Mayberry_Customs Posted September 3, 2010 Report Share Posted September 3, 2010 Has anyone created a POP or Resin mold made for injection? If so could you explain your process of making this type of mold? I have been thinking about doing this, but just was wondering if anyone else had experience with it? Thanks, Andy Quote Link to comment Share on other sites More sharing options...
nova Posted September 3, 2010 Report Share Posted September 3, 2010 I've thought of it but the main problems are pressure and heat. You have to figure a way to hold the mold halves together firmly while injecting but not so tight that it breakes the mold(POP). Possibly two pieces of 1/2" plywood the size of the mold and clamps. Heat will warp the resin mold after a while which will allow the plastic to squirt out the sides possibly burning the operator. I used to make a few molds from resin but I didn't like the warping and I sure didn't like the smell transfer to the baits once the mold heated up. www.novalures.com Quote Link to comment Share on other sites More sharing options...
GDille Posted September 3, 2010 Report Share Posted September 3, 2010 I have used a welding clamp to hold halves of my POP injection molds. I made the molds to fill some larger orders, but they were trashed by the time I was done because of the heat/pressure. George Quote Link to comment Share on other sites More sharing options...
GB GONE Posted September 3, 2010 Report Share Posted September 3, 2010 I haven't made any resin...yet but I have several pop that I inject. All are single cavity but multiple cavity would be just as easy to make. Reinforce your pop with used dryer sheets in the mold. In all honesty, a pop injection mold is real easy. I rarely put vents in mine now as you can just hold them together with rubber bands and go. The imperfections and slight areas where the mold doesn't seal together allows air to escape and the mold to be injected easily. Don't push hard and be careful with your port. I have experimented with adding some sheet metal in the port area but have come back to Dave's (Vodkaman) suggestion of an rtv adapter. Made one that fits over the tip of the injector and it just cusions against the pop. Took a little work to get it just right as if you make it to big, it will push the mold apart. Check the way Mark (Poulson) made his pop molds with the hinge and backing. A very nice production pop mold could be made this way for pennies on the dollar. I can post up a bait or 2 tomorrow from one of the very intricate molds. Looks like it came from aluminum cnc mold. This one even makes me smile!!!! Jim Quote Link to comment Share on other sites More sharing options...
Vodkaman Posted September 3, 2010 Report Share Posted September 3, 2010 I can post up a bait or 2 tomorrow from one of the very intricate molds. Looks like it came from aluminum cnc mold. This one even makes me smile!!!! I would like to see the pics. I would also like to see pics of the mold and RTV adapter too. Always nice to see an idea come to life. Thanks Jim. Dave Quote Link to comment Share on other sites More sharing options...
GB GONE Posted September 3, 2010 Report Share Posted September 3, 2010 Will do Dave. Here is the link to Mark's idea and his directions! This is a recipe on how to do it right! 2 piece pop mold Jim Quote Link to comment Share on other sites More sharing options...
mark poulson Posted September 7, 2010 Report Share Posted September 7, 2010 Will do Dave. Here is the link to Mark's idea and his directions! This is a recipe on how to do it right! 2 piece pop mold Jim Jim, Thanks for the kind words. I've started using diluted D2T to coat my POP molds, and it works much better than carpenter's glue. I got the idea here. I mix the two parts of the D2T really well first, and then add denatured alcohol, in a 1/1 ratio, and mix it really well, too. The mixture is thin, and is absorbed into the POP without losing any of the details. Two coat, one right after the other, works for me. I still spray both halves with Pam before I pour, but the epoxy is so hard I probably don't have to. I just made a senko mold, and found out I'd made the vents too big when the plastic from my Cabela's Cajun Injector went out of the bottom almost as fast as I put it in the top! I would up with a bunch of hollow worms, with big air bubbles on the insides. I used bondo to fill in the oversized vents, and I'll pour another batch today to see how it works with the smaller vents I cut in the bondo. Quote Link to comment Share on other sites More sharing options...
GB GONE Posted September 9, 2010 Report Share Posted September 9, 2010 Just posted pics of the mold and resulting bait in gallery. With the injector, no vents were needed to fill even the tiny appendages and thin claws. I have hand poured this as well and get a decent bait after the mold heats up.... Gallery Jim Quote Link to comment Share on other sites More sharing options...
Vodkaman Posted September 9, 2010 Report Share Posted September 9, 2010 Nice pours, nothing wrong with those. Thanks for posting. Maybe more people might give it a try after seeing the quality that is attainable. Dave Quote Link to comment Share on other sites More sharing options...
GB GONE Posted September 9, 2010 Report Share Posted September 9, 2010 Maybe more people might give it a try after seeing the quality that is attainable. Dave I can lay the original bait out and the pop baits out in a line and you cannot pick out the bait from the commercial mold from the others. Granted there was extra care taken in making the mold however it was still made, sealed and poured in the same day. More molds could be made and this could be a production bait in less than 1 week. Jim Quote Link to comment Share on other sites More sharing options...
Mayberry_Customs Posted September 9, 2010 Author Report Share Posted September 9, 2010 That looks great ghost. How did you align the two halves when injecting?? Didn't see any kind of pin or anything in that mold. Just Curious. Looks like it can be done though! Quote Link to comment Share on other sites More sharing options...
GB GONE Posted September 9, 2010 Report Share Posted September 9, 2010 I have never messed with alignment pins and all that. The sides on the plastic containers I use as well as the bottoms are completely square. They line up perfect every time when you rubber band the molds together. Just put the halves together and pour or inject. Simple. I am working on a multi cavity worm mold now and will have that one operational soon. Same mold in aluminum is over $150. Think I will have around $2 in mine... Jim Quote Link to comment Share on other sites More sharing options...
Mayberry_Customs Posted September 9, 2010 Author Report Share Posted September 9, 2010 Oh i see..Would love to see some photos of that mold when finished, sounds awesome, i have to give this a try before to long! Really wanting to make a mold similar to the BPS Incredible Craw for jig trailers. Love that bait on finesse jigs. Quote Link to comment Share on other sites More sharing options...
GB GONE Posted September 10, 2010 Report Share Posted September 10, 2010 Oh i see..Would love to see some photos of that mold when finished, sounds awesome, i have to give this a try before to long! Really wanting to make a mold similar to the BPS Incredible Craw for jig trailers. Love that bait on finesse jigs. LOL!! I have some of those craws and thought that would be a good challenge as the bait itself is really small. I will see if I can squeeze one in today!!! Jim Quote Link to comment Share on other sites More sharing options...
mark poulson Posted September 10, 2010 Report Share Posted September 10, 2010 LOL!! I have some of those craws and thought that would be a good challenge as the bait itself is really small. I will see if I can squeeze one in today!!! Jim Jim, How did you keep the legs straight, or in line, when you put the masters into the POP? I've tried it with lizards, and they came out a mess. I was thinking I might have to glue them to a flat surface, and pour around them. And, while I've got your ear, do I need to use a release agent, like PAM, with an RTV mold? I just got a two cavity lizard mold from Lurecraft, and I am anxious to try to pour some, but I don't want to ruin it right out of the gate. Thanks in advance, Mark Quote Link to comment Share on other sites More sharing options...
GB GONE Posted September 10, 2010 Report Share Posted September 10, 2010 Mark: Tha baits I am going to duplicate, I will straighten for a couple days prior to the molding process. Getting the appendages straight in the pop is the toughest part of the molding process for sure. I just make sure I have a paperclip or something thin to adjust the bait after putting it into the pop. I mix my pop pretty thick so I know I can adjust the bait and it will stay where I move it. I was told by someone (can't remember who now so I can pass the credit on) that you can also get the bait real straight and freeze it a little prior to molding. Never tried that. On the rtv mold, just pour away. No release agent needed. Jim Quote Link to comment Share on other sites More sharing options...
mark poulson Posted September 10, 2010 Report Share Posted September 10, 2010 Thanks Jim. I'll do that. I was looking forward to using garlic PAM to add scent at the same time, but my local markets, both Vons and Ralphs, stopped carrying it. Drat! I had also thought about freezing the lizards, but getting them flat and in position first is the hardest part, plus the fact that the legs attach pretty high up on the body. If they were frozen solid, then I could add some modeling clay to fill any voids before I put them in the POP. But, assuming I can had pour this open lizard mold, I won't have to worry about making one out of POP. Mark Quote Link to comment Share on other sites More sharing options...
nova Posted September 10, 2010 Report Share Posted September 10, 2010 Mark: Tha baits I am going to duplicate, I will straighten for a couple days prior to the molding process. Getting the appendages straight in the pop is the toughest part of the molding process for sure. I just make sure I have a paperclip or something thin to adjust the bait after putting it into the pop. I mix my pop pretty thick so I know I can adjust the bait and it will stay where I move it. I was told by someone (can't remember who now so I can pass the credit on) that you can also get the bait real straight and freeze it a little prior to molding. Never tried that. On the rtv mold, just pour away. No release agent needed. Jim Jim; I'd be a little concerned about freezing the un-set POP. AS you know water expands when it freezes and then contracts when it thaws. To me, this can cause the pop to have some voids in it after it sets which will effect the way it pours as well as the lifespan of the mold. It could make the pop quite chaulky. I may also be wrong and it may be worth a try;lol. www.novalures.com Quote Link to comment Share on other sites More sharing options...
GB GONE Posted September 10, 2010 Report Share Posted September 10, 2010 Sorry.... I meant freezing the bait to make it stiff prior to molding, not freezing the mold. Jim Quote Link to comment Share on other sites More sharing options...
Vodkaman Posted September 10, 2010 Report Share Posted September 10, 2010 (edited) If I was to tackle a project like this, I would start with a block of soft clay. Using clay carving tools, remove clay and set the master into the clay. No need for accuracy or setting as low as the parting line, just deep enough that the soft plastic master can be safely retrieved after curing. Build the box and pour the PoP. Remove the master and fully dry the PoP mold half. Using a belt sander, I would then sand down to what I want as a parting line. Using a drill and a burr, create location bumps, as the mold face is now very flat and will not locate by itself. Re-build the box, replace the master and pour the second half. The pour hole/funnel can either be molded with clay or cut after completion with a drill and burr. If I was making an RTV mold of the soft plastic master, I would still make the PoP mold as described above, as far as belt sanding and creating the locator bumps. I would also add a clay pour hole (half). Replace the master and pour the RTV. Once cured, remove plaster (store for future molds), invert and pour the second half of the RTV two piece. I have made RTV molds of crank bodies using a similar technique to this in the past. More steps involved, but it makes for a very neat mold and a casting with a neat and minimal parting line. Dave ps, for injection, I would drill the pour hole after molding, starting small and increasing the drill size gradually. As the drill diameter gets larger, it may be better to turn the drill by hand, as the plaster cuts very easy. Would not want to destroy the mold at the last stage. Edited September 10, 2010 by Vodkaman Quote Link to comment Share on other sites More sharing options...
nova Posted September 10, 2010 Report Share Posted September 10, 2010 If I was to tackle a project like this, I would start with a block of soft clay. Using clay carving tools, remove clay and set the master into the clay. No need for accuracy or setting as low as the parting line, just deep enough that the soft plastic master can be safely retrieved after curing. Build the box and pour the PoP. Remove the master and fully dry the PoP mold half. Using a belt sander, I would then sand down to what I want as a parting line. Using a drill and a burr, create location bumps, as the mold face is now very flat and will not locate by itself. Re-build the box, replace the master and pour the second half. The pour hole/funnel can either be molded with clay or cut after completion with a drill and burr. If I was making an RTV mold of the soft plastic master, I would still make the PoP mold as described above, as far as belt sanding and creating the locator bumps. I would also add a clay pour hole (half). Replace the master and pour the RTV. Once cured, remove plaster (store for future molds), invert and pour the second half of the RTV two piece. I have made RTV molds of crank bodies using a similar technique to this in the past. More steps involved, but it makes for a very neat mold and a casting with a neat and minimal parting line. Dave ps, for injection, I would drill the pour hole after molding, starting small and increasing the drill size gradually. As the drill diameter gets larger, it may be better to turn the drill by hand, as the plaster cuts very easy. Would not want to destroy the mold at the last stage. Wow. Dave the engineer. lol Just teasing you Dave..........Nil www.novalures.com Quote Link to comment Share on other sites More sharing options...
GB GONE Posted September 10, 2010 Report Share Posted September 10, 2010 I guess if this was going to be a production mold, I might consider all that Dave but still doubtful. Pop is so forgiving and easy to work with that the perfection of the mold is just not required like that of an aluminum mold. Pop works best with the tiny imperfection as it allows the air to escape well without causing any flashing on the bait. In addition, I would highly recommend that you mold in the sprue, vents, runners, etc. Drilling them after the fact is very difficult as the drill will wander easily and you will ruin the mold after all your work. Use the sprue from another mold as your sprue. I use coffee straws/stirrers as vents many times as well. Toothpicks work well also. Just wiat to add the tiny vent material until the mold has set up for a minute or 2. Just finished 5 more molds of a thin paddle tail worm. Will be pouring them tonight after allowing them to dry today in the 95+ degree weather here in South Georgia! Jim Quote Link to comment Share on other sites More sharing options...
GB GONE Posted September 10, 2010 Report Share Posted September 10, 2010 PS AS far as containers to mold you baits in, consider this. Go get an old one-side Plano tackle box and take the lid off. Use the Plano for your molding box as you can use the spacers to increase or decrease your mold area easily. You can make many mold at one time as well. It is also very easy to clean and remove your pop mold out of. In addition, the groves in the sides (from the spacer slots) help line up your molds eliminating the alignment pegs. Jim Quote Link to comment Share on other sites More sharing options...
Vodkaman Posted September 10, 2010 Report Share Posted September 10, 2010 Wow. Dave the engineer. lol And proud of it Nil, proud of it. Thanks. Dave Quote Link to comment Share on other sites More sharing options...
