Epoxy resin and bad smell

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nils
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Epoxy resin and bad smell

Postby nils » Fri Sep 08, 2017 2:57 pm

Is there any alternative to common epoxy resin? The ones I have used do smell really awful. Even 1 week later my rocket smells quite bad.

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SpaceManMat
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Re: Epoxy resin and bad smell

Postby SpaceManMat » Fri Sep 08, 2017 4:57 pm

What epoxy are you using? If it smells that bad it must be out gassing a lot and that's generally a sign it's not set.
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Digit
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Re: Epoxy resin and bad smell

Postby Digit » Fri Sep 08, 2017 6:03 pm

In my experience the quicker the cure time the worse the smell. The worst I've experienced being 5 minute Araldite. The least odourous being BSI 30 minute. (Trade off is obviously having to hold piece longer)

As SMM mentioned even the worst smelling resin should be totally finished 'doing its thing' after 24-48 hours. Still reacting after a week sounds like something may be wrong.
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Steve Shannon
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Re: Epoxy resin and bad smell

Postby Steve Shannon » Sat Sep 09, 2017 6:56 am

One thing to be aware of is accuracy in measuring the two parts and then mixing thoroughly. If you use an excess of hardener you will end up with uncured hardener. It will never cure, but it will continue to smell.
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nils
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Re: Epoxy resin and bad smell

Postby nils » Thu Sep 14, 2017 4:38 pm

I was wrong. I have polyester resin, not epoxy.
The brand name is MOTIP and it says hardener must be 2,5%. Quite impossible to measure that 2,5% accurately when I do just a small rocket airframe.

Maybe I will experiment with alternatives to resin. There is a 2-component water based floor lacquer. I haven't yet bought it because it is only available in big quantities.

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SpaceManMat
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Re: Epoxy resin and bad smell

Postby SpaceManMat » Thu Sep 14, 2017 7:36 pm

Blake stocks this stuff https://ausrocketry.com.au/accessories- ... grams.html
It's good for Mach 1 and most HPR level 1 and 2 rocket.
You can also get the stuff in different set times.
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OverTheTop
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Re: Epoxy resin and bad smell

Postby OverTheTop » Fri Sep 15, 2017 1:20 pm

Do proportioning by weight (buys a small set of electronic scales).

Measure the hardener first as it is a smaller quantity, then multiply up for the resin mass.
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Re: Epoxy resin and bad smell

Postby nils » Fri Sep 15, 2017 3:04 pm

My previous resin's hardener was a paste in a tube. Now I got new resin that has hardener as a liquid. Much easier to measure.
I used electronic kitchen scale for resin and syringe for hardener. Now I got a nice and not smelling tube.

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OverTheTop
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Re: Epoxy resin and bad smell

Postby OverTheTop » Fri Sep 15, 2017 3:59 pm

Glad to hear you got it sorted nils.

I use a scale similar to this one, purchased on eBay
http://www.ebay.com.au/itm/Silver-Black ... Swjk9ZRSAN
although this one does up to 500g which might be nice :)

Great for weighing ejection charges too.
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