Paint Problem.

Post your technical queries / problems here!
Post Reply
Message
Author
Penguin45
Posts: 174
Joined: Wed Jan 19, 2011 7:39 pm

Paint Problem.

#1 Post by Penguin45 » Thu May 18, 2017 7:19 pm

I have just painted the wing on my Austin 1800 MkII. It was largely bare metalled and blown over with etch primer. It then had two coats of high build primer which was flatted back with 400 grit w+d, followed by two coats of grey primer, which was flatted back with 600 grit w+d. Top coat is damask cellulose, 50/50 paint + thinners. First coat appeared slightly uneven, so a second coat was applied. This has now had 24 hours to dry, but is showing grey shadows in several areas where it appeared uneven in the first instance.

I'm unsure as to whether this is a coverage issue (It certainly all looked very red whilst wet!) or blooming. If the latter, what should I do about it and hpw can i avoid it recurring?

Thanks,

P45.

User avatar
Grumpy Northener
Posts: 1637
Joined: Sun Apr 03, 2011 8:26 am
Location: Hampshire UK

Re: Paint Problem.

#2 Post by Grumpy Northener » Thu May 18, 2017 8:06 pm

Certainly a coverage problem - I would have put at least 4 - 5 coats of the colour on - reds & maroons are notorious for ghosting effect due to lack of coverage - especially over a primer which is lighter in colour than the topcoat - which is why most professional bodyshops now use coloured primers has it covers with less coats of paint and reduces the costs - Just lightly flat the wing again and reapply a further 4 coats of paint and you will resolve the problem - good luck Chris - any further issues just post them up and I will respond as soon as I can
1937 Jowett 8 - Project - in less pieces than the Jupiter
1943 Jowett Stationary Engine
1952 Jowett Jupiter - In lots of peices http://Jowett.org/
1952 Jowett Javelin - Largely original
1973 Rover P6 V8 - Original / 22,000 miles

rich.
Posts: 6804
Joined: Wed Jan 05, 2011 9:18 pm

Re: Paint Problem.

#3 Post by rich. » Fri May 19, 2017 6:11 am

can you post a pic please?

Penguin45
Posts: 174
Joined: Wed Jan 19, 2011 7:39 pm

Re: Paint Problem.

#4 Post by Penguin45 » Fri May 19, 2017 8:39 am

Thanks for the re-assurance, Chris. I shall do some layering up. Does make you wonder why the instructions are to use a grey primer under a red paint, when there are plenty of red primers available!

Rich, I'll see what I can do.

P45.

Penguin45
Posts: 174
Joined: Wed Jan 19, 2011 7:39 pm

Re: Paint Problem.

#5 Post by Penguin45 » Fri May 19, 2017 6:13 pm

Not sure if these help or not!

Image

Image

Image

Image

Anyway, all now rubbed down prior to another attempt.

P45.

rich.
Posts: 6804
Joined: Wed Jan 05, 2011 9:18 pm

Re: Paint Problem.

#6 Post by rich. » Fri May 19, 2017 7:10 pm

cheers mate :thumbs: i can see what you mean now.. can you post pics of when its done to your high standards..

alabbasi
Posts: 244
Joined: Wed Jan 12, 2011 9:54 pm

Re: Paint Problem.

#7 Post by alabbasi » Sat May 20, 2017 4:20 am

Are you using catalyzed paint? Looks to me that the primer is shrinking under the paint.

Penguin45
Posts: 174
Joined: Wed Jan 19, 2011 7:39 pm

Re: Paint Problem.

#8 Post by Penguin45 » Sat May 20, 2017 11:32 am

"Curiouser and curiouser" said Alice....

Flatted back what had been done so far, and built up a further five coats as per Chris' instructions. Left it overnight. There was still some evidence of the grey streaking, which was disappointing. However, applying a bit of logic reminded me that when I flatted back the first effort, the marking disappeared. Got a nice clean cloth and gently buffed over the affected areas and the paint has come up a treat - no streaking at all. I really don't quite get it!

So, It's got to be left for a while, then I'll see if we can get a proper shone on it.

Al - it's just cellulose and thinners.

Chris.

User avatar
Luxobarge
Posts: 1780
Joined: Wed Jan 05, 2011 3:12 pm
Location: Horne, Surreyshire

Re: Paint Problem.

#9 Post by Luxobarge » Sat May 20, 2017 12:57 pm

I reckon that's blooming - it happens when the atmosphere is a bit humid, as the celly flashes off it goes cold and moisture condenses on it as it's drying. Yes, you can polish it out but you might get problems later down the line in a year or two if it's bad - only time will tell. You really need to spray cellulose in warm dry conditions - as dry as possible.

However, if I were you once you've got a decent depth of top coat on, I'd flat (1200 - 1500 grit used wet) and polish and it'll probably look fine. How it fares in the future will depend somewhat on what conditions it lives in - leave it outside in all weathers and it'll almost certainly bubble and bloom again, but leave it in a warm dry place out of direct sunlight and it'll probably be fine. Mind you, these issues apply to cellulose paint in general, whether or not it has bloomed in spraying, unfortunately especially so on red colours.

Nice one - when you're ready we'd love to see some pics of the whole car!

Cheers bud. :D
Some people are like Slinkies - they serve no useful purpose, but they still bring a smile to your face when you push them downstairs.

Post Reply

Who is online

Users browsing this forum: No registered users and 1 guest