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[Kieran]

Hello everyone
Bought a compressor with a spray gun the other week. My front bumper was slightly damaged whilst in Italy and instead of giving it to a body shop to repair I decided to do it myself. Removed the bumper and all fixings lightly sanded the surface and purchased some paint, thinner and lacquer from a local paint supplier. All is going well and the bumper has come out a treat. My question is how do you get a smooth surface once lacquer has been applied. New to this spraying lark but really enjoying the great finish. Would just like some helpful tips.
Cheers

[Terbs]

Do you mean after you have applied Lacquer ??

If so....use a very fine wet or dry, and gently flat it back, 2500 minimum or 3000. Once it is nice and flat, you then use a very fine compound to polish it out, then apply a really good polish and buff up. Make sure the lacquer has had a few days to really harden, otherwise you won't get a good shine, and you could cut through the lacquer

Sorry, just noticed you amended 'lawyer'

[Kieran]

Thanks for that. Yes after lawyer I mean lacquer has been applied. Didn't realise it takes so long to harden. Feels dry already.

[Terbs]

If you read a few of the tech details, some say don't polish for 14 days !!!! I don't leave them that long, but although it feels dry, it can be soft underneath. Be patient. Its not worth mucking it up. Also remember in bodyshops, most paint is stoved on, therefore hard quicker.

Out of interest, what paint did you use....obviously base coat and laquer, but what type, ie: acrylic, etc.

[Kieran]

Ummm not sure. As said new to this but went with the suppliers recommendations. Base coat mixed with base coat thinner 2 to 1. Lacquer is RFU clear.

[chrisgixer]

is it necessary to flat the paint between coats? Or even flat and polish the paint prior to lacquer?

[Kieran]

Or is it possible to just flat it at the end once lacquered.

[pauls]

If its a good quality paint in a good can or spray gun no need to flatten before lacquer. As said laquar it let it dry for a couple of days then wet and dry sand with lots of water until feels smooth. I normally dry it with a hair dryer then use t cut until it looks smooth with no orange peel. Then a good wax snd polish.

[Terbs]

Its not necessary to flatten between coats ie: base then lacquer....unless you get a foreign body pays you a visit. It happens occasionally. Let dry thoroughly and flatten then apply coats again. There are some who flatten between, personally in all the years I was spraying, it did not occur, unless a foreign body or a 'slide' by too much paint.
One major mistake is to try to put too much paint on in one go.....do not be tempted. Build up slowly, a few coats with a few minutes between. The coats will go off quicker, and be more even. The same applies to lacquer.
The problem is people see me and others who have had years of experience seemingly wacking the paint on with contempt, and basically making it look easy. It is reasonably easy if you take your time. I take the same attitude towards welding...I can't weld to save my life, but you watch an experienced welder and it looks so easy. To me it ain't

[Nick W]

Nobody has mentioned the gun you're using yet.
I struggled with crap finishes until I swapped to 2pack paint, and put a smaller needle in the gun. Many of the cheaper guns are sold with far too large a needle that would be excessive for filler primer. I recently tried a LVLP gun, and even my poor technique gave A glass smooth finish, which is pretty impressive for a £25 tool!
A small gun will want a needle in the 1mm range.

[Terbs]

A lot of the guns are sold with a 1.5 nozzle...but you need, as Nick says, a 1.0 to 1.2. I find 1.2 suits me a treat, but as I said earlier, I have 20 years experience at this game. But even a 1.5 can turn out the goods if used properly.

[chrisgixer]

Personally always struggled with how much paint to apply as you say. I found a lot of thin coats never really added up to smooth shiny finish. It just looks like a load of coloured dust on the part.

However if I go a bit further, and apply enough so the dust joins up as a fluid layer after I've stopped painting, it kinda works. I often wondered if I had the ratio of paint v thinners correct though, but never got round to experimenting further.

The gun was a cheap item probably with the wrong nozzle and I had trouble getting the regulator set correctly as well. ...sort of got there in the end though, just, ish

[Terbs]

If you did not get runs, you are half way there Chris

Thinning too much will give you a 'clear dust' effect. Practising, even on a sheet of hardboard will allow you to check thicknesses. Too thick and orange peel....not necessarily runs, depends how thick you apply the coats. Too thin and you will be, in effect, trying to cover with coloured thinners. Providing you get a nice even base coat, the lacquering coats can be 'played with', providing there are enough coats on to avoid cutting through. In an ideal world, the final coatings of lacquer would require the minimum of doctoring.....but we are talking home respraying here, in enviroments that consist of draughts, creatures, dust, etc.
However, even using spray cans can give a quality finish if the preparation is right, use plenty of water for flatting, and blending the lacquer. Not using the correct grading of wet or dry will leave minute scratches, and which, unless you use plenty of Primer filler, and plenty of water, (it does not matter how many coats you put on, with the modern base coats and lacquers,) you will still see these tiny scratches at the finish.
Sorry to be long winded, but this is something else where people shortcut.
There is an art to masking up, do not shortcut it. It is laborious, after all that prep, and you want to get to spraying bit. Once you have primed...do not be temped to flatten the primer and keep the masking tape on for the final coats. You will regret it. Take the masking tape off, completely dry and blow out any dust or particles of sanded paint. Then mask up again. If you don't do this, laborious as it is, once air is sprayed to the surfaces around the tape, you can bet your bottom dollar that there will be water or some foreign object will blow out onto your work. Its down to patience......and you will be rewarded with a finish to be proud of.

[minifreek]

I always leave a painted panel at least 2 weeks before colour sanding and polishing...

I always use U-Pol paints, especially the proffesional lacquer. I can't remember the U-Pol number...

I get good results from aerosols, I have a spray gun with various nozzles, ut find it easier with aerosols. Probably me being lazy and CBA setting up the compressor and spray gun...

[Terbs]

minifreek....you are the type of person with the 'cba' attitude that is totally alien to the world of paint spraying.
But the sh1t part is, your finishes usually come out bodyshop perfect