Can you use too much water when wetsanding with a DA?

[Mark Preus]

Just curious on wetsanding with a DA. I noticed that sometimes I would have little swooping lines that were real hard to buff out from sanding with the DA. I assumed a piece of dirt or something was on the surface and thats what caused this. So here lately im always nervous and tend to spray on alot of water while doing this. Can it be possible to have to much water and the DA can not sand as good as its suppossed to? Any advise would be appreciated. Mark

[ASPHALT ROCKET]

Sounds like you had a piece of debris under the paper and that is what caused you pigtails. You can not have too much water, it is going to be kicked out by the motion and the weight of the sander. I prefer to ad a few drops of dish liquid to my wet sanding water. Also this is why I prefer to wet sand by hand, you can feel and hear the little squeal noise from the debris while sanding. this way you can stop alot quicker and not have any surprises like you do with a da.

[David Fermani]

If you have ANY debris caught in you disk, you'll have marks all over your paint. I've been doing alot of wetsanding with my DA lately (and love it!!). I try keeping speeds atabout 3-3.5. If you're new to DA sanding, I suggest buying a 3M interface like these: 3Mâ„¢ Hookitâ„¢ II Soft Interface Disc Pad, 05273, 5 in, 10 per case

I've been having great luck using a light mix of ONR. It's adds a touch of lubricity, doesn't dry like straight water and extends sanding times.

Those "swooping lines" are called "curley ques" or "pigtails" and they usually occur from not keeping the face of the sandpaper/DA flat. The interface will help eliminate this a little. Make sure to start and stop your machine on the car. Don't have it moving one bit with it not 100% fully on the paint. If you do, the edge of the sanding disk will dig into the paint causing these sometimes deep scratches to occur.

I strongly suggest using 3M's Trizact 1500 and 3000 disks. They greatly reduce curley ques, last longer that other sandpapers and finish very uniform.

I'm sure Mike Phillips will chime in on this thread to give his analysis of the situation and strongly caution using an electic DA with or anywhere near water. In 3, 2, 1.....

[David Fermani]

Oh, I forgot to mention. Too much water will cause your disk to hydroplane and you'll decrease your cutting action/performance.

I suggest watching this very informative video:
Logging in

Pay close attention to the 2 & 3:20 minute mark.

[Mark Preus]

Im not using a electric DA im using a Dynabrade thats airpowered. I also use the trizac disc and interface pad

[David Fermani]

That won't make much, if any difference then...Same technique, different feel.