Wet sanding instructions

JDookie · 05-23-04, 08:38

Okay, I'd like to start a discussion on wet sanding. This is a method that is used by a few and feared by most. I am looking into it because I recently had to get a corner of my rear bumper touched up after a little mishap with my own gate and it now has a little orange peel that it never had before.

What determines what grit to use? What's the best way to actually sand the desired area? By hand or use a block of some sort? Will a PC with the right products be able to polish it to a shine afterwards? (The strongest product I have is 1Z UPP)

I have wanted to try wet sanding many times before but was always afraid to, so load me up with info guys as I'm sure everyone in the same boat as myself will appreciate it.

destair · 05-24-04, 03:18

I've delved a bit into the "wet sanding zone." I had some medium (could be felt with the fingernail) scratches on my 2002 fire red Dodge Avenger. The products I used, 3mPI-II compound being the most abrasive, weren't getting it done, even with my PC. So I bravely, or perhaps foolishly, got some 2000 sandpaper, a foam block and some soapy water, and jumped in. I'd sand a little, ten strokes or so, VERY LIGHTLY, wipe away the water, check for progress, and continue. It wasn't long before I saw the scratch disappear. I then got my PC and a bit of 3mPI-II and set to work removing the sanding marks. They disappeared nicely and I followed with polish. The scratch is gone.
Maybe I had some beginner's luck. What I'd recommend is practice on a spare hood or fender procured from a junk yard or body shop. I have a red fender that I am practicing on with my PC. I tape it off into four different sections and practice not only wet or color sanding, but I also try different product combinations. I leave the fender out in the elements and compare the sections for beading, fading. etc.
Just a suggestion, but I don't think you can ever go wrong with practice.

Darryl

"Average technique+great products=average results
"Great technique+average products=great results
"Great technique+great products=super results!"

JDookie · 05-24-04, 03:25

Thank you for the reply. It sounds pretty basic and I would assume that as long as you don't apply too much pressure and/or sand in one area for too long you would be okay.

When wet sanding, do you always sand in the same direction? I would think the obvious answer is, yes, but I'm going to ask anyway.

You said that you used soapy water, is that the best way or would just plain water be better? Would maybe QD be even better than soapy water for the added lubricant?

As you can see, I still have a few more questions. Hopefully, we can get a few more people to voice their opinions and expriences like you did.

snake2 · 05-24-04, 08:10

I found the following thread very helpful. I think i'm ready to try this now. Give it a look.
http://www.bimmerfest.com/forums/showthread.php?t=32625

theveed · 05-25-04, 09:49

Oh, tip I can give you is to NEVER underestimate the importance of soaking the sandpaper thoroughly before using. Always buy high quality paper as some paper may claim 2000 grit or finer, but they have one or two grits that are courser causing little scratches that can be very difficult to remove.

In my opinion, nothing's more fun than wetsanding an old car with beaten up paint then buffing it to a show car finish hehe.

TOGWT · 05-26-04, 04:16

~One man’s opinion / observations ~

Wet sanding:
For light scuff marring on the paint film surface that cannot be removed with an abrasive compound (like Meguire’s ™ Duel Action Cleaner Polish) Soak some 3M™ s #2000 and #2500 grit paper overnight in car wash concentrate solution, then using 5:1 Woolite / Distilled Water solution in a spray bottle as lube, using the rotary attach the # 2000 grit Velcro backing to the rotary disc, at 1100 rpm this should minimize the scuff / marring, then move onto the #2500 grit which will probably leave a haze on the paint. Use a (Meguire’s™ #2) Fine Cut Machine polish using a firm pressure on a foam pad; then go to Meguire’s™ Duel Action Cleaner Polish, then a Swirl Mark Remover (Meguire’s #9) finally apply a protecterant. The scuffmarks /marring should be cleared from the paint surface.

~Hope this helps~

Experience unshared; is knowledge wasted…/ Jon
justadumbarchitect *so I question everything*

qwik · 05-26-04, 05:44

i wouldn't even attemp this w/o the use of a rotary. I used meguiars unigrit 2000 grit when i removed some of my orange peel. I prepared a bucket and soaked the sand paper 15 or so minutes (even overnight sometimes) prior to working. I put a bit of carwash soap to help with lubricity and keep the paper from clogging up. You sand back and forth with light pressure in even strokes. Use a squeegee to check your progress. I used heavy/medium/fine cut compound but i was supposed to use diamond cut/compound power cleaner/dacp. Or just diamond and dacp. I would recommend that instead since that is what meguiars personally recommended to me. If you goto google and type in "wet sanding" you'll get some hits with walkthroughs with pictures.

Jimmy Buffit · 06-08-04, 03:36

Just remember how thin the clearcoat is.

That's all I'm saying.

Rookies should proceed VERY carefully.

Jim

JDookie · 06-08-04, 04:33

Oh, I know. I'm not even attempting this on my vehicle until I practice on a fender or something I can get from the junk yard. Right now, I'm still trying to track down some 3k grit paper. All I can find is 2k and that's too aggressive for me. Who sells it on the net??

Spilchy · 06-08-04, 04:37

Quote:

Originally posted by jimamary
Just remember how thin the clearcoat is.

That's all I'm saying.

Rookies should proceed VERY carefully.

Jim

I have never wet sanded. Given the nature of the task I am a little nrevous to tackle the job since I have nothing to practice with.

My question and confusion is as follows: If you wet sand clearcoat, follow with Diamond Cut, Compound Cleaner then DACP all with a ROTARY and some with a WOOL pad, how do you NOT burn through that portion of the clearcoat?! How much do you affect the integrity of the clear?

I admire those select few who have the ability to TRULY buff out a car to a flawless finish.

Spilchy · 06-08-04, 04:57

Nice article to read:

http://www.moderncarcare.com/Articles/261deta1.html

6318 · 06-09-04, 08:38

Quote:

My question and confusion is as follows: If you wet sand clearcoat, follow with Diamond Cut, Compound Cleaner then DACP all with a ROTARY and some with a WOOL pad, how do you NOT burn through that portion of the clearcoat?! How much do you affect the integrity of the clear?

good question
I don't generally wetsand a factory paintjob just to remove orange peel since the clearcoat can be so thin...
I use this technique on a custom paintjob where paint and clearcoat are thicker