Carbon sticking to gelcoat

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Carbon sticking to gelcoat

Author	Message
Carbonphoenix	Carbonphoenix posted 4 Years Ago HOT Topic Details
Group: Forum Members Posts: 12, Visits: 134	Hey all, Been having problems, One of my staff has been laying up some new moulds (vinylester tooling), and despite post cure and 10 waxes, the prepreg is sticking badly. So much so, that we have to break the part to save the tooling, to the point of literally ripping it out. What the hell is the issue? over cooked? tooling not post cured enough? Pics attached for reference
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Hanaldo	Hanaldo posted 4 Years Ago HOT Post Details
Group: Forum Members Posts: 2.5K, Visits: 28K	Is it a high temperature wax? And if it is, can it actually handle the temperature you are curing at? Lots of 'high temperature' release waxes are really only designed to handle higher exotherm temperatures, which aren't really that high - often only 80-100° C. I think the highest I have come across is 115°. Edited 4 Years Ago by Hanaldo
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Carbonphoenix	Carbonphoenix posted 4 Years Ago HOT Post Details
Group: Forum Members Posts: 12, Visits: 134	+x Hanaldo - 12/3/2020 2:20:08 AM Is it a high temperature wax? And if it is, can it actually handle the temperature you are curing at? Lots of 'high temperature' release waxes are really only designed to handle higher exotherm temperatures, which aren't really that high - often only 80-100° C. I think the highest I have come across is 115°. It's supposed to be. We have been using it on other mouldings and had been fine 'marbocoat 290'. I haven't checked the data sheet ref temperatures, but will have a gander. Was concerned if my oven is out of calibration and is putting in way too much heat
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Carbonphoenix	Carbonphoenix posted 4 Years Ago HOT Post Details
Group: Forum Members Posts: 12, Visits: 134	+x Carbonphoenix - 12/3/2020 3:18:19 AM +x Hanaldo - 12/3/2020 2:20:08 AM Is it a high temperature wax? And if it is, can it actually handle the temperature you are curing at? Lots of 'high temperature' release waxes are really only designed to handle higher exotherm temperatures, which aren't really that high - often only 80-100° C. I think the highest I have come across is 115°. It's supposed to be. We have been using it on other mouldings and had been fine 'marbocoat 290'. I haven't checked the data sheet ref temperatures, but will have a gander. Was concerned if my oven is out of calibration and is putting in way too much heat
	Reply Like 3
Hanaldo	Hanaldo posted 4 Years Ago HOT Post Details
Group: Forum Members Posts: 2.5K, Visits: 28K	I mean it does also look like the resin hasnt flowed nicely at all, there's lots of dry spots. So over heating could be an issue.
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Chris Rogers	C Chris Rogers posted 4 Years Ago HOT Post Details
C Group: Forum Members Posts: 120, Visits: 933	In general wax and prepreg are not an ideal combo. I have never had good results, even using high temp wax - porosity happens and it is hard to demold clean. A sealer and semi-permanent chemical release would remove the wax variable at least - just be sure to clean the mold really well before switching over. Have you had success with this tooling resin and release wax and prepreg combo in the past? What kind of ramp rate and cook temperature are you using? Type of prepreg? Is the green stuff wax residue or bled-through core-bonding film? Are you debulking the prepreg consistently?
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