hi all, long time listener, 1st time caller.
I feel the need to make a few comments on various posts I've read in this thread. I've been painting casually and semi-professionally for a few years now - though I consider myself to be an unskilled noob compared to guys that do it for a living, but here goes.
Golden Rule #1
The key to a good paint job? Prep. prep, prep and more prep. Spraying is probably 2% of a good paint job. The more $ and time you invest in materials and care during the prep work, the better your finish will be and the less post-paint buffing etc you will have to do.
as an example, I spent a month working (at nights) on some repairs on a Subbie wagon for a friend and really went the extra mile during prep till I was genuinely happy with the car sitting there with it's primer on. Using 1K Dulon, I just sprayed it on and let it dry - no need to buff, polish, sand, anything - factory finish off the gun. (Not to say this happens every time of course!!)
Equipment:
The more $$ you spend on gear (including safety) the better - it's just that a lot of people can't justify $1000 for a gun for a single paint job - fair enough! I do most of my work with a Welmade gravity gun. They're cheap and a direct rip-off of the DeVilbiss kit (which IMO are the best)
However, I will soon be buying a DVB gun and the quality of my work will reflect that investment (I hope!)
Also, you need a good compressor (12CFM or more), good lines, water traps, clean air filter, good mask (and suit if using 2K), clean workshop, quality body filler(nutech is just re-hydrated donkey shit imo), quality solvents (not supercheap!) quality primer (not resene) and quality paint (not either of those 2) - oh, and don't buy cheap sandpaper either - you end up paying half as much, but using 3 times as much cos it's shit!
But don't take my word for it. if you want a crappy job, go ahead and cut costs!
Comment 1: someone mentioned hosing your garage floor prior to painting to stop dust etc.
Why is there dust in your "paint booth" ????????? Seriously, see the golden rule #1 - cleaning out your shed/garage/booth/kitchen - whereever - is paramount to not having a final coat full of crap!
The main reason tho is the water itself. If your garage floor is covered in moisture, lots of it evaporates into the air, is trapped by the solvents coming out of your high-quality spray gun, and deposited onto your nicely prepped car body - resulting in poor finish - and in the worst case, a cloudy/milky appearance! Oh man, that sucks!
p.s. to remove said milky appearance, empty your paint into a spare clean container, then throw in some two-way thinners and lightly spray it over the affected area - the thinners will soften the paint and help release the moisture. But I'm sure you guys will never need to do that, aye!
Which brings me to....
Golden Rule #2: Cleanliness is far above godliness.
Your work can never be too clean. Prepsol/preparakote/whatever brand/type, once the primer is wet sanded and dried, wipe off the excess with a clean towel and then prepsol that body until the rag comes away clean. While it's drying, you can fire up your compressor, mix up your paint, get your safety gear on and be ready to paint. DO NOT touch the bodywork once it's been cleaned - nothing like oil from your fingers/arm/other bodypart to cause fish-eyes/wrinkles etc.
This same rule also applies to everything - your "booth" - your guns (which you clean before and after every use, of course!!!) air lines, mask filters etc etc etc. I hope you get the picture.
Technique:
This varies between finishes/brands/equipment - you just need to practise and figure out what works best for what you have - I find when mixing color - start with 33% thinners in a small mixing pot and do some test runs and keep thinning/thickening till you work out the required ratio - then you can use a $3 plastic measuring jug from the supermarket to accurately reproduce that ratio everytime you mix a new batch. However, be advised, if the weather/temperature changes, your ratios may need to as well.
Also, 1K clear needs to be thinned approx 50/50 otherwise it comes out like spider webs or goes on too dry. 2K you can just about do what you want, but if you go too thin, you get the dreaded curtains
When spraying,you need to find the right distance from the work to hold your gun - then practice maintaining that distance and a constant speed across the work - also feather the trigger at the beginning and end of each stroke with approx. 50% overlap etc etc - I know, this is real basic stuff but you'd be surprised at how many ppl don't know the basics!
One other trick I learned - once I start painting, the air is always going and then I just need to squeeze the trigger a little bit to get the paint flowing (I'm talking about the fact that the 1st few mm of trigger only flow the air - then it increasingly brings the fluid into the airstream) - this means that you have more accurate control over how much material is being deposited on the work - otherwise sometimes you squeeze the trigger a bit much and *surprise* !! too much=runs. This technique also helps you achieve consistent coats.
While we're on the subject, thin coats > heavy coats. with 1K Dulon, I used to lay down 2 light "dust" coats to get a tacky surface then 2 heavy coats for gloss - but with more modern paints, lighter coats seem better and give a more consistent finish without "shadows" - also, it helps reduce the risk of runs in the finish. This is especially true of metallics, where if you try to paint a few heavy coats, it'll be horrid and all over the place like a mad woman's shit.....
Buffing:
I think this has been covered well here, but I'd just like to enforce the fact that - if you need to buff the finish - start with a 3M medium cut compund on a lambs-wool pad on a rotary buffer - there should be no need for sanding as you followed all the rules and got a beautiful finish off the gun, right??
This will make the paint go dull - don't PANIC! Then move to a fine compund (mothers scratch remover for instance) on an orbital buffer, then a pre-wax cleaner type product by hand, then several coats of pure carnuba wax.
Oh, and don't forget to leave the paint for at LEAST 7-10 days to gas off, otherwise you'll root it! (tho I cut back a 2K finish the other week the day after I painted it - but it wasn't my car, so.....)
Well, I could go on for quite a bit, but I'm sure no one is still reading as they are all asleep at the keyboard by now.
Hope this helps at least someone!
