Talk Composites - The Forum for Advanced Composites

coating resin degassing - whats going wrong ?

http://www.talkcomposites.com/Topic7881.aspx

By benet - 9/20/2013 6:35:51 PM

Prior to applying a finishing layer of coating resin i thought it would be a good idea to degass it as ive been getting micro bubbles that collect polish.
However for me the degassing process seems to add more bubbles than it get rid of.

Curently Im poring this resin by hand, "tipping out" with a brush and then using a heat gun to pop bubbles. which is OK but id like to degass first.

here are some pics.
Mixed Coating Resin prior to de-gassing
http://www.talkcomposites.com/Uploads/Images/7b252634-0ad5-4da5-b346-5701.jpg


Resin during degassing - i left it like this for 2 or 3 minutes until the bubbles collapsed - then locked off the pump and vented the chamber

http://www.talkcomposites.com/Uploads/Images/9a8334d0-9548-4521-867f-8462.jpg

vacum reading
http://www.talkcomposites.com/Uploads/Images/785240ee-5afa-4098-9df3-3e05.jpg

resin after venting ....
http://www.talkcomposites.com/Uploads/Images/3476e251-3375-4d22-92bc-192c.jpg


after waiting 5 mins to see if the bubbles float out....

http://www.talkcomposites.com/Uploads/Images/c5946ef6-03e0-46ef-aae2-952c.jpg

i tried degassing it again and again but it didnt improve, so after an hour, by which time it had started to warm warm up. i  binned it and used the old method.

What is going wrong ?

Thanks

Ben
By carbonfibreworks - 9/22/2013 4:49:08 PM

The resin in the video looks like it is low viscosity unlike the high viscosity coating resin, try to take your time when you stir the resin as being too quick can introduce air bubbles.
Regards Chris
www.carbonfibreworks.co.uk