sticky finish

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sticky finish

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FLD	FLD posted 10 Years Ago HOT Post Details
Group: Forum Members Posts: 468, Visits: 2.7K	Thanks Fred
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fgayford	fgayford posted 10 Years Ago HOT Post Details
Group: Forum Members Posts: 433, Visits: 1.2K	FLD (09/12/2015) I make a few parts in cheapo GRP. I have no shame!! I've made some parts recently and I've found the open surface has remained tacky although the laminate has cured. I catalysed at 3% as normal but the resin I use (East coast) used to be blue and is now brown. Could it be the resin blend or have I started doing something wrong? Any ideas on if I can salvage the parts with a solvent wipe or something similar? Hello If it is polyester resin it is supposed to stay tacky so your next layer will bond chemically to it. Polyester comes un-waxed and waxed. Un-waxed will not cure to the surface. Waxed will cure dry to the touch. Its oxygen that that will not let the resin cure to the surface. If waxed (also called air dry) the wax will comes to the surface and provides a barrier to the oxygen in our atmosphere and will allow the resin to cure right to the surface. If your resin is brown it is getting stale but I have found putting more hardener than normal will still get it to kick. Use lots of heat as well. Fred
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FLD	FLD posted 10 Years Ago HOT Post Details
Group: Forum Members Posts: 468, Visits: 2.7K	Nice save! I have a soft mould too. Forgot about that one.
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Hanaldo	Hanaldo posted 10 Years Ago HOT Post Details
Group: Forum Members Posts: 2.5K, Visits: 28K	Yeh sounds like a similar case to mine. Mine did mostly cure, but it had patches that were uncured. Some bits were completely uncured, some were cured but very soft and tacky. It was more of a 'green' cure, like the stage you would want to do a preliminary trim with a razor blade. I managed to save the job I was doing by hot coating it with a batch catalysed at 25% and then under heat lamps for 4 hours. I then put on another layer of fibreglass with a new batch of resin, to save sanding into the tacky stuff still underneath. Luckily mine was just pattern work and I could get away with a disaster like that. Very nearly destroyed a $2000 plug though! Even luckier was that I informed my supplier, with whom I have a very good relationship, and they managed to contact the guy that had bought the other 60kg of the same batch before he got round to building his pool... Edited 10 Years Ago by Hanaldo
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FLD	FLD posted 10 Years Ago HOT Post Details
Group: Forum Members Posts: 468, Visits: 2.7K	Blimey, mine wasn't that bad. It cured but had a sticky surface and a strange rubbery layer that you could just about scrape off with your nail. The main bulk was cured as normal. I used to think resin composition was fairly straight forward!
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Hanaldo	Hanaldo posted 10 Years Ago HOT Post Details
Group: Forum Members Posts: 2.5K, Visits: 28K	Yeh had a similar issue recently, the manufacturer messed up the addition of promoter. I could get it to cure if I catalysed at 25% and got it to 70 degrees for 4 hours...
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FLD	FLD posted 10 Years Ago HOT Post Details
Group: Forum Members Posts: 468, Visits: 2.7K	Answered my own problem, they are bin-bound due to a batch of resin.
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FLD	FLD posted 10 Years Ago HOT Topic Details
Group: Forum Members Posts: 468, Visits: 2.7K	I make a few parts in cheapo GRP. I have no shame!! I've made some parts recently and I've found the open surface has remained tacky although the laminate has cured. I catalysed at 3% as normal but the resin I use (East coast) used to be blue and is now brown. Could it be the resin blend or have I started doing something wrong? Any ideas on if I can salvage the parts with a solvent wipe or something similar?
	Reply Like 3