Gel Coat with not enough hardener

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Gel Coat with not enough hardener

Author	Message
Jozi	Jozi posted 12 Years Ago HOT Topic Details
Group: Forum Members Posts: 18, Visits: 60	I had to make a few tiny repairs to my mould and mixed up such a small quantity of gelcoat I couldn't measure it properly. Mixing it 10:1 I had about 7-8gr of gelcoat and I added a bit of hardener that was less than 1gr, but I'm not sure by how much. I just had a look at the gelcoat 18hrs later and part of it is hard but some of it feels a bit greasy and smears a little on to my finger when rubbed. Will it harden out eventually and if so how long could it take?
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H4RTM4N	H4RTM4N posted 12 Years Ago HOT Post Details
Group: Forum Members Posts: 7, Visits: 203	I'm affraid I'll have the same problem. Today I made some repairs on a mould I prepared last week. In addition to the usual gelcoat + MEKP, I added some liquid paraffin (1-2%) to prevent the gelcoat from staying tacky. After 4h, the gelcoat is way less tacky than usual but it's still 'green'. In case it stays this way, is it possible to make it fully cure so it can be sanded and polished? Would I need to put some tape on it? Thanks!
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fgayford	fgayford posted 12 Years Ago HOT Post Details
Group: Forum Members Posts: 433, Visits: 1.2K	Jozi (27/08/2013) I had to make a few tiny repairs to my mould and mixed up such a small quantity of gelcoat I couldn't measure it properly. Mixing it 10:1 I had about 7-8gr of gelcoat and I added a bit of hardener that was less than 1gr, but I'm not sure by how much. I just had a look at the gelcoat 18hrs later and part of it is hard but some of it feels a bit greasy and smears a little on to my finger when rubbed. Will it harden out eventually and if so how long could it take? If this is polyester resin just apply some steady heat to it and it should cure fine. If the gelcoat doesn't have airdry (we call it) it will stay tack on the surface Hope this helps. Fred
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