An important resource for a DiYer about epoxy bonding :
Some other tips that may help someone. https://www.youtube.com/watch?v=3Pc-Sd_J26E
(Yes I am having a few issues with epoxy & getting a good finish)
Anyone used Agent-F ? is it Xylene & Paraffin wax?
For information to help others. Today I did a hot coat of epoxy, it has turned out 100+% better than the last coat that I spent hours sanding back.
The difference was:
- Sanded down the surface to give a surface to bond onto.
- Wiped down with Denatured alcohol (AKA Methylated spirits , Metho) waited till 100% dry
- Added a mixture of of ~8%paraffin wax & xylene ~5ml per 100ml of epoxy.
After applying the epoxy evenly I walked away, 3 hours later when i went back I was very happy with the surface finish.
Not sure if it was the surface preparation or the Paraffin/Xylene mix but it has made a huge difference. No fish eyes very clear, glass like finish even before sanding & polishing. may not even sand & polish this coat.
For a good surface finish:
apply a spray/cloud of acetone with a plant water sprayer to watch the air bubbles escaping from the epoxy surface (cheap method in a well ventilated room)
Degasing the finish epoxy coat before application with a vacuum pump has a nice effect too.
I do not disagree however, some water sprayers are not accepting of acetone or are just low quality & fail after a few pumps. I will try this method again, as I worry the xylene &wax will reduce the strength by not bonding to the prior layer. Your thoughts ?
I boiled the epoxy when I tried the degassing method. Since then I have started to build a vacuum chamber with a clear lid so I may have better luck next time. Thanks for the advice!
So true. Acetone moltens/dissolves some plastics. Trial and error method here.
Never tested. I wouls ask on a shape forum.
As you may know, it is not a real “boiling” as water boils at 100 degC.This is not a state change so the temperature should not rise (if you don’t do it in the sun). It’s just the air that is removed. So the resin must keep its properties.