Wet sanding - PeachParts Mercedes-Benz Forum

greasybenz · #1 12-27-2005, 11:37 PM

Has anyone ever used this? My dad said he saw it on two guys garage and picked it up at home depot. He said its supposed to shine old paint thats faded. He used it on a ford ranger before he sold it and it did shine it up (so he says) never actually saw the car after he sanded it and sold it.

Your supposed to wet the car and then sand it and the old paint will shine like new. My SD isnt very shiny since it has the old paint and its raining outside so when it stops ill take the car inside and try this stuff out see if there is a difference.

Angel · #2 12-28-2005, 12:17 AM

hmm...my understanding is this...my numbers may be off a bit:

Sandpaper (which is pictured) is simply an abrasive that smooths the surface of the paint when you sand it. Wet-sandpaper is just sanding grits on a paper that doesnt come apart after it gets wet.
You make the car wet becuase sandpaper has a tendancy to "load up" -this is when little paint/dirt/dust/junk pieces fill in the spaces between the grits on the sandpaper. When all the little spaces are filled, the sandpaper doesnt sand anymore. With wet-sandind The water carries away dirt and paint pieces that would otherwise get gunked up inside the sandpaper - so it lasts longer. I would expect to use more than one sheet when wet-sanding an entire car. Pro's keep a steady dribble of water flowing over the wet-sanding paper to keep the paint/dirt/crud flowing away (but that dumps a lot of water on the ground.

There are some important things to remember. Any sanding using any grit sandpaper removes material forever - be that dirt, ugly paint or good paint - you dont want to remove good paint =) A car with good paint shouldnt be wet-sanded **repeatedly** (unless you are planning to add more paint (IE re-paint the car). Some may say that you should never wet-sand a car that has useable paint. There are "abrasive" or "paint cleaning" waxes that do the same thing. I wouldnt wet-sand my 240D, the "paint cleaning" buffing compound (sold by various companies, Mothers, Meguires...) will clean my paint nicely (when I get around to it)

My other concern is this - 600 grit is pretty abrasive for a car that has a decent finish on it. They make 1200 and 2400 grit paper - you might have to look in an automotive store - I'd try the 1200 stuff first - you really dont want to take more paint off than you need. Others may correct me on this. OR If you are selling the car, you might not care how thick the paint is on it...

Free advice, worth what you paid =)

davestlouis · #3 12-28-2005, 12:18 AM

whoa.........do yourself and your car a favor, let a professional buff the car, don't try color-sanding a car unless you want to need a paint job post-haste. The shop where I work would color-sand a car to remove dirt nibs from the fresh finish and level off orange peel, but would never dream of sanding an existing finish...who knoew how much paint is there? how hard is it? is it thin along character lines and such? And 600 is too coarse...2000 would be more like it if you insist on taking a stab at this.

greasybenz · #4 12-28-2005, 12:36 AM

Well ill try it out anyway, were planning on getting the car repainted anyway so if i mess it up no big deal. Its just that the paint on my car is faded and not shiny so if this shines it up or makes it look any worse then it already is ill just go ahead and get it repainted.

If i do repaint it its going to be a smoke grey with the original grey at the bottom or a dark maroon with a beige bottom.

JimmyL · #5 12-28-2005, 12:43 AM

Good info boys, and a nice try. Some folks are gonna do what they're gonna do, regardless.
Two-tone?????

greasybenz · #6 12-28-2005, 12:48 AM

Quote:

Originally Posted by JimmyL

Good info boys, and a nice try. Some folks are gonna do what they're gonna do, regardless.
Two-tone?????

The car is already two tone white ontop and grey at the bottom. OEM color combo. So why not smoke grey at top and original at bottom? And as for the sanding well even if they told me those things im only trying it because i know if i mess up the original paint it doesnt really matter its getting repainted later.

greasybenz · #7 12-28-2005, 12:51 AM

This kind of paint combo is just beautiful on a W126

JimmyL · #8 12-28-2005, 12:55 AM

Quote:

Originally Posted by greasybenz

The car is already two tone white ontop and grey at the bottom. OEM color combo. So why not smoke grey at top and original at bottom?

Whoops, for some reason I had 240 on the brain. Too many threads, too little gray matter.

I would recommend the polishing compounds as suggested as opposed to the sand paper. No rush to pay for a paint job, right?

greasybenz · #9 12-28-2005, 01:00 AM

I tried waxing it before but it was the same thing. But if that polish compound stuff works i guess its worth a shot but id rather just save the cash and wait to get the car repainted to either one of the color combos.

thanks for the advice

Ra_ · #10 12-28-2005, 08:32 AM

If the compound works, you'll save the expense and hassle of a paint job.
I wouldn't be so quick to dismiss the idea.

I've seen it bring back some very faded old cars.
Remember that it will still look a little dull, until you apply some wax over the reconditioned finish.

If you paint a car a 'new' color,
you have the added hassles of having to paint all the door jambs,
under the hood, etc. etc. , otherwise it looks pretty odd.

Oilbrnr · #11 12-28-2005, 08:53 AM

Quote:

Originally Posted by greasybenz

The car is already two tone white ontop and grey at the bottom. OEM color combo. So why not smoke grey at top and original at bottom? And as for the sanding well even if they told me those things im only trying it because i know if i mess up the original paint it doesnt really matter its getting repainted later.

I'd stick with OEM paint scheme. Color changes, done correctly, are very $$$. White door jams and under hood trunk areas against grey would look a bit tacky IMHO.

As others have said above, you are just going to make a mess of the paint, and dull it up more with 600. Why do you need a repaint on a white car, is there other paint damage other than being 'dull'?

leathermang · #12 12-28-2005, 10:15 AM

I am with Ra and those saying use polishing compound...
this is typically white ...
there is also Rubbing Compound... usually red... which takes off more...
Try the Polishing Compound first...

600 grit wet and dry was what I used before the last paint ... but after the last paint was applied then only compounds would be used...
although it is perfectly acceptable to use that compound on cheesecloth with something backing it... like a paint stirring stick... and use it in the same direction... with the long axis held steady and the strokes in the diagonal...same as you would when getting bondo or spot puttin back down to proper level using what is there but on a curve... It can really make a flat polished surface.. but arm work is much harder than a good electric or air polisher.... but care must be used as a slight mistake can burn a spot....

Mismost · #13 12-28-2005, 10:28 AM

Polishing Compound....is the frist thing to try...be aware, this stuff "loads up" too, so use lots of clean rags and/or rinse out your polishing pad. Work in the shade, small areas at a time, wipe it off often. Red is for Rougher finishes, the white is for pretty good finishes. Polish out, wash up, wax down...if you have any paint at all on the car, it'll shine, glitter, and gleam. Low cost, high effort project.

Smokiesman · #14 12-28-2005, 10:45 AM

I use a 3 step process when I do my cars ! I use a medium to heavy duty liquid rubbing compound ! Don't get nuts with it though and burn your paint. Do small areas and run buffer on LOW speed ! I then use the 3M swirl remover to really bring up the shine! again buffer LOW speed. I top it off with a coat of Zymol and she will shine like a new penny!

Do not use that 600 grit paper ! Nice for polishing bare steel but will rip up your paint!

Smokie

Diesel Giant · #15 12-28-2005, 10:56 AM

You sand with 600 and your going to be taking your car to the paint guy to repaint it. Wet sanding is usually done with 1200-1500 grit and a buffer. I would get a compound buffer and some good buffing compound.