GREAT WRITEUP ON PAINTING

[URL]http://www.endlessmotorsports.net/FORUM/index.php?topic=20.0[/URL]
 
At school, (WyoTech) we finished body work with 220 grit. Then you put 3 to 4 layers of a high build primer on. Wait till cured per instructions. Then wet-sand with 400 until you get the major highs down, then go to 500 till you get the shiny dots gone, and then go over it easy with 600 just to get it that much more smooth.

When it comes time for paint, take your time. You need to have proper distance, fan pattern, and speed. If you go to fast, the same with to far away, you can create a dry spray which will result in coarse paint. If you go to slow, or are to close, you could create runs/sags and also if it is a metallic, completely change the color because the flakes will tumble as they sag and not lay flat like they should. Proper distance AND spray pattern is 6" to 8".

On the guns at school, Devilbiss and Sata, a wall pressure of 48 lbs was adequate for compensating the pressure drop in the 25' hoses and in the gun to get approximately the correct spray cap pressure. You should have the fluid (paint) needle backed off. To adjust it, pull the trigger back and screw it in until you can feel the trigger getting pushed back forward, then back off it slightly and then use the thumb nut and snug it up so it doesn't move.

TAKE YOUR TIME - Have at least a charcoal respirator on for the painting stage, preferably a fresh air mask (expensive for those that are only going to do this once).

Start on one side over the vehicle. At school, we started on the drivers pillars and worked up them to the rain guards/rails and then across the roof almost as far as we could reach. Then you walk around to the other side and catch that wet edge and keep spraying front to back across the roof to that rain guard and down the pillars. Then you can choose how to do the sides/front/rear. Usually we did the passenger side in long sweeps instead of panel by panel. Then you work across the hood, again like the roof, from the passenger side to the driver side, sweeping up and down it from the bumper to windshield. Then do the bumper. Then you do the driver side and back up over the trunk as you choose. By this time, you should be about 12-17 minutes into the paint-job which is time for another coat because it already flashed (usual is 15 minutes). Have somebody assisting you pre mixing the paint and getting ready to pour it into your cup on the gun.

Keep that process going until you have 3+ coats of paint on BEING CAREFUL that you do not bump the paint with anything. WATCH THE AIR HOSE and make sure it is clean prior to painting. Let it flash for an additional 5-10 minutes after you finish the last coat, DO NOT spray the "extra" paint on. If you don't get the same amount of coats / coverage on the entire car, it will most likely be noticeable, especially depending on your primer and paint colors.

We NEVER wet-sanded the paint. I don't remember learning about it. The only reason you MIGHT need to wet-sand the paint is if you get a run / sag. Then you have to let it sit for an hour or so so it cures and then you can wet-sand it without tearing the paint off b/c of it being so soft. YOU NEVER WETSAND THE FINAL COAT OF PAINT. You should have, at minimum, 1 coat of paint over the wet-sanded area. DO NOT OVER SAND, the worst thing you could do is sand to far and go down to the primer.


Then comes time for spraying the clearcoat.

COVER YOU SKIN, NECK, HAIR. Clearcoat is sticky and irritates the hell out of you when it lays on your hair. It is recommended to have a Fresh Air Respirator for this. Charcoal masks do not protect enough but is "fine" if you are only going to do it once.

AGAIN, take your time. Do the same process as above for the first 2-3 coats (depending on how much you got). Then for the final coat, add A LITTLE more reducer than the mixing ratio calls for, this will allow it to flow a little better and fill in some of the orange peel you may have created from improper spraying techniques which in turn, creates less sanding in the end. Once the final coat is on, let the car sit. If you have access to baking it, do so. Then let the car cool and sit at least 12 hours so the clear isn't soft before you wetsand the clear and then compound/glaze it. If you do not have access to baking it, let the car sit for 3 days till it is cured. Make sure it is in a dust / dirt free area with limited to no traffic and no wind or bugs.


Once cured, you wetsand/compound/glaze the clear if you want show quality finish.

You should start with no lower than 1,500 grit. DO NOT USE 1,000 grit unless it is on the immediate area of a run or sag. NEVER GO LOWER THAN 1000 GRIT. Put a Tbsp of Dawn dish liquid soap into a bucket and fill it with at least a gallon of water. You want to sand in 1 direction, then switch 30* to the other direction. Once everything is sanded with the 1,500 grit, allow the car to air dry and check over the work for any shiny spots. The entire car should have a dull appearance, almost a white to it. If you have shiny spots, you didn't sand enough in that area. DO NOT WORK ONLY THAT AREA FOR SANDING THE CLEAR. You don't want to oversand the area and create a semi-flat area and change the reflection in the clear when all is said and done.

Once finished with 1,500 grit, go to 2,000 grit. You should final sand the 2,000 grit in the opposite direction you final sanded the 1,500 grit. Allow the car to dry and look for any sanding marks going the direction the 1,500 grit was going. If you see them, keep sanding with the 2,000 grit.

Once the sanding marks are gone, you can choose to either start compounding the car now, or go to 3,000 grit. If you choose 3,000 grit, do the angle you did for the 1,500 grit until all the 2,000 grit scratches are gone.

COMPOUNDING

Use an orbital buffer if you haven't used a rotary buffer before. If you do use a rotary buffer, stay off of edges and don't stay in one spot to long. If you get the paint to hot, you could "bubble" it which will drastically reduce the life of the paint in that area. ALSO, if you use a rotary buffer, keep the side that you are buffing with to come off of edges. You do not want the buffer pad to catch on edges. It could rip the clear and paint off.

When you are done with compounding, the clear should be relatively... well... clear! LOL You should have an even reflection on the entire car, if you notice dull spots, go over them again. Then comes glazing the car. You use a finer buffer pad and this removes the scratches from the compound and its harsher pad. Then comes final glaze which is usually applied by hand and give the clear a little more luster because it removes very very fine scratches.

excellent write up...  i really wanted to go to wyotech but didnt want to leave home (hawaii). so i chose to stay here and take up autobody repair and paint here at a local community college... it ranked 3rd in the nation...

great info!!

yea i think this is a great writeup beacause i think if you have some skill and u follow these directions to the "T" you will do a good job no doubt. i talked to the guy who did this writeup and he sounds like he knows whats up. so use it ladies and gents....for i will.

i never went to school for painting...but from what i was told, every big production shop has thier SOP, standard operating procedures...especially shops that paint high end cars...somes painters follow it and some dont...but its a way to ensure quality control over their repairs...dupont needs it that way too to honor their life time warranty...
 
when painting completes, its important to have the right basemaker...especially with metallics...like you said, the flakes need fall in uniform...
 
i guess the norm would be 3 coats if you're painting the car the same color...the way i do it is, once you think you have full coverage, put one more coat on to be 100% positive...also, if there are primer areas, spray those areas first...
 
depending on what basemaker you use, you can sand within the first 10 minutes...if you're painting a complete...prolly more like 15-20...it mostly depends on the temp of the booth...and the areas that you did sand, you can burry them by misting 4-5 light coats...then blend out depending on the color...big metallics like the accord silver are harder to blend that say bmw's 354 because the size of the flake...the bigger the flake, the more room you need to blend...all other colors are usually not a problem...
 
when i paint a hood and/or roof, i start near to middle, walk around the other side then far to near...this way, the clear melts better...sometimes, especially older cars, i'll criss cross my clear to burry rubbish...less sanding...less buffing...its all about production...
 
if i spray a complete in the morning, i'll bake it for 15-20 minutes, i'll usually start buffing the top surfaces the same day...this all depends on the clear...some clears are thin and will stay soft...some clears are thick and once it's hard...the bugga is hard...if i'm the last to paint, i'll leave it over night and start buffing it after morning breakfast...you gotta find that 'sweet' spot when the clear is soft enough to sand and buff but not too soft as to where the scratches will come out again...a good way to tell is when wet sanding with 1500, if the clear sticks to the paper, its not ready to buff yet...
 
i usually knock my runs down with 800...if they are really bad, i'll hit it with 600...then 1500...you'll be there for a while with 1000...its very important that you BLOCK all runs...once you cut through the clear, you'll need to blend color in that area and reclear that panel...
 
depending on what compound you use and how long the car has been sitting, 1500 will come out no problem...make sure you get enough heat to let the compound work but dont burn the car...keep but buffer flat at all times...this will help with swirl marks...after your done buffing and depending on the color of the car, always finish with a foam pad and swirl mark remover...finish with a black pad on black cars...if not, you'll leave fine scratches...silver is a cake walk...wool pad is usually enough...foam pad if you want it really nice...
 
on black cars, don't go over 1800 rpm for buffing...1200 with foam pad...all over colors, i go 2200 for cutting, then 1400 foam...
 
good write up but i think all painters, if they've been doing it long enough have thier own system...lots of useful information nonetheless...
 
just adding my 2 cents :)

i went to uti for paint and this write up sounds good (details differ here and there), but body work/prep is what makes or brakes the finish. i hope this doesn't inspire too many people to jump off and just start spraying their cars. there would be a whole bunch of poor paint jobs.

This is a nice write up. 
 
I do have one question though, and I know this sounds silly, however I know nothing about this stuff.
 
Any way, at what point do you paint all the jams? Like door, trunk, hood etc.? Before or after the main body?
 
Thanks again for the info. Good stuff here.

before the body.

yea sorry guys i forgot to say in the begining this isnt my writeup it was from a guy i was talking to yesterday and i kno they differe from other ppls way of painting...because i thought of other methods that i was taught...but non the less i believe this was a solid writeup.

its amazing what info you can find nowadays. thanks for sharing this.

The hood and trunk jambs need to be painted before...those panels are usually on the car when spraying completes...the door jambs can be sprayed during or after...its actually better you spray during because you won't get a line or dry spray...it'll be nice and smooth...once a painter is in the booth, he/ she likes to knock everything out in one shot instead of painting the car...rip and the masking paper off, retape, scuff the jambs, spray color, clear and clean guns after

you can paint the doors and bumpers seperate...or just tape the doors so they can open and then shoot the jamb on your last coat...it really depends how much work you want to put into it...but when you spray kandy, you better make sure all panels are on the car...

The way I saw taught, and usually have seen it done on tv as well, is to paint the jams base/clear, then mask them off, shut the doors, sand the overspray and do the outside of the panels.

thats how i was taught too. using soft line tape so there wasn't a line. different strokes for different folks i guess.

Actually, doing the jambs last is probably easier to mask without lines, because if you mask the outside of the door, straight down past the edge, the line where the paint meets will be on the very edge of the door skin, pretty much completely invisible.

Mebbe I'll give it a try when I paint my car....

Great write up and a solid foundation to build on. We all develop our own styles after the basics. 

Do the jamb and trunk before the body. I wait a day and retape a mm into the jamb line with soft edge.  Ive tried a few ways and this seems to work best for me. I shoot Kandy and pearls  very well now. 
 
[CENTER][B]Sounds a LOT easier than it really is, but anything can be done with lots of practice.[/B] [/CENTER]
 
I would do this for a living if i could make money at it...or make enough money (@ my day job) to retire and just work on cars. 
 
We all gotta dream right?? :smiley:

how r you guys and gal, shoot'n the side door mirrors?  

do you keep'em on the door, take'em off, take'em off then disassemble the housing parts and paint the little parts individually, etc..

On my car, I had them off during the painting of the car, and painted them off the car, just masked off the mechanisms and mirror.

At work we masked around them.

If I were doing a car for myself though, I'd take them off most likely...all the mouldings and trims that most cars have make it a real bitch to mask around mirrors really well.

Take them off. 
 
I dont like seeing taped headlights,taillights,etc,etc....
The more parts that come off shows the level of work they're willing to do on your car. :biggthumpup: 
 
 
 
Ive hung doors,hoods,mirrors,trunks, even stripped interiors to document paint jobs for resale.

honestly since i never painted for a living or got into candys, i prefer panel painting (painting as much as you can off the car).

Always take the mirrors off...very easy to do...just take off the door panel and its usually 3 10mm bolts...some cars no need take door panel off...if you don't take them off, you risk the chance of getting dry spray below the mirrors...that and you always want to take the window molding off and to do that, the mirrors need to be off first...

If you don't put all the panels on the car when shooting candy, you'll have dark and light areas...its not like shooting metallics or solids...you need to walk the car ensuring the whole car gets exactly the same amounts of coats...candy is transparent to the more coats, the darker the candy...and usually candy is a 70% overlap, not 50%

at school, at the body shop i used to work at, and projects of my own, we/i spray the jambs first, imo, not trying to knock others just my opinion and experiences, spraying the jambs after the car is painted, you run the risk of getting overspay over the whole car if not taped up properly. spraying the jambs at the same time as the car is cool cuz it looks like it came from the factory painted, which means the doors are off the car, if your spraying techniques isnt the car from body to door, its possible for the color to be off, then itll look like you touched up the door or something. anyways, the spray the jambs first then the whole car. youll have a line where you tape off the jamb but if taped properly/not a solid line (reverse tape or foam tape, you can compound that blend line/dry spray out and you wouldnt even know... but to me, if you got a line in the jamb where you taped off, its not that bad, its not like youre gonna show off your door jamb to the public or something....

its also like, say you paint both sides of the jambs (body side and door side) just the jambs and not the exterior, you can start to put small things back together in the jambs, and say by some unlucky chance while reinstalling the door you accidentally scratch the outside you can still go back and fix it, or while final fitting the door you nick the corner or something to that nature you can still go back and fix that problem area. where as if you spray the doors off the car, you gotta be EXTRA careful when reinstalling the door, being sure not to scratch the outside, corners, etc... with me, painting the jambs first is easier, when bolting the doors back on, i can do a final fit of everything one time and one time only, and not have to worry about it again. also too, depending how the jamb area is designed or made, you can hide your cut off lines, like behind a weather strip, or molding, etc...

if you are say, painting tri stage (base, mid coat, clear coat) and you got your hood, doors on stands, and you spray everything, most likely one of your panels isnt gonna match the rest of the car. somewhere along the line you spraying technique is gonna change, you might accidentally made one more past or pearl over a door and not the other, or you might have a build up of pearl on the edge of the door, and when you install it next to the fender the colors dont match up... get what in saying? but if you installed the hood back on the car, doors back on the car and spray the whole car, walk the whole car during pearl, and clear it, you'll have blended each coat of base, and pearl to each other so that to the eye, you wont be able to see any discoloration... 

heres some pics of when i painted my friends 350Z... did the jambs first, then the car, compounded the jamb area where i taped off, never hard line... you can see in this first picture the cut off line isnt a hard line, its kind of feathered or blended.
[IMG]http://i22.photobucket.com/albums/b335/calitri808/IMGP2105.jpg[/IMG]
[IMG]http://i22.photobucket.com/albums/b335/calitri808/IMGP2102.jpg[/IMG]
[IMG]http://i22.photobucket.com/albums/b335/calitri808/IMGP2100.jpg[/IMG]
[IMG]http://i22.photobucket.com/albums/b335/calitri808/IMGP2099.jpg[/IMG]
[IMG]http://i22.photobucket.com/albums/b335/calitri808/IMGP2097.jpg[/IMG]
[IMG]http://i22.photobucket.com/albums/b335/calitri808/cory%20car/ray010.jpg[/IMG]
[IMG]http://i22.photobucket.com/albums/b335/calitri808/cory%20car/ray011.jpg[/IMG]
[IMG]http://i22.photobucket.com/albums/b335/calitri808/cory%20car/ray008.jpg[/IMG]
my thing is, if it can be taken off to paint, take it off...
great additions guys to a great write up....

Whats going on guys? My name is Josh Helfrich and I put together this write up. Prior to WyoTech I had no idea what I was doing and the paintjob I actually did before WyoTech was OUTSIDE in the sun at like 85* F... LOL. Its easy to say that the primer was rough from drying too fast and even before it got to the surface of the car. As any of you know, cars get hot in the sun... mine did too.
 
But hey, we can only learn from our mistakes... and I sure did.

nothing wrong with painting in 85* weather...our booth stays constant at about that temp...the primer was rough because you probably used the wrong activator...do you still paint?
 
if we do paint the car with the doors off, we always take precautions when putting everything back...tape edges, tape corners, floor jack under the doors, etc...but accidents do happen i guess...
 
i tihnk all jambs and owners are different...a few examples...
 
the jeep jamb line is offset about 2-3 inches...most cars are about 1/2"- 3/4"...you ALWAYS back tape the jamb line...so needless to say, the jeep had HEAVY dry spray...all i did was ran used 1500 over the area a couple times and buff it out with my 3" buffer...it was still a little rough and by no means oem finish but it was a jeep...
 
some mercedes and bmw owners are extremely pickey...they run their fingers along the edges so there must be absolutely no line and no hint of dry spray...on those kinds of cars, sand the jamb just inside the jamb line and i'll explain why i do that later...i then back tape the jamb line which is about 1/2" offset...tape up all the doors so they can open...its a little more taping but you don't wanna get caught with an anal owner (it's double work if you need to paint/clear the jamb after everything is buffed and polished)...so after you base the car and shoot the last coat of clear, cut down the air pressure to reduce overspray and pull the tape back a little bit then pass over the jamb once...
 
thats why you sand a little past the line...when you spray with the doors closed, color obviously gets inside the jamb up to the tape line...if you were to clear it without pulling the tape back a little bit, especially with metallics, you'll see a nasty cut off line where the color and clear stops...so when you pull the tape back, you have a little buffer zone where the clear is past all the color and make it impossible to see anything...and after you clear the jamb, pull all the paper off then pass it with some clearcoat blender to melt the edge...
 
hope all this makes sense...kinda hard to explain...

[quote=VIP-UCF;107011]nothing wrong with painting in 85* weather...our booth stays constant at about that temp...the primer was rough because you probably used the wrong activator...do you still paint?
 
[/quote]
 
I know that there is nothing wrong with painting in an area that is 85*... but painting OUTSIDE when its 85* and in direct sunlight... there is the problem. That is what I did my 1st paintjob because I didnt know any better...