Curing Epoxy

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Curing Epoxy

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Alexandre	A Alexandre posted 8 Years Ago HOT Topic Details
A Group: Forum Members Posts: 4, Visits: 11	Hi, I have a question regarding curing epoxy to get the best results. The project is a hand layup of fiberglass 3 oz and I'm working with a room temperature curing epoxy with the following properties: - Gel Time (@ 21C) 38 min - Demold Time 24hr - Deflection temp 53 C - full cure at room temperature 7 days I'm a lite confused about what is considered the " curing'' and "post-cure" period, when and how much heat to apply (and for how long). Thanks Alexandre
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Alexandre	A Alexandre posted 8 Years Ago HOT Post Details
A Group: Forum Members Posts: 4, Visits: 11	+x Alexandre - 11/2/2017 1:21:33 PM Hi, I have a question regarding curing epoxy to get the best results. The project is a hand layup of fiberglass 3 oz and I'm working with a room temperature curing epoxy with the following properties: - Gel Time (@ 21C) 38 min - Demold Time 24hr - Deflection temp 53 C - full cure at room temperature 7 days I'm a lite confused about what is considered the " curing'' and "post-cure" period, when and how much heat to apply (and for how long). Thanks Alexandre Oh and how the heating affect the full cure time?
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Warren (Staff)	Warren (Staff) posted 8 Years Ago HOT Post Details
Group: Administrators Posts: 2.5K, Visits: 8.5K	The demould time is when you can remove it from the mould. The epoxy will only be partially cured at demould and depending on temperature, can take a few weeks to a month or two to fully cure internally. A post cure is used to either accelerate the cure process and/or to maximise the HDT of the resin by doing an additional higher temperature cure after the main cure at room temperature.. The manufacturers data should list the recommend post cure cycles and if you can cure the resin at elevated temperature from the outset. Warren Penalver Easy Composites / Carbon Mods - Technical Support Assistant
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Alexandre	A Alexandre posted 8 Years Ago HOT Post Details
A Group: Forum Members Posts: 4, Visits: 11	Thanks for the quick answer! So main cure and post-cure should be specified by the manufacturer? In my case there doesn't seem to have this information, can anything be done in this case? Alexandre
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Warren (Staff)	Warren (Staff) posted 8 Years Ago HOT Post Details
Group: Administrators Posts: 2.5K, Visits: 8.5K	+x Alexandre - 11/2/2017 1:44:26 PM Thanks for the quick answer! So main cure and post-cure should be specified by the manufacturer? In my case there doesn't seem to have this information, can anything be done in this case? Alexandre I would definitely email the manufacturer. If they have no data on even the simplest room temperature cure times then I would probably consider then fairly incompetent! Warren Penalver Easy Composites / Carbon Mods - Technical Support Assistant
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Hanaldo	Hanaldo posted 8 Years Ago HOT Post Details
Group: Forum Members Posts: 2.5K, Visits: 28K	Not uncommon to find no post-cure data, but generally you should always be able to find a 'Tg' or 'HDT' value, which is the upper temperature limits of the resin. For most entry level epoxies this is around 60 degrees. If you can't find any data at all, I would hazard a guess at it being around a 60 degree Tg, so you could do a post-cure of 60 degrees for 16 hours. Ideally you would ramp up to this temperature slowly, 0.5-1 degree per minute.
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Alexandre	A Alexandre posted 8 Years Ago HOT Post Details
A Group: Forum Members Posts: 4, Visits: 11	I've gotten word from the manufacturer and indeed the epoxy is not designed for high temperature applications. Hence, they don't suggest any curing schedule.
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