Hi, I received a 5 gallon pack resin from my local supplier a week ago. The pack came with catalyst and one litre of dark purple stuff. I was wonder what it was. Until few days later, I glassed it without adding the dark purple stuff, the resin never cured, so I wonder it could be the problem of catalyst. Then I add 30% of cat into the resin, it needs an hour to kick~~~~~~~~~~~~… I called to the shop, the guy told me have to put 40 parts resin to 1 part of dark purple stuff, following this instruction, the resin kicks in a minute~~~~~~… Then I reduced the ratio 400 part resin to 1 part dark purple stuff, it took 10 minutes to gel. Can anyone tell me what the dark purple stuff is??? And how much I should add to the resin? Thanks in advance. Regards, Crabie
The blue stuff may be colbalt. It is an excellerant. Store it far away from the catalist, as they are very reactive. Colbalt has been used in explosives.
It does sound like a cobalt accelerator. Wear your respirator and work fast!
Sounds like cobalt to me too.You probably have what is called “unsaturated poly resin”,it will not cure without the cobalt.I worked for a boat yard that imported resin from Italy and we added cobalt and other things depending on the job at hand.Keep the cobalt and catylist away from each other as they can eplode if mixed directly together.I could tell you a story about that but I guess the point is made. R. Brucker
Thanks for your reply… Actually how much does it add to the resin? Regards, Crabie
The amount of cobalt that needs to be added is determined by the resin. Most unpromoted resins will have a promotion schedule that comes with it. The promotion schedule will list different amounts of promoters to be added based off the gel time and working temp. Ask your supplier for better specifics. Cobalt and MEKP will explode if mixed directly together!! You are better off buying a prepromoted resin designed for thin laminates. Surfboards are made with very thin laminates compared to standard polyester/fiberglass laminates. Sluggo
Odds are your resin doesn’t have any inhibitor in it if you are promoting it yourself. If you plan on not using all the resin and you promote it all, it will have a much shorter shelf life than you are use to. It will crosslink/gel on its own in a short period of time. Sluggo
I made an error.The resin is unpromoted not “unsaturated” as I wrongly stated.Thanks Sluggo. R.B.