Hi all.

After some attempts I have successfully made a resin infused part and learn t the hard way with the many costly mistakes.

However I am having great difficulty with the clear coat stage.

The clear coat seems to just open many holes and give a nasty irregular (big orange peel like) finishing and has damaged all my attempts.

I had initially suspected it to be release agent in the part expelling the clear coat since the first part came out with a matt finish (due to excessive and unpolished release agent).

During the next attempts I used less release agent and polished the mold thoroughly leaving it with high gloss finish.

The part seemed to come out OK  … but since the part will be exposed to sunlight I opted to get it clear coated.

I also thought it would give the part more depth and a higher quality look and avoid yellowing in future.

We have tried various clear coating methods but it always just opens up many holes again and again…

Has anyone experienced this before ? Help would be greatly appreciated.

• Method : Resin Infusion Process
  
• Resin : Huntsman High Viscosity Epoxy Resin
• Release agent : Huntsman Renlease QZ5111
• Clearcoat : Automive PU Clear / PPG ACS

Doesn't make too much sense though... There's no reason one clear coat would adhere and another one would not. It is certainly possible that one would 'hide' the defects better, ie. a high solids clear would be less susceptible to opening up than a medium or low solids clear. But the issue is still there underneath.

If it's sorted then great! Just be wary that you haven't just found a bandaid solution that will become a bigger problem in a couple of years. 

Sure ... it also didn’t add up.

I changed the clear as a last resort since I had redone all the rest.



Before applying to the carbon we tested on metal and interestingly enough the one that least stuck do the carbon had a better result on metal and vice-Versa.

On pure resin (left over from infusion) both stuck perfectly. So I then blamed the release agent.

To make sure ..... I made a quick sheet and added both wax based and pvc release agent to test.(possible release agent in the fiber opening clear)


The newer clear seemed to perform better again.

My only guess would be possible better chemical compatibility between them ...


Thanks for the reply ... I will keep testing.