Problem: Soft and Flexble CF parts ...

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Problem: Soft and Flexble CF parts ...

Author	Message
fibernoob	fibernoob posted 7 Years Ago HOT Topic Details
Group: Forum Members Posts: 34, Visits: 134	Hi All, I have tried to find some info on here but possibly did not use the same search terms so please excuse me if this has been repeated. I have made some CF panels on a glass sheet using 2 x 200gm² sheets pressed together. In one case i have used peel ply on the reverse to clear excess resin. I have noted that these parts and panel came out soft and flexible. It also has a slight wrinkled surface when folded or flexed. The flexibility can be compared to that of a common computer mousepad. Anyone had this happen or have an explanation ? The only reason I can possible think of is ambient temperature, I remember the days where pretty cold and humid during and my workshop is an open space. I have also let the parts rest for a few says hoping that they would cure and harden a little... but no luck. Seems like this panel and other parts I made during those days have all come out the same way... Tags flexible folding soft wrinkled
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Fasta	Fasta posted 7 Years Ago HOT Post Details
Group: Forum Members Posts: 468, Visits: 3.5K	I reckon this must be a resin mixing error or just too cold to cure?? Fastacraft Facebook page
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Dravis	Dravis posted 7 Years Ago HOT Post Details
Group: Forum Members Posts: 592, Visits: 1.9K	A combination of even slightly off mixing ratio and too low temperatures could be the problem. Some resin systems are very critical in relation to mixing ratios -- I did a few tests with EC IN2 -- you need to be within 5-10% of the correct weight. This is almost impossible to do on small batches (Less than 50 grams) IN2 will not harden properly if temperatures are below 16-18 degrees Celcius, even if correctly mixed, they will absorb a lot of moisture in humid conditions, making the resin soft. "Sapere Aude"... Dare to KNOW! The written word is the only truly efficient vehicle for transmitting a complex concept from mind to mind... 103% of all people do not understand statistics... Do not adjust our mind, theres a fault in reality :-)
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Warren (Staff)	Warren (Staff) posted 7 Years Ago HOT Post Details
Group: Administrators Posts: 2.5K, Visits: 7.9K	Definitely a cure issue of some kind. That is almost as flexible as a sheet made with our EF80 flexible resin! Warren Penalver Easy Composites / Carbon Mods - Technical Support Assistant
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Rich (Staff)	Rich (Staff) posted 7 Years Ago HOT Post Details
Group: Administrators Posts: 167, Visits: 4.6K	A couple of questions to help us understand and hopefully advise accordingly: 1)Were these wet laid? 2) What resin did you use?
	Reply Like 4
fibernoob	fibernoob posted 7 Years Ago HOT Post Details
Group: Forum Members Posts: 34, Visits: 134	Hey all.... After reading the replies, remembering what happened and calling the suppliers ... I found out what went wrong I had purchased lower viscosity resin thinking that it would produce less air bubbles during the vacuum process. It occurs that this resin has a slightly different mixing ratio and is more sensitive to temperature. Thanks again for all the helpful input from everyone, nice to see how accurate all the answers are. Tags ambient mixing ratio soft solution temperature
	Reply Like 5