does coupling coat need to set before tooling resin layup?

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does coupling coat need to set before tooling resin layup?

Author	Message
James66	James66 posted 12 Years Ago HOT Topic Details
Group: Forum Members Posts: 10, Visits: 99	Hi making a mould + havnt used uni-mould system before, I know the gel coat has to cure before coupling coat but does the coupling coat need to cure before tooling resin + csm layup? Cheers for the help james
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Shaneer22	Shaneer22 posted 12 Years Ago HOT Post Details
Group: Forum Members Posts: 156, Visits: 14K	After about 2 to 3 hours should be enough time time depending on temperature,the coupling coat does cure a lot faster than toolling coat,which should be left overnight before coupling coat is applied.
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James66	James66 posted 12 Years Ago HOT Post Details
Group: Forum Members Posts: 10, Visits: 99	Ok cheers for that, thank you
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ceebmoj	ceebmoj posted 10 Years Ago HOT Post Details
Group: Forum Members Posts: 5, Visits: 29	Just to check is the coupling coat is taken to tack or fully cured befor the reinforcement is added
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Hanaldo	Hanaldo posted 10 Years Ago HOT Post Details
Group: Forum Members Posts: 2.5K, Visits: 28K	Fully cured mate.
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Matthieu Libeert	Matthieu Libeert posted 10 Years Ago HOT Post Details
Group: Forum Members Posts: 955, Visits: 3.4K	I always make sure its not fully cured lets say (+24h) but laminate on top of it with the tooling resin after a few hours (when its a bit over tacky) to make sure I have a good bond between the coupling coat and tooling coat EC has a written tutorial about it and a video as well on youtube (search for Easy composites bonnet or something like that) to make it easy for you here is their pdf http://easycomposites.co.uk/downloads/TDS/TDS-Uni-Mould-Introduction-and-Application-Guide.pdf Matthieu Libeert Founder MAT2 Composites X Sports website: www.mat2composites.com
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Hanaldo	Hanaldo posted 10 Years Ago HOT Post Details
Group: Forum Members Posts: 2.5K, Visits: 28K	Yeh spot on Matthieu, probably should have been more clear with my response. I meant fully hardened rather than fully cured. As Shaneer said, 2-3 hours at 25 degrees is fine. Give it an extra 2 hours for every 5 degree drop in temperature, assuming you've catalysed accordingly. Be a bit wary of bonding to the skin coat TOO early though, it's better to give it more time to cure than less time. The skin coat is a vinyl ester and the tooling resin is a polyester, and whilst they are both very low shrink they do still shrink and they do shrink at different rates. Bonding to the skin coat prematurely can increase the chances of distorting your mould as your resins shrink. Remember you don't really have a window of time for bonding as you do with the gelcoat, you can leave the skin coat for a year and all it takes is a wipe with acetone and a good scuff up with 60 grit before you can bond to it again.
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