What's making the paint go like orange peel?

[Luxobarge]

2 pack tends give an apperance that the car has been dipped in a vat of plastic.

Exactly! Put so much better than I did....

[Morrisand944S2man]

Longer drying times for the cellulose but it is far safer to use if you do not have access to a proper vented spraybooth area, and is very forgiving when you make mistakes - 2 pack is very good if you have the right workshop facilities such has a proffesional spraybooth, airfed masks etc - if you do not have these - please do not take the risks - I worked within this industry when 2 pack paint came upon the scene and a lot of guys took a lot of risks - those guys that I knew are now paying deeply for the risks taken - today with poor health / breathing problems. Play safe and stick to the cellulose products - granted it is harder work but the results are worth it.

NO! Cellulose dries in minutes as it dries by solvent evaporation. I have used 2K as well and it dries by chemical reaction with the hardener and remains softer and prone to finger marks and picking up dirt when handling the fresh panels for longer.

I found this out when spraying items in the booth at college, the Celly Minor panels were dry enough to handle gently after an hour at 25C in the booth, but the 2K on the panels of my 944 were still soft even after over an hour and a few 65C bake cycles. The 2K 944 panels picked up some fluff and grit from the boot carpet of my car on the way home, this was less of a problem with cellulose.

2K out of the gun has a "plasticky" over shiny un natural look to it , whereas Cellulose has a more natural shine that you would expect to see on a classic car. the difference is less if you wet sand and machine polish both though. Although I have found cellulose top coat easier to wet sand and machine polish than 2K. Cellulose is only really more work because it takes more layers to get the film build because it dries by evaporation.

[Grumpy Northener]

NO! Cellulose dries in minutes as it dries by solvent evaporation. I have used 2K as well and it dries by chemical reaction with the hardener and remains softer and prone to finger marks and picking up dirt when handling the fresh panels for longer.

You are quite wrong - cellulose can take several weeks to dry - I was apprenticed into classic car restoration and taught by guys of the old school - once all panels / shell structure was complete in preperation - etching primer was applied prior to several coats of hi build primer - everything then stood untouched for two weeks - a guide coat was applied - flatted back and minor imperfections cought at this point - the panels were then subject to further primer coats and again stood for two weeks to harden off - guide coat / flatting back process reperated before several cellulose colour coats were applied and then stood two weeks - flatted back again and final top coats applied - the panels / car now stood for a further three weeks proir to flatting by hand and hand polishing which took over a week - paint was never machine polished - the restoration bills were huge and that was 30 years ago !

[Morrisand944S2man]

No I'm not wrong! I'm quite right! If you read my post I did not say "cellulose fully hardens in 1 hour" I said cellulose dries faster than 2K so that it can be handled and moved within 1 hour, whereas 2k cannot- such as from a spray booth back to your own garage.

I agree, I would wait a week before wet sanding and machine polishing.

Please read what I actually wrote and not tell me I'm wrong on something I did not say!!!!!

I've also been taught by guys with 30/40 years experience in restoration and bodywork.

[Rhythm Thief]

I suppose my experience of painting cars with rattle cans and leftover Dulux Weathershield is out of place here?

[pryantcc]

This is all most interesting stuff guys, thank you for the benefit of your experience!

The whole cellulose versus 2 pack debate prompts another question:

If I were to change tactic & go for cellulose top coat, would it stick to the panels which I have already primed with 2 pack?

I lied a little bit at the start when I said I had no experience, I repainted the back end of my Merc 190 in cellulose a couple of years ago. It's a little bit matt, I've never polished it, but the rest of the paint is matt too from weather, so it doesn't look too bad. Not washing it helps too!

[Grumpy Northener]

Rhythm Thief - We all have a place be it rattlecan, leftover dulux or proffesional painter

Now is just me that has concluded that 'Morrisman' would argue over fresh air if it was rationed

[m.thaddeus]

Hello Again

This has all been very interesting. Cellulose will be 'touch dry' very quickly, but not fully hardened for some days, this is all down to the thinners evaporating and is governed by temperature and to a lessor extent humidity..

2k is designed to chemically harden in a few hours - dependant on the speed of the activator and the ambient temperature,-but as anyone who has sheeted up a newly sprayed car will tell you; - it still looses solvent for weeks if not months. The initial 'flashing off' is down to the solvents evaporating.

Celly spayed over 2k primer is a good way to go as a compromise between stability and a classic look. It is also good from a practical point of view.
Whatever you do with the top coat the primer is not going to move as the thinners is not going to soften it up.

I recently painted about half a Stag using custom 2k rattle cans, while working at the owners home. The finish is as good as anything from a pro shop. Never underestimate the Aerosol.
And that book... it aint too bad. Thank you.

[JPB]

custom 2k rattle cans

Interesting!

A recommendation for such a product would be great - coming from you - since you clearly know far more about paint and its use than most of us.
Are you able to advise us of the brand and availability of the cans that you used, please?

I did once paint a small car (an April Yellow Reliant kitten saloon) from aerosols and the only thing I did to ease the process was to stand each can in a pan of warm water before using it. The finish on that car was actually pretty good, but my preparation was the weak link so, although the shine was deep and the finish smooth, it soon parted company from the gelcoat, which I evidently hadn't prepared correctly.
However, I'm sure that many forum members would love to read a "how to" from you on this subject.

Apologies to pryantcc for asking this in your thread, hope you don't mind too much, it seemed the ideal opportunity since the paint specialist had already posted here.

[pryantcc]

custom 2k rattle cans

Interesting!

A recommendation for such a product would be great - coming from you - since you clearly know far more about paint and its use than most of us.
Are you able to advise us of the brand and availability of the cans that you used, please?
I'm sure that many forum members would love to read a "how to" from you on this subject.

Apologies to pryantcc for asking this in your thread, hope you don't mind too much, it seemed the ideal opportunity since the paint specialist had already posted here.

No need to apologise JPB, it's everyone's thread!

I'm off out to sand some more primer.............