Is it worthwhile degassing my coating resin in my vacuum chamber?

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Is it worthwhile degassing my coating resin in my vacuum chamber?

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FiftyPence	FiftyPence posted 12 Years Ago HOT Topic Details
Group: Forum Members Posts: 26, Visits: 264	Is it worthwhile degassing my coating resin in my easycomposites vacuum chamber before brushing it onto my part? Thanks in advance for your advice.
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benet	benet posted 12 Years Ago HOT Post Details
Group: Forum Members Posts: 59, Visits: 373	carboncactus (21/06/2013) benet (21/06/2013) I would like to know however as i'm new to degassing is it normal for the resin to get worse before it gets better in the degassing process. I find that when i add heavily stirred ( big bubbles) resin to my chamber the big bubbles quickly go but are replaced by tiny ones that take a a further 10 minutes or so to finally rise and pop in my chamber. is this normal or do i have a leak or something causing a problem ? How big is your vac chamber? I made a large one (about 10L) and it took way to long to evacuate. Eventually I made one just large enough for a cup of resin: It evacuates in less than 30 seconds (tested with gauge) If you get any bubbles after evacuating, what you're seeing is the solvent evaporating. my chamber is pretty small, i use an asparagus steamer, it just holds a pint size plastic cup. "Solvent evaporating" is that a problem ? When i degass, quite quickly the resin appears to "boil" a bit as the bubbles expand rise and pop but if i take the resin out of the chamber at that point its full with tiny bubbles that where not there when i started.. If this is solvent evaporating what should i do ?
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carboncactus	carboncactus posted 12 Years Ago HOT Post Details
Group: Forum Members Posts: 243, Visits: 1K	I guess it is technically "boiling", as youre lowering the air pressure, therefore lowering the boiling point. This happens somoetimes when you infuse with polyester. When you degass, air will be evacuated fairly quickly. It's a 2 minute job, once you see the resin start to foam up and rise, stop. Let it settle, then evacuate a bit more. If it doesnt settle, air the chamber and youll see the resin flatten almost instantly. Pull some vacuum again, it should rise, but not so much. This is enough, if you start evacuating the styrene youll end up with a thicker resin, making the job harder for yourself.
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benet	benet posted 12 Years Ago HOT Post Details
Group: Forum Members Posts: 59, Visits: 373	thanks carboncactus thats very useful, maybe the process is quicker than i thought. Im going to have to experiment some more.
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