I agree about the curing. Learned it from Del Brengman.
Never had problems. He showed me his Epoxy Curing oven,
and I made one. Curing between 100-110 deg seems to
work great. Pretty simple:
Make a box out of insulation board (foiled on the inside),
sized to accomodate the wings you're bagging.
Couple of 100 wat lightbulbs, computer fans to circulate air,
Floor - heater thermostat, (110VAC) and a $10.00 Digital LCD
thermometer w/probe from Radio Schack.
This works great, and you can see the temperature on the
thermometer, and it is uniform. ... HOWEVER, and electic
blanket sounds easier, and if it produces consistently
good results, then, it sure would save space and be more
convenient for small areas.
-Paul
Electric blanket... Hmmmm... Sounz cool, if you can really
regulate the temperature relatively uniformly.
"Kappus, John" wrote:
>
> Brian,
>
> I have bagged blue, pink, and beaded white foam with West 60 minute resin.
> I have found that it is very important to thoroughly cure the resin. In my
> experience, a 12-18 hr cure at 70 degrees F is not enough. The cure rate
> approximately doubles for every increase of 10 degrees C. I always put an
> old electric blanket on HIGH over my lay-ups and raise the temp to around 95
> degrees F. I leave the vacuum on for a minimum of 24 hours. This is
> equivalent to over 50 hours at 70 degrees I noticed that the paint releases
> easier on FULLY cured parts. Epoxy also cures harder at elevated temps.
> Others have written about an insulated heat box to raise temps further, but
> bubbling of the resin can result at too high a temp.
>
> From: Brian <[EMAIL PROTECTED]>
>
> Hi,
> My problem:
> I've attempted my first bagging attempts and have produced 3 small slope
> wings. 1 to 5 days after laying up wings using West Systems for one and
> Araldite LC 3600 and LC 249 Hardener for the last two and Dow Roofmate
> Blue foam, I get bubbles forming in places on the wing.
>
> Used 15/18 inches for vacuum.
> Beds were outside the bags, except one where the bottom bed was inside.
> Under vacuum for 12/18 hrs.
> Mylars removed 24/36 hrs after lay-up. One painted, two not all removed
> ok.
> Average temp during lay-up 20degc/70degF
> Ample paper towels inside bag to bleed air and ski rope around perimeter
>
> All excess resin scrapped off glass lay-up before bagging.
> Wings looked fine when removed but bubbles formed next day or in the
> case of the latest one "5" days later!
> Bubbles were generally random and not very large but were predominately
> in areas away from the L.E., T.E. and wing chord centre.
>
> Sleepless in Stafford
> Brisbane
> Australia
>
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