day before you pour. Just makes it all the stronger. Good luck and feel free to ask any questions if you think I can help you. John I forgot to mention that this is only for 1 part molds. I havent gotten brave enough to try the 2 part, I think I am going to leave that to Del. Quote Link to comment Share on other sites More sharing options...
Pop Posted July 14, 2003 Report Share Posted July 14, 2003 Thanks Kid, I was just wondering about what the others had to say about the weight of the material distorting the model? I have never worked with silicone, but; in my mind (and I'm leaving it to science when I die )silicone would be lighter than plaster or bondo? Have you tried any type of silicone? Thanks for your help, Pop Quote Link to comment Share on other sites More sharing options...
kidlizard Posted July 15, 2003 Report Share Posted July 15, 2003 No, I have not tried any type of silicone. I bought some to try G8Rs method for a clam shell, but I havent gotten brave enough to do it yet. The resin is very thin liquid when you pour it, and it has no effect on the lure as far as distorting it goes. Give it a try and let me know how it works for you. John Quote Link to comment Share on other sites More sharing options...
Big Splash Posted July 15, 2003 Author Report Share Posted July 15, 2003 Thanks for the informative replies, all. kidlizard's fiberglass resin single cavity mold sounds like good one to try, thanx kid. Sounds like plaster or RTV will be the way to go for two sided molds. Quote Link to comment Share on other sites More sharing options...
captjimbob Posted July 26, 2003 Report Share Posted July 26, 2003 I would like to throw my 2 cents in for the resin molds. I have made dozens of molds from resin and if you treat the molds right, they last a long time. I never tried the double sided tape trick, I just layed the bait in a Plano 3700, made sure it was flat and ready then mixed up a small batch of resin. I then glued the bait down with a few "strips" across, depending on the size of the bait, especially the head and tail. It also keeps the bait from floating up thru the resin. After to resin set, I could go back and finish the pour and the 3700 shapes the mold nicely. The marks from the "glue-down" barely show and no bass I've caught with my worms seemed to care. The only thing I would do differently is pour a thicker mold. Most of mine were rarely over 1/2-5/8" thick. After a lot of heating, they curl a little. If you want shiny worms, coat the mold with a little worm oil before you pour. Good luck! Quote Link to comment Share on other sites More sharing options...
