lurebaz Posted July 27, 2017 Report Share Posted July 27, 2017 Hi, can anyone help me out with this recurring issue i get with bubbles under the surface of resin lures. The explain further this is my method of casting my bodies Check humidity is below 40 before starting the resin is stored correctly mix a and b resin together in exact amounts 9 min pot life resin add micro bubbles upto 10% mix thoroughly vacuum degass the mix for 2 mins pour carefully into the mold (vented) place in pressure pot at 60psi for 2 hours. Once the blanks are set i sand off the sprues and usually notice a few black spots which are bubbles beneath the skin. I can drill them and fill but it takes time. Everything i read indicates that pressure will take care of all the bubbles but yet it doesn't seem to work in my case. Any help would be greatly appeeciated. Thanks Quote Link to comment Share on other sites More sharing options...
Anglinarcher Posted July 31, 2017 Report Share Posted July 31, 2017 The only thing I can think of is that you are taking too much time to get it poured and under pressure. The humidity should not matter at all. Adding MB to the mix can thicken it and speed up the cure a little, but not that much. My suggestion is to get it into the mold quicker and to get it into the pressure pot faster. 1 Quote Link to comment Share on other sites More sharing options...
lurebaz Posted August 10, 2017 Author Report Share Posted August 10, 2017 Hi, thanks for the reply. I am using long pot life urethane, it gets in the pot well before set up starts. Quote Link to comment Share on other sites More sharing options...
Anglinarcher Posted August 10, 2017 Report Share Posted August 10, 2017 Sometimes it is tough to be sure of the problem. I have never had your problem so I don't know if it is a problem with a specific product, a technique, etc. If you can send me a close up picture of the issue I might be able to answer your question. Maybe. Your description of what you are doing seems excellent. I would not even bother to degas first if using pressure casting so you are doing more then I would. Sometimes the devil is in the details so the solution could take some time. Please include a picture of the black spots or PM me and I will help the best I can. 1 Quote Link to comment Share on other sites More sharing options...
armatus Posted September 8, 2017 Report Share Posted September 8, 2017 Hi guys. Im new to this forum. Builder from the netherlands. To reply on the question, my experience with the problem is that when the 2k urethane is old ( more than 2 weeks after opening new bottles) more air is produce when the blank is cured. Thats why I always buy small packages and pour a freshly openened bottle as fast as possible. Hope this will help you solving this problem. Best regards, Armatus Quote Link to comment Share on other sites More sharing options...
Musky Glenn Posted September 8, 2017 Report Share Posted September 8, 2017 I wonder if the bubbles are formed from gas, or are they just air pockets that didn't fill from lack of vibration, for lack of a better term. Good luck. 1 Quote Link to comment Share on other sites More sharing options...
BrianB Posted September 11, 2017 Report Share Posted September 11, 2017 The bubbles under the skin are more an likely from the microballoons.. It can also be from the age of the resin as aramatus explained. If you open up a fresh can and you still get the bubbles under the skin it's the balloons.. Quote Link to comment Share on other sites More sharing options...
