CNC Molds N Stuff Posted July 30, 2020 Report Share Posted July 30, 2020 (edited) Its some sort of foam or material that you put in the mold, boil it, and it swells to fill the mold. I've made a few cast resin molds for folks, but I don't understand this boiled foam process, what the material or media is, and the details of how its done. If I did I could make molds ideally suited to the process. Had a guy just buy my mini crank mold for this yesterday. If it works the way I am visualizing I don't see where it needs a casting sprue like a resin mold. Maybe just some vents. Edited July 30, 2020 by CNC Molds N Stuff Quote Link to comment Share on other sites More sharing options...
CNC Molds N Stuff Posted July 30, 2020 Author Report Share Posted July 30, 2020 P.S. It doesn't sound like a cast or poured urethane foam process either. Quote Link to comment Share on other sites More sharing options...
Anglinarcher Posted July 31, 2020 Report Share Posted July 31, 2020 Interesting idea. I am aware of no foam material that expands upon the addition by boiling, at least not a structural foam. It would have to have the two components (assuming it is binary) encapsulated in such a manner that upon heating it would mix and the reaction would start. Such mixing would be difficult. Upon some research, I am providing a link for your review. http://www.compositescentral.com/showthread.php?t=9307 Quote Link to comment Share on other sites More sharing options...
CNC Molds N Stuff Posted July 31, 2020 Author Report Share Posted July 31, 2020 (edited) in another group somebody sent me a picture of a catalog page from the Hagens catalog. It shows EPS pellets or expandable polystyrene pellets. I'm going to have to check it out. The fellow who sent me that picture said he bakes his in the oven. Edited July 31, 2020 by CNC Molds N Stuff 1 Quote Link to comment Share on other sites More sharing options...
Hillbilly voodoo Posted July 31, 2020 Report Share Posted July 31, 2020 I know nothing about this process but you have my curiosity please report back on what you find out Quote Link to comment Share on other sites More sharing options...
CNC Molds N Stuff Posted August 29, 2020 Author Report Share Posted August 29, 2020 (edited) Well I bought some expandable polystyrene beads from Hagen's. It was a better price than the guy on Ebay. I'll be trying to make some crankbaits using this process soon I hope. Probably start with this mold since I already have it. As you can see it works ok with resin (with a mold release) casting. I tried to find out from another guy who uses this process if: 1. It was better to use a mold with no sprue and just vents. 2. If the expanded material was strong/hard enough to form the bill (I was thinking supported bill design). I guess I'll have to make some more molds to try both of those things. Edited August 29, 2020 by CNC Molds N Stuff Quote Link to comment Share on other sites More sharing options...
woodieb8 Posted August 29, 2020 Report Share Posted August 29, 2020 whats the density of this foam in the picture? Quote Link to comment Share on other sites More sharing options...
CNC Molds N Stuff Posted August 29, 2020 Author Report Share Posted August 29, 2020 (edited) 1 hour ago, woodieb8 said: whats the density of this foam in the picture? Quote Probably start with this mold since I already have it. As you can see it works ok with resin (with a mold release) casting. That one is resin. Probably 1:1:1 microspheres:part-a:part-b. Could be 2:1:1. That's an old picture. Might be from the first time I poured that mold. 2:1:1 made it pretty buoyant with 1/16oz ballast. I found I liked it less buoyant and caught more fish and switched to 1:1:1 with 1/16 oz ballast with a low central CG. Edited August 29, 2020 by CNC Molds N Stuff Quote Link to comment Share on other sites More sharing options...
CNC Molds N Stuff Posted August 29, 2020 Author Report Share Posted August 29, 2020 As to the density of any foam I have absolutely no idea whatsever. Zero. Zip. Nada. I am NOT planning to use a cast catalyst kicked urethane foam with published data. I am planning to use Expandable Polystyrene Beads and I have found very very very very very very little information about them except for a couple guys who say they use them to make hard baits. Most of what I found were YouTube videos from manufacturers just hawking their wares without sharing anything except "look at our big machine", or guys working with EXPANDED polystyrene beads to make things. 1 Quote Link to comment Share on other sites More sharing options...
Vodkaman Posted August 30, 2020 Report Share Posted August 30, 2020 You can find the density very easily and quickly , Takes a couple of minutes. Dave Quote Link to comment Share on other sites More sharing options...
mark poulson Posted August 30, 2020 Report Share Posted August 30, 2020 11 minutes ago, Vodkaman said: You can find the density very easily and quickly , Takes a couple of minutes. Dave How do you do it? Quote Link to comment Share on other sites More sharing options...
Vodkaman Posted August 30, 2020 Report Share Posted August 30, 2020 Mark, I would normally direct you to the 'Archimedes dunk test' post, but let me outline the method as simply as possible here. Working in grams only: 1 - Weigh the item on a gram scale. write the number down. 2 - Place a (plastic cup) container of water, large enough to submerge the item, on the gram scale. 3 - Zero the scale by pressing the 'tare' button. 4 - submerge the item using a pin or long nose pliers. Write down the number. 5 - Using a calculator; divide 1st number by 2nd number. And that is it. Now you have the density in grams per centimeter cubed (g/cm3). Dave 1 Quote Link to comment Share on other sites More sharing options...
CNC Molds N Stuff Posted August 30, 2020 Author Report Share Posted August 30, 2020 1 hour ago, Vodkaman said: You can find the density very easily and quickly , Takes a couple of minutes. Dave After it's done. I passed general science in grade school too. LoL 1 Quote Link to comment Share on other sites More sharing options...
Vodkaman Posted August 30, 2020 Report Share Posted August 30, 2020 (edited) CNC - Well, don't tell me that you don't know the density of the material. Use your science grade school lessons. This is basic lure design. The density of the body material is important. Whether people get involved with the science or not, they know about density, they know the difference between balsa and cedar. All I am asking, and many others i suspect, is give us a number so that we can compare. This is not rocket science, just two numbers divided together! LOL! Dave Edited August 30, 2020 by Vodkaman 1 Quote Link to comment Share on other sites More sharing options...
CNC Molds N Stuff Posted August 30, 2020 Author Report Share Posted August 30, 2020 (edited) 59 minutes ago, Vodkaman said: CNC - Well, don't tell me that you don't know the density of the material. Use your science grade school lessons. This is basic lure design. The density of the body material is important. Whether people get involved with the science or not, they know about density, they know the difference between balsa and cedar. All I am asking, and many others i suspect, is give us a number so that we can compare. This is not rocket science, just two numbers divided together! LOL! Dave So smart guy, how do you weigh something you do not physically have? All of the clues are there. it should be apparent that I have not yet made at the time of the posting any baits using the expandable polystyrene pellets. Phrases like hope to make some soon might have been a clue if not a dead giveaway. I don't know if I'll be coming back on this thread to report any more on this process, but if anybody else is interested please drop me a p.m. and I'll be glad to tell you what I find out. Edited August 30, 2020 by CNC Molds N Stuff 1 Quote Link to comment Share on other sites More sharing options...
Travis Posted August 30, 2020 Report Share Posted August 30, 2020 My limited experience with EPS pellet... styrofoam. Density 11 to 33 kg/m³ Quote Link to comment Share on other sites More sharing options...
CNC Molds N Stuff Posted August 30, 2020 Author Report Share Posted August 30, 2020 7 minutes ago, Travis said: My limited experience with EPS pellet... styrofoam. Density 11 to 33 kg/m³ Given the process I expected a pretty wide range like that. Thanks. Quote Link to comment Share on other sites More sharing options...
Vodkaman Posted August 30, 2020 Report Share Posted August 30, 2020 CNC - You bought the pellets. The question of density was a reasonable question. But then you went on the attack with a rather facetious comment. Did you expect that I would let that go! Maybe you were just trying to be humorous. My left brained engineering mind doesn't cope so well with such. True, I could have analyzed the posts more and determined that you had not actually experimented with the material yet. But, it was a reasonable assumption that you had at least had a play with the material. Sure, let us reverse from this rather caustic discussion, I too have little more to say! Dave 1 Quote Link to comment Share on other sites More sharing options...
CNC Molds N Stuff Posted August 30, 2020 Author Report Share Posted August 30, 2020 (edited) There were multiple points where I mentioned "planning" and "going to." Your choice to use that as an argument was just that. A choice. There is no way your analytical left brained engineering mind missed that. It is highly doubtful that anybody else missed that. Even the post you chose to take offense to started with "when its done." Yet another indicator that it wasn't done yet, and your choice to be condescending was unwarranted. So to be clear. I bought some EPS pellets. THEY HAVE NOT ARRIVED YET. I HAVE NOT DONE ANYTHING WITH THEM YET. MY STATEMENTS ABOUT PLANNING TO AND GOING TO ARE FUTURE TENSE. THERE IS LITTLE AVAILABLE DATA ON THE PRODUCT IN GENERAL AND COMMON INFORMATION STORES THAT I COULD FIND. WHEN THE BEADS ARRIVE MORE DATA MIGHT BE AVAILABLE. AS LONG AS YOU CONTINUE ON THIS PATH IT BECOMES LESS AND LESS LIKELY I'LL SHARE IT HERE. Yes this is a caustic path. You chose it. If you can stop without one more parting shot I can. Edited August 30, 2020 by CNC Molds N Stuff Quote Link to comment Share on other sites More sharing options...
CNC Molds N Stuff Posted September 3, 2020 Author Report Share Posted September 3, 2020 Lesson 1. Do all of your work over a giant rimmed cookie sheet or baking sheet. The tiny little beads get every-freaking-where. Just opening the bucket was like pouring a bag of tiny marbles on the counter top. They are tiny. I may bake some just on a sheet of foil to see what their maximum expansion is. 1 Quote Link to comment Share on other sites More sharing options...
CNC Molds N Stuff Posted September 4, 2020 Author Report Share Posted September 4, 2020 Lesson 0. Read the destructions. It says work over cookie sheet. 2 Quote Link to comment Share on other sites More sharing options...
ravenlures Posted September 5, 2020 Report Share Posted September 5, 2020 So I gather that this is not for silicone molds, correct. Wayne Quote Link to comment Share on other sites More sharing options...
CNC Molds N Stuff Posted September 5, 2020 Author Report Share Posted September 5, 2020 Its seems not. The continuous temperature cycling would degrade them. How fast I don't know, but I have had one guy asking me to make more aluminum crankbait molds because his silicone molds don't hold up. I don't know what grade or type of silicone he is using. I would think if they have any expansion pressure they would push silicone molds open. For my own silicone molds I embed an aluminum plate in the back so I can lightly clamp them without distorting them, but I don't think that would stop extrusion at the parting line if there was any pressure at all. I never really had a lot of personal interest in making aluminum crankbait molds before, (I have one stock design) because urethane resin sticks to aluminum. If I made them people would complain about gluing their molds shut when they forgot to use a good mold release. I haven't had time to do more than open the bucket and read the instructions, but this process intrigues me as an alternative. I'll probably make a "no sprue" version of the mini crank and test it along side the regular castable mini crank and some loose beads to see what happens. 1 Quote Link to comment Share on other sites More sharing options...
OIR Posted September 5, 2020 Report Share Posted September 5, 2020 Thermoplastic (polymer) Beads (toystore/ebay/hobby shop) 10-20 sec i microwave in a silicone cup (I do try many things...sometimes it works...sometime it burns) and ..yes it is hot/sticky plastic so be carefull. Quote Link to comment Share on other sites More sharing options...
CNC Molds N Stuff Posted October 6, 2020 Author Report Share Posted October 6, 2020 Alrighty. Finally got around to read the instructions from Hagen's. I also found another source at a similar price. I may buy some from them just to see if their instructions are any different. Quote You may either place mold in oven for 20 minutes at 370 degrees. However, although the material is non-toxic (see MSDS) sent with mold), we strongly recommend boiling your mold with a spare cooking pot. Not only is this the safest way to avoid future food contamination, but the boiling process will provide better heat distribution. The boiling time will vary depending on the type of plug and overall size. A good starting point will be 20 to 30 minutes cooking time. 370F degrees is close to the degradation temperature for most silicone resins. Even cooking silicone should not get above 390F. I know people pour lead in silicone, but even platinum cure burns out. A platinum cure silicone might last a while for boiling though if its well made and reinforced to handle any pellet expansion pressure. It might not. Boiling will "mostly" max out at 212F, but the point that touches the bottom of the pan could still get a little hotter. I think for now I am only going to use aluminum molds for this process, although I do have few silicone molds on the bench I could try with some modifications. I've got a toaster oven on the bait bench for curing powder coat. I'll certainly at least try it to see what happens. In the instructions the specifically talk about a bolt together aluminum mold and no mention is made of silicone mold. I do know one person reported using silicone molds, and that they did not hold up all that long so its possible. Sorry, I have not done more with this. I've been really busy in the shop, and this is only one of many things I am working on and thinking about. I will continue to report back as I learn more. Quote Link to comment Share on other sites More sharing options...
