Ive given some resin infused parts to a paintshop for clearcoating

Overall the surface is pretty good, some areas of porosity,pinholes but its minor.

 

My guy prepped with 1500 grit, scotchbrite and degreased.

He put on several coats and had issues with pitting, unevenfinish.

 

Wondered if anyone had any input or ideas on process andpreparation.

Whenever i have done any small parts myself i went for600/800 grit prep, couple coats of lacquer, then 1000/1200 grit and finallacquer coats.

Im wondering whether the 1500 is not enough grit, and the lacquer is seperating/repelling

 

Please see pics attached 

I've had this.  I have two strategies for getting round it:

1) I find that sealing the part prior to spraying helps.  I do this with very dilute 2k lacquer which I brush on.  Use the brush to work it well into the surface.  Let that dry then denib and apply another coat or 2.  Then spray.

2) Dust coat the part several times (letting it dry after each one) until you have a full film of dust coats then spray.  I find this works but I dont feel comfortable with it for some reason so prefer option 1.

Hope that helps.

I've been struggeling a lot with 2K spraypaint as well...

FLD's methods are fine for pinhole filling.  Brush or wiping it on by hand tends to be the most reliable.  You can then flat back and spray and the dimpling should be gone as the pinholes should be filled.

Warren Penalver
Easy Composites / Carbon Mods - Technical Support Assistant

Thanks. What is dust coating? Is this a dry application asopposed to a wet type coat?

Do you find with you brush seal approach you have to flat itback smooth before the proper final spray coats go down?

Thanks Warren, just seen this after i posted my reply.

I will look at trying this next time.

I dilute 2k lacquer with standard thinners (or gunwash if I'm feeling particularly tight). For a sealing coat I dilute it down A LOT. 1 part lacquer, 1 part activator and 4 parts thinner. This means you get a thin coat that has very few brush marks. Once dried give it a light flat back with 380 and recoat. Repeat until pin holes are gone and then spray. For spraying I halve the amount of thinner.

A dust coat is a spray application where you leave it with a dusty finish ie not a fully wetted out film. Its often used when laquering colours to 'hang' a fully wet film on without getting sagging or runs.

Great reply FLD. I thought as much. When i used to sprayplastic without primer id go for thin dusting to act as a primer.

 

Thanks for all the help guys

 

This is hopefully a short term fix until can get the uvstable EC gelcoat spray painted in moulds, this looks much more efficient.

Just need to get a booth set up!