Fisheveryday Posted March 21, 2018 Report Share Posted March 21, 2018 I've been trying (attempting ) to make some fiberglass 2 piece injection molds , I'm able to get the bottom half near perfect but when I pour the top I'm not able to get separated without breaking the top half Ive tried different thickness of resin, waxing with 4 -5 coats of magiurs , painting the bottom half then waxing , cutting the mold in half with a table saw worked best but was a challenge to get a cut perfect with thin portions of the bait like claws. Any suggestions techniques , release agents available would be appreciated . Dale Quote Link to comment Share on other sites More sharing options...
Anglinarcher Posted March 21, 2018 Report Share Posted March 21, 2018 I have not tried making molds from fiberglass, but I have out of difficult materials like Alumilite Vac-Master 50. On my silicones and Vac-Master 50, I find a light coat of Petroleum Jelly works well. Also, most of the problem comes when you try to seperate the molds the first time. I find that is from the top layer seeping around the edges of the bottom half and bonding to it. I remove the bottom half from the mold box and coat the edges of the bottom half with the jelly, then put it back into the mold, then coat the bottom half exposed layer, then proceed as normal. You might try petroleum jelly and see if it works for you. I also get excellent results from Alumilite's UMR but the jelly is available over the counter (Vaseline and the like). Quote Link to comment Share on other sites More sharing options...
SlowFISH Posted March 21, 2018 Report Share Posted March 21, 2018 Anglinarcher is right on with his points.... You can try a PLA release film.... it's basically a water based spray on film that will allow you to separate one part from the other when making fiberglass parts. I used it while making a few motorcycle fenders/molds. You spray it on - let it dry - layup the other part - then after it cures - use water to dissolve the PLA while trying your best to pull the molds apart. Even with the PLA stuff - you gotta work it.... most of this stuff is expected to be used on big highly drafted parts - and even those you gotta bang around a bit.... on small things like we use - its tough. Look up the PLA release film online.... it's not expensive from what I recall... J. 1 Quote Link to comment Share on other sites More sharing options...
Anglinarcher Posted March 21, 2018 Report Share Posted March 21, 2018 32 minutes ago, SlowFISH said: Even with the PLA stuff - you gotta work it Oh yes, and the jelly to. I normally take a cold chisel to the seam line on the Vac-Master to open it the first time. But, sweet after that. Quote Link to comment Share on other sites More sharing options...
Uncle Arnies Tackle Posted March 22, 2018 Report Share Posted March 22, 2018 9 hours ago, Anglinarcher said: I have not tried making molds from fiberglass, but I have out of difficult materials like Alumilite Vac-Master 50. On my silicones and Vac-Master 50, I find a light coat of Petroleum Jelly works well. Also, most of the problem comes when you try to seperate the molds the first time. I find that is from the top layer seeping around the edges of the bottom half and bonding to it. I remove the bottom half from the mold box and coat the edges of the bottom half with the jelly, then put it back into the mold, then coat the bottom half exposed layer, then proceed as normal. You might try petroleum jelly and see if it works for you. I also get excellent results from Alumilite's UMR but the jelly is available over the counter (Vaseline and the like). I also get excellent results from Alumilites UMR. 9 hours ago, Anglinarcher said: Quote Link to comment Share on other sites More sharing options...
Fisheveryday Posted March 22, 2018 Author Report Share Posted March 22, 2018 Thanks for the advice will pick up a can of the umr , appreciate the help have gone through allot of resin and allot of waste, I've got allot of ideas for what I want In a lure but so fare allot of work and no baits lol I didn't want just start buying things Thanks again Dale Quote Link to comment Share on other sites More sharing options...
SlowFISH Posted March 23, 2018 Report Share Posted March 23, 2018 21 hours ago, Fisheveryday said: Thanks for the advice will pick up a can of the umr , appreciate the help have gone through allot of resin and allot of waste, I've got allot of ideas for what I want In a lure but so fare allot of work and no baits lol I didn't want just start buying things Thanks again Dale If you don't wanna waste money/time/etc... get a different hobby!!! LOL!!! Innovation cost money.... no matter if your the most frugal of people - just be prepared to have things go wrong and always buy a little more material/supplies than you THINK you'll need.... you'll need it!! LOL!! Good luck! J. Quote Link to comment Share on other sites More sharing options...
Fisheveryday Posted March 23, 2018 Author Report Share Posted March 23, 2018 J, I did that with the first gal of resin lol Each one is coming out better and better but sure did stink breaking the top half each time i went seperate the halfs UMR should be here in a couple days Thanks Quote Link to comment Share on other sites More sharing options...
Anglinarcher Posted March 23, 2018 Report Share Posted March 23, 2018 On 3/21/2018 at 10:27 AM, Anglinarcher said: I remove the bottom half from the mold box and coat the edges of the bottom half Just remember to do this, it makes a huge difference and is the one thing I don't see done in most videos. Quote Link to comment Share on other sites More sharing options...
Vodkaman Posted March 23, 2018 Report Share Posted March 23, 2018 (edited) I have made resin molds, and find floor wax very effective as a release agent. Be generous with the wax, as the heat generated in the curing process will melt the wax and give you a good contact between the two halves. I apply a little heat from a gas blow torch to melt the wax, then brush it on with a half inch cheap brush. Try not to burn the house down Dave Edited March 23, 2018 by Vodkaman 1 Quote Link to comment Share on other sites More sharing options...
