HickoryHollow Posted November 17, 2013 Report Share Posted November 17, 2013 Has anybody used silicone mold making products? There must be a down side, do they not hold up long or what? http://www.alumilite.com/ProdDetail.cfm?Category=Silicone Amazing Mold Rubber Tim Quote Link to comment Share on other sites More sharing options...
Travis Posted November 18, 2013 Report Share Posted November 18, 2013 Commonly used to make molds. They hold up for a long time but most gravitate towards aluminum molds as they don't want to make them or don't have the skill to make a decent mold (or master). Quote Link to comment Share on other sites More sharing options...
gone2long Posted November 18, 2013 Report Share Posted November 18, 2013 Get a few molds from Lurecraft they are silicone and give them a test run, they work great last long and are dirt cheap in the world of 1 piece molds. Quote Link to comment Share on other sites More sharing options...
agarrett Posted November 19, 2013 Report Share Posted November 19, 2013 I make silicone molds all the time. There are a million different silicones out there. If you want something that is going to hold up, you really should get something that has a good density and high tear strength. The alumilite one that is sold at my local Hobby Lobby is not that great. It has a good density but it also "cracks" and tears when stretched a bit. This will work great and I have been using the same mold for two years but I'm not sure how long it will hold up. The good thing about making silicone molds is that once you make one, you can make a hundred of the same one. When I make a mold out of silicone and I get it the way that I want it, I will make a master out of casting resin so that I can make more silicone molds. Here's a tip that I dont tell too many people (at least until now). I take a peice of plexiglass and put whatever object I am trying to mold on it. I then build a box out of legos (no bottom on it) and set it around the object to mold. make sure you leave enough space around the object 1/2" to 1" should be plenty. Then I use a hot glue gun and run a bead all the way around the base of the lego box. you can also use duct tape or silicone but the corners are hard to seal with duct tape and the silicone will take a little while to dry. Once the box is secured, I pour my silicone into the box to the desired thickness. I usually pour in one corner and let the silicone spread itself over the object. (not sure why but I read it somewhere so that's what I do) Then I tap the box gently to get any air bubbles to rise to the top. Let the silicone fully set up and then you can remove from your legos. Here's the complicated part. If you are making a two part mold, you will need to add something inside the box so that when you mold the second half, the two sides will always line up correctly. For this I like using small acorn nuts. All you do is add a small dab of hot glue to the bottom of the nut and glue several of them to the plexi glass. You will also need to create a spout for pouring (not needed for one part molds). Modeling clay in the shape of a half-cone is an easy solution. **make sure it doesn't contain sulfer because the silicone will not cure around it** Once it is cured, remove the mold from the box and take out the nuts and clay. This is why I like legos- Flip the silicone over and build the same size box around it and add the clay pour spout so that it is a full cone . Now you can pour the second half of the mold the same as the first. I use cooking spray to lubricate the first half so that the second half doesn't stick to it. Just use a very thin layer and wipe off excess. To make duplicates of your mold/mold halves, simply make a box around each half and pour casting resin over it so that it fills the cavity and the box. I usually try to go about 1/2 inch above the silicone mold. **I would use a good mold release to help the resin to not stick to the legos, again cooking spray works find** Once that hardens completely, break apart the box to remove it. Now you have your master and can make all the molds you want by putting a box around it and pouring in your silicone. this is way more than you asked for but once you have the master made, you can make as many as you want and the life of the mold won't matter as much. They do last for a long time though. There are also some threads on here about using GE brand silicone in the tubes and adding a tiny amount of water to it to help it cure correctly. Supposedly it has the same result as the alumilite types. I have not tested it yet but it could be a cheap alternative. For practicing with making molds or making molds for small runs, there is another type that you heat up in the microwave and then it hardens when cooled. It's called composimold and is relatively cheap. you can google it. This is primarily what I use to make my masters because you can reuse it just by putting it back in the microwave so it saves tons of money. Final note, the amazing molding putty/rubber is only good for certain applications. It is a putty so you have to work it around the object you are molding and unless that object is very rigid, you will lose a lot of detail. I do have several tubes of it at home, Hobby Lobby sells it and it comes in a box with two tubes- one yellow and one white and you just mix them together to an even color and then press it around the object. You do lose details with it though and it can take quite a bit to finally get a good mold. 1 Quote Link to comment Share on other sites More sharing options...
agarrett Posted November 19, 2013 Report Share Posted November 19, 2013 BTW HickoryHollow, I only live about an hour from you just east of Akron. I'm not a pro at this but I have definitely spent my share learning. Quote Link to comment Share on other sites More sharing options...
HickoryHollow Posted November 19, 2013 Author Report Share Posted November 19, 2013 agarrett, Wow, your post was great, and very, very helpful! I made my first mold from the amazing rubber last night. It didn't come out too bad, but there is room for improvement. I will go post pictures in the gallery of the process and my results. Please feel free to criticize, that is how I will learn! Oh, and I already learned not to drip hot plastic on my fingers!! I will remember that one! Thanks, Tim Quote Link to comment Share on other sites More sharing options...
HickoryHollow Posted November 19, 2013 Author Report Share Posted November 19, 2013 Oh, one more question. If you went to the gallery, you saw I am pouring frogs. Also, as you guys probably already know, they float, but barely. I have read about using micro balloons in the plastic to make it more buoyant. We used to use micro balloons to thicken epoxy resin when I used to build hovercrafts. If it thickens soft plastic the same way, it would be harder to pour. Are there any alternatives to make Mr. Frog stay on top of the water? Thanks, Tim Quote Link to comment Share on other sites More sharing options...
Travis Posted November 19, 2013 Report Share Posted November 19, 2013 I mainly have used Smooth On RTV in the past and use the techniques mentioned above. I don't like RTV for two piece as they insulate too well and takes a long time to demold. Mold I made for cranks years ago but you can see some of the details mentioned above. I use worm weights typically for the keys to help align the mold along with BBs for cranks and do similar for soft plastic two sided but to less extent (picture one) Acrylic is generally what I use when I carve a master and pre drill a hole (countersink the screw head in the acrylic) and just screw it through into the master. For plastic baits I just lightly coat the side that sits on the acrylic with vasoline and it sticks in place just fine. As mentioned legos are the usual method used as they are quick and easy to resize the box. I also often just use the backside of aluminum molds to make the walls. Mold release helps for sure and I have typically used Mann's Ease Release when needed. Unless the master has lots of undercuts just ends up being cheaper and almost as good detail if you take your time and just use POP or rock puddy. A lot of this is covered in the crank bait section under foamies 8 to 9 years ago or longer perhaps. Of course you can find a lot of if in the soft bait portion also just have to weed through a lot of information. Quote Link to comment Share on other sites More sharing options...
HickoryHollow Posted November 19, 2013 Author Report Share Posted November 19, 2013 Thanks Travis, Great information, and those are some really nice molds you made! Quote Link to comment Share on other sites More sharing options...
Slammingjack Posted November 22, 2013 Report Share Posted November 22, 2013 Here some more info. http://www.tackleunderground.com/community/index.php?/topic/26618-local-mold-making-material/?hl=slammingjack#entry203760 hope that works lol Quote Link to comment Share on other sites More sharing options...
agarrett Posted November 24, 2013 Report Share Posted November 24, 2013 Hey Travis, what kind of plastic are you using to pour your crankbaits? Quote Link to comment Share on other sites More sharing options...
Travis Posted November 24, 2013 Report Share Posted November 24, 2013 Not using plastic for cranks. I have just stuck with the 2 part polyurethane foam in 16 lb density. Quote Link to comment Share on other sites More sharing options...
EdL Posted November 25, 2013 Report Share Posted November 25, 2013 Agarrett - nice write up. Just what brand and type of silicone are you using to make the mold? Quote Link to comment Share on other sites More sharing options...
agarrett Posted November 26, 2013 Report Share Posted November 26, 2013 I have used: Smooth-On Mold Star 15- turquoise color, fairly soft, high tear strength very durable Alumilite Quick Set RTV silicone- Off white/ beige color, fairly hard, low tear strength. Alumilite High Strength 3- Pink color, medium softness, good tear strength, very durable. All three have their ups and downs but I would recommend either the Alumilite HS 3 or the Smooth-On Mold Star 30 (it's the next one up from the 15 and has a higher hardness rating). For open pours, I prefer the Alumilite Quick Set because it's harder doesn't flex when trying to move them after filling. I mostly make hard plastic or POP molds for open pours now though. I will make the master out of silicone and then pour resin or POP on top of it for the mold. All of them have been very easy to work with and are a 50/50 mix ratio. I just eyeball it. I have some pics at home that I can share later of some of the molds I've made. Quote Link to comment Share on other sites More sharing options...
EdL Posted December 1, 2013 Report Share Posted December 1, 2013 Been away a few days - belated thanks to a garrett for sharing what he uses and his experiences. Quote Link to comment Share on other sites More sharing options...
Travis Posted December 1, 2013 Report Share Posted December 1, 2013 (edited) When it comes to mold making it really comes down to how much one wants to spend on the mold but more importantly it comes down to the skill set you learn. You can get very good results from about any mold medium it just takes some practice and a little patience. I think guys really put way to much effort into finding the "perfect' material instead of really learning. Most of the molds I have made have been Durham's' rock puddy, POP, RTV silicone (Mold Max 30), and Bondo body filler. I have made some with various other mediums but usually stick with the the prior based on three of the four are on the shelf less than a mile from the house. Some are slightly easier to use than others but for most nothing they can't figure out on the spot. Edited December 1, 2013 by Travis Quote Link to comment Share on other sites More sharing options...
JJK Posted December 24, 2013 Report Share Posted December 24, 2013 hey guys has anyone here ever used m-f rtv silicone if so what was the out come just got some a few days ago for the first time i have always used alumilite in the past and been pleased but the m-f did not give the sheen in the mold that i was use to Quote Link to comment Share on other sites More sharing options...
