Paint respray puzzle

[southerly95]

Resprayed Betty's rear wing last night after sorting a dent. Had prepped the whole wing last weekend with several coats of cellulose primer and finished with wet and dry 1200 and a couple of paint wipes. Sprayed OEW top coat on and looked fine initially but developed what looked like scratches underneath the surface in 3 areas the size of a mug - looked like a lots of Ws, Xs and Ys.

Any ideas what it is and how to sort? It wasn't orange peel - have seen that before. Thanks, John

[bmcecosse]

Just rubbing marks shining through? Flat down - apply more primer - flat again and then try a thin coat of OEW again to see how it looks.

[chickenjohn]

You haven't prepped enough! No need to use 1200 grit on primer, that grade is for dealing with orange peel and runs on the top coat. It is too fine for prime.

What you need to do is sand the top coat off, with something like 180 grit on a DA on the offending areas. Then filler prime again about 4 coats. Then dust over with a light mist very very thin coat of a dark colour- this could be black or dark blue.

Sand this off with 400 grit used dry (blow the dust off the paper with a blow gun- wear a dust mask! or use a vacuum sanding system) then once all the guide coat marks have gone you have a flat panel. Give it a few more coats of filler primer and sand with 600 grit dry.

Finally, panel wipe and tack cloth to de-grease and de dust the panel and apply top coat starting with a thin "gripper" coat.

You should have a lovely paint finish now!

Wet sanding is for top coats, not primer!

[southerly95]

Thanks for replies - I had prepped properly but think I may have put too much primer filler too quickly on OR had a chemical reaction.

I have reprepped with a new tin of primer filler and all ok apart from one bit copied in the pic below so you can see the prob. Magnified but to keep perspective the lines and shadow relate to the wing piping. Ignore the black bit that's a bit of masking tape. Cheer, John.

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