Sprayed my cowl, now want to wet sand a finish....

use the low pressure water hose and put it on the cowling to let the water flow on it. Then sand with "560 grits or more wet sanding paper" and sand it slowly with flowing water until it smooth it out.

this is what I have done and works great.

but I'm not a high quality expert wet sanding

 

http://www.hotrod.com/techarticles/body/hrdp_0805_color_sanding/index.html

 

start with maybe  400 -600 grit and work your way up then buff to a mirror shine, if you rub to hard you'll burn thru the clear and then your back to the spray booth  . edges and corners are usually the first places you'll burn thru  so pay close attention to these areas and absolutely keep the water flowing on it as this washes the sanded paint off and keeps the paper clear. good luck 

 

You guys are insane.
Don't use anything less than 1000 grit, and that's pushing it.
Let the paper do the sanding, don't force it.
Stay away from edges unless you're an experienced buffer.
If you decide to want to buff out the edges, make sure you use slow speed and work it so the pad is ridding off the edge, not onto the edge.



I'd advise 1200 grit, 1500 grit and possibly 2000 grit.
It all depends on the grit compound you are going to be using.

Remember, I'm a professional.



Get a water bottle.
Put a drop or two of dish washing liquid in the bottle, then fill with water.
Pop a hole on the cap using a phillip head screw driver.
Use it as a squirt/drip bottle as you sand.
A water hose can get real messy!

Grab either 1000 grit or 1200 grit on a wet sanding block and block it down to get rid of any orange peel or imperfections.
Be careful you don't burn through.
This step is what gives it the shine.
The flatter it is, the more shine it'll have.
Once done, get the next grit which ever case being.
Do the same, but you're not worried on knocking out anything, rather than just polishing away the sanding scratches left by the previous grit.
Continue till you're happy.
Bright colors are good to go with 1500, some 1200 depending on the compound used.
But if I'm doing black, it DEFINITELY needs to be at 2000 if wanted flawless.

Buff at a slow pace with no real pressure on the buffer.
Let the machine dig the compound into the surface.
I use a wool pad, but one can use a foam pad(if using the foam pad, make sure it's the yellow compound pad).
Remember, let the machine do the work.
People get swirl marks from trying to buff fast and hard.
Once it's completely compounded, it should look good, but lack depth.
Grab a 3m black foam glaze pad along with a bottle of 3m foam pad glaze and polish it out.
Once done, it'll look like glass.
A perfect mirror finish.


I don't know how more descriptive one can get when it comes to this unless I was to tell you exact RPM to spin the machine.
Which I don't know, I just do what feels right.
I know my buffer is usually set between 4 and 6 while compounding, and 3 while glazing.


Hope this helps.

-Eric

 

You might be a professional, but I stayed at a Holiday Inn last night

My advice...send it to Eric and let him do it...I am just too lazy.

 

lol...

 

Probably    [smiley=happy.gif]  Not that there's anything wrong with that.

 

Lol, I'm actually buffing a 40' boat right now...

Gelcoat is a different story. One can buff out 800 grit without a problem but on clear coat, it's a pain in the ass. Especially if it's black.

 

ok so i'm a little heavy on my paper ;D but the soap in a bottle is a trick i never heard of i use to work for a wrecker company in delray years ago that also had a body shop and got tips and info from the painter that worked there but of course none of my paint projects have required a mirror finish which leads me to a funny story about painting the fin & feather but thats a topic for a different thread ;D

 

The soap helps cut the clear quicker while keeping the sandpaper from clogging, and it leaves a clean surface. Lol

Since the first day I ever worked at a shop they always told me to use soap as a sanding aid.
Don't over do it and put too much, one just wants a bit to slick it out some.

 

Excellent Post IMHO. [smiley=1-thumbsup1.gif] You even ave up the soap secret.