can anyone give me a rough estimate of the final thickness of a base/clear paint job? Say, 3-4 coats of color and 3-4 of clear. The front door gap on my '51 plym is a little closer than Id like as it swings over the fenders edge and im wondering how much I have to worry. jeff
That is a tough question i know it could be between 4.5 to 5.5 mils it all depends on you gun set up how heavy you spray depends on how much primer is on the car from the factory specs can be between 4.5 to 4.8 in certain areas that would be from bare metal all the way up to top coat. If i were going to buff which i hate the total amount of clear over base for uv protection is 2.5 mils on top of base coat. I would always put extra coats on if i were going to wet sand adnd buff.
It just depends on How you spray! I get to the final primer stage and check my gaps! I put a lot of material on when I paint! But I also buff everything! When I was in the collision shop we didn't gauge it either! Takes the fun out of it. It also depends on what gap you desire!!
Base coats are much thinner than clear coats and the gap edges can be sanded easily but very carefully.
Thinnest painting ever see on modern cars (I meter them all the time at work) is about 2.5-3.0 mils. Some Chryslers are 7.0+, Jaguars also tend to have rather thick paint, as much as 8 mils.
Maybe the issue is the door and fender need to be readjusted to get them right? Not worrying about the paint?
I think looking at the overall gap and setting it were the least amount of fixing is needed. Make something like a gauge to adjust!
4-7mm is a lot of paint! Average modern car has approx 120 microns (1.5-2mm) from electrocoat to clearcoat. Most basecoat colour takes about 2-3 coats to reach opacity and apart from maybe a pattern coat for pearls or flake then that's all you need to achieve. 2k clears are usually a 2 coat system, you can then fine sand and flowcoat with 2 more. Acrylic lacquer clears are usually 4 coats thru a 1.8-2mm set up to be able to fine sand and polish. Too much build with acrylic lacquers can cause probs later.
I know this is wrong.but ive painted cars and bikes for 40 yrs and to this day ive never even thought about how thick I should put it on there.we just shoot it until we are pretty sure that with color sanding and buffing it will still be there. I really would like to know just how much we put on one.i know how much we take off when we color sand..ALOT!!.I DO KNOW THAT IN ALL THAT TIME IVE HAD 3 CARS THAT WENT WRONG..damn cap locks. anyway ive had 2 come back because of paint getting thin or seemed to, to them. I have sanded thru on jams a time or 2,but not much more. and that was my fault.seems drinkin and sanding just don't mix to well...
I'd guess if the gap is so close you're worried about paint thickness, then it needs to be fixed before paint! Considering a heavy BC-CC paint job is maybe 10 mil.
I appreciate all the help, it looks like the general consensus is less than 10 mil (or better known as .010"). If that's the case, Ill be fine. I kept my original question real simple w/out alot of details just to get a simple basic answer My primer is all set and so are the gaps, so All I was curious about was the color and clear build up. My doors swing out and over a tight radius when they open so the gap changes a lot as it opens. Pics are worth a thousand words: Here you can see the gaps are nice and even (front to back and top to bottom) Then w/ the door just starting to open, you can see the potential tight spot if paint build up is huge. Feel free to add any more insight to this since I love to learn. Jeff
you should allways set your gaps at 1/4" during the build stage so when the primer,color,clear stack up is all done you will have the right gap size plus the wider they are ,the less chance of hitting...
1/4" !!!! Did you look at the pics? If I gapped the front at 1/4" the doors would overhang the qtrs. like a model A , LOL!
Man those gaps look tight right from the get go. I have always heard you should gap about the width of a paint stick.
You guys are on the right track. And yes a mil is different than a mm. Don't forget there will be paint buildup on BOTH sides of the gap to contend with. Many mid 50's cars had a factory tolerance of 1/8" to 3/8" as acceptable when new. Personally, I have some 1/8" gaps that are a little tighter than I like after all paint materials have been applied. Posted using the Full Custom H.A.M.B. App!
i guess it is to late now, but the fender should have moved to the front and the door with it , way back when is was still in bare steel. now you are prolly screwed ???
naw, far from screwed, just need to keep a close eye on it while painting. And id much rather have a tight gap to keep in check once than a huge unsightly one. Plus, the gap w/ the door closed is the width of a 1/8" paint stick, thats how I set them. Its only close in a small portion of its opening arc (as seen in the pic). jeff
Here's a couple examples I've found: GM liked to see gaps of 3/16" on doors, and 1/8" on hoods and decklids on muscle-era cars (from a 1968 Olds Cutlass factory assembly manual). BMW specifies a panel gap of 4 millimeters (from a factory service bulletin). These specs are after paint. But let's say you set all your panel gaps at .1875" (3/16") in bare metal, with .010" paint thickness, your gap goes to .1675", which will be fine. In other words, your total paint thickness (both panels combined) is less than 1/64".
If there's that much concern some careful file work might open em up just enough, and another benefit would be a nice rough finish just on the part you can't see which will hold color/clear a lot better. From what I was seeing I'd worry more about driving over uneven terrain and the body/frame flexing enough to make contact.
Not sure why the doors would overhang by widening the gap, unless you moved the doors out to get that 1/4" gap? If you moved the fender forward to get it, the surfaces would remain even, not overhang.
I think you'll be fine. You may have 4 coats of clear on the fender but the edges and door jams should only see a coat or two.
also, you may be able to shim the hinges off of the body and adjust them back in on the door to get the fulcrum out further so the door swings away. I'm not familiar with your car's style of hinge and mounting though...
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