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dbgriffith75
I don't have anything in particular I'll need to wet sand soon, but I got to thinking about this today and was just wondering.

I've known some people to spray a given area with a hose, then sand.

I've known some to wipe down the area with a wet rag, then sand.

And one guy I know dips the sandpaper in water, then sands.

My personal preference is to wipe down the area with a wet rag, then sand. Just wondering how other guys do it and what could be considered the "best method."
beerchug.gif

PanelBilly
Soak paper in clean warm water for 10-15 minutes. Get a spray bottle and spray with one hand while you sand with the other.
biosurfer1
Do NOT use your hand to apply the sandpaper, get a dense foam block.
sww914
If it's outside and it's warm I'll use a hose. If it's inside and I don't want a river running through the shop I use a bucket and a rag. If it's just a couple little spots I just dip the paper in a bucket here & there. You can use your hand if you're careful about not making high & low stripes with your fingers, if there's any doubt use a foam block. I always sand the bodylines, edges, and depressions first and then do the flats. That will smooth out any ridges that you made while concentrating on the little surface features.
76-914
From a guy who decided to paint his own plane and had to wet sand the entire clear coat job, take it from me. I like to keep a bucket of water with a few drops of dish soap, a hose for fresh water and pads. Depending on the surface you will need firm and soft backer pads. Keep your paper in the bucket when not using it. They'll keep for days in water. BTW the soap is a lubricant. Remember your actually cutting and the soap helps lubricate. (glycerine?) Whatever your sanding/polishing, you will need to take it up in graduated steps. Your wet/dry grit commonly runs in 800 - 2000 range. Jobber auto paint stores usually have all of this stuff and yes they will sell to you.
charliew
All the above. The idea is to keep the paint from building up on the paper and scratching the surface. The fresher the paint the easier it will happen. You can feel it when it happens and the scratch is a mess to get out. You can never have too much water but you can also use less if you pay attention. I never use my bare fingers on any surface that is flat. Your fingers will never make a surface flat, I only use my fingers on edges. I usually only go in the same direction about 5 strokes, I go in circular, 45, 90 and 90 to that strokes. I use a bucket for small areas and a old bath towel to wipe up to check my progress. I usually use a stikit 3m yellow foam pad that is shaped like your palm on the top. I use it either direction though. I think it's a 3m product but it's been around a long time and lasts a ling time. I also use several different size dense rubber pads. If I'm doing tight inside curves I use a curved pad. I've been wetsanding for almost 50 years and my sanding muscles never tireout but this year my shoulder has started poping but it doesn't hurt or get sore. A lot of the pros are using a dry sanding system that has as high as a 3000 grit. it costs about 300.00 just to get started with it but they say a package of pads lasts a long time. I have some pretty expensive paint tools but that won't be one I think I will need.
effutuo101
good advice. The only thing I have done different is to have a sponge that I dip in the water and keep close to where I am working to add water to the sanding. The spray bottle seems like a much cleaner idea.
dw914er
QUOTE(sww914 @ May 12 2009, 08:09 PM) *

If it's outside and it's warm I'll use a hose. If it's inside and I don't want a river running through the shop I use a bucket and a rag. If it's just a couple little spots I just dip the paper in a bucket here & there. You can use your hand if you're careful about not making high & low stripes with your fingers, if there's any doubt use a foam block. I always sand the bodylines, edges, and depressions first and then do the flats. That will smooth out any ridges that you made while concentrating on the little surface features.

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(he taught me btw, and I used a foam block because it just made it alot easier since I was/am a n00b)
TeenerTim
I do it in the rain. A nice steady summer rain is best. Put on your swim suit, turn up the tunes, and get busy. The work goes very quickly. Now that I'm thinking about it you could turn on the lawn sprinklers... idea.gif
Jeffs9146
A friend of mine spent the summer when we were younger wet sanding a bug with a block and lots of beer! We had a left over keg with only a pump so it was going to go bad. He filled up his cup and drank a sip each time he dumped a sip!! Then rinsed the car with water when he was done.

His girlfriend ended up beating the paint with a spiked shoe and it didn't even chip it!! beerchug.gif
7TPorsh
Never sand in circles!!! Cross hatch in an X pattern and move side to side. Watch the edges.
Phoenix-MN
agree.gif with all of the above and add this:

Start color sanding with 1000, after a little sanding completely dry off the area, the orange peal low spots will still shine and the high spots will be dulled. When there is just a liittle shine left switch to 1500 and repeat until almost all of the shine is gone. Then switch to 2000 and finish the job. After final machine buffing it will be smooth as a babys butt.

Paul
jmill
Use 3M paper. I've never had a problem with it. Soak it first.

As far as water I like to rig up my own water system. Buy some 1/2 white pvc pipe. Cut a piece about 3' long and drill 1/8 holes in it down the pipe about an inch apart, all in a line. Glue a cap on one end and a hose fitting to the other. Not the threaded one. Get the fitting that plugs into the inside of the hose. That way there's no metal to scratch the paint. Get a couple of suction cups and attach them to the pvc pipe. You now can place the pvc sprinkler anywhere on your car and have constant fresh water. You can buy a setup like this but why when you can make it for less than $10.
charliew
I really don't use that much water you just need to keep the residue flushed out from under the paper. A squirt bottle is all I need or a sponge. Also not much pressure but keep the pad flat.
Porsche Rescue
Just did some wet sanding yesterday after touching up some scratches by hand. You MUST use a sanding block. I like the 3M rubber block that takes a 1/4 sheet of paper. I used a squirt bottle with a few drops of liquid dish soap. Squirt/sand/dry with a rag and look at my work...repeat. The advice above about looking at the orange peel is important. I used 600 (very carefully), then 1000, then 1500, then buff.
I have used a bucket of water to dip sanding block in (indoors) and hose (outdoors) and I think the spray bottle is best. Enough water, easy to control, little mess, and it keeps the paper cleaner than the other methods. I wipe the paper with the rag at the same time I wipe the car.
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