Wet sanding with a DA?

[showtime]

I do work for a car stealership that just hired an in house painter. On all the panels he paints I notice a ton of small U shaped scratches. I've been trying to figure out how they got in there like that because they're too small to be swirl marks, which he also leaves. It seems like he uses a DA and a harsh grit sand paper to remove orange peel. The scratches are just too deep to be caused by anything else. Am I right?

This seems like a good way of reducing OP if used properly. Is this what the Mirka system is? I've read about it but haven't seen any pictures.

[Mike Phillips]

Sounds like he doesn't' have a system dialed in for turning out quality work? D.A. Sanding is a great way to remove orange peel but it's important to use the right papers and then use a system of pads, compounds and polishes to remove the sanding marks while leaving a swirl free finish.

[the other pc]

The Mirka system uses a pneumatic DA sander and a very specially designed system of abrasives and backing pads. It works great. :xyxthumbs

In theory I guess you could use a PC but it would scare the heck out of me. The Mirka Bulldog sander:
http://www.mirka-usa.com/mirkaweb_v2%20resources/%20photos/blacksander.jpg
is very small and light and very easy to keep flat on the surface. A PC is rather unwieldy in comparison. That’s not a problem with foam buffing pads but with sanding sheets it would take considerable skill to avoid damaging the finish.

From the description it sounds like he’s using plain old ordinary sanding sheets of a completely wrong grit. :eek:


PC.

[Rusty Bumper]

Originally posted by the other pc
A PC is rather unwieldy in comparison. That’s not a problem with foam buffing pads but with sanding sheets it would take considerable skill to avoid damaging the finish.


Thanks for bringing that up PC.

I was wondering why the PC- DA polisher wasn't mentioned for that purpose.

Looks like a person would need a real flexible air hose for this type of machine though........I mean, a heavy air hose might cause control problems.

[Superior Shine]

The mirka is a finish sander. It has a tighter dual action motion than the porter cable.

[Rusty Bumper]

Sort of like an electric B&D palm sander I suppose.

[the other pc]

A flexible hose helps a lot but it’s not as bad as it might look. Since it’s a one handed operation I find it pretty natural to hold the hose with the other hand. It’s sort of automatic for me to keep it from dragging on the paint but it also helps keep the sander balanced. From using corded electric buffers you get a natural tendency to loop the hose over your shoulder too.


PC.

[Rusty Bumper]

I used to operate a 7 1/2" grinder on my previous job for a number of years. The nature of my work caused me to have to use it one handed a lot of times, and a heavy air hose was just the thing to help stabilize the grinder.

But the big hose did get to be a problem with smaller attachments however.

Just thinking out loud. :D

[showtime]

I might look into buying one of those Mirka systems now. I'm getting hooked up with a painter who hates wetsanding/buffing. I high balled him on the price because I'm busy with Xpel. He took it. So it looks like I've got a lot of wetsanding in my future.

[Kevin Brown]

The Mirka Bulldog doesn't even begin to reach the orbital speed of a standard square style DA sander. Those things are wayyyy too fast!

Comparing the G100 to the Bulldog... As Joe said, it does have a much tighter movement than a G100. The BIGGEST advantage to the Bulldog is that the speed is variable all the way down to ZERO O.P.M. (oscillations per minute). The hose is not a problem... If it seems awkward, simply add a small hose swivel attachment.

In my opinion, this system is easier and safer (and quicker) to use versus hand sanding. We use them at the NXT Tech Institute... In fact, Joe and Paul are NXTti grads!

read about it here:
Inaugural NXT Tech Institute (http://meguiarsonline.com/forums/showthread.php?s=&threadid=1229&perpage=10&pagenumber=1)

NXT Tech Institute write-up! (http://www.meguiarsonline.com/forums/showthread.php?s=&threadid=2802)

NXTti- The Nethercutt Collection (http://www.meguiarsonline.com/forums/showthread.php?threadid=5224&highlight=NXTti)

[Miracle]

The Bulldog is the best one for sanding, whether removing orange peel from clear or removing bird stains and scratches. They also do various sizes, I think there is 3,5,6 inch versions.

As for the Mirka sanding pads, 2000 and 4000 grit sanding pads are the nuts!!! Smooths out paint like never before... and the new ceramic clear coat compounds take out the 4000 like a dream come true...

[Jimmy Buffit]

Here's another :xyxthumbs for the Mirka Bulldog.

In addition to the other comments, I'm not sure that the mix of WETsanding and the electricity of the Porter Cable is a good thing... :eek:

Jim

[Superior Shine]

In addition to the other comments, I'm not sure that the mix of WETsanding and the electricity of the Porter Cable is a good thing...

Don't be a wuss Jim!! Where is your sence of adventure?

[Rusty Bumper]

Originally posted by Jimmy Buffit
Here's another :xyxthumbs for the Mirka Bulldog.

In addition to the other comments, I'm not sure that the mix of WETsanding and the electricity of the Porter Cable is a good thing... :eek:

Jim
Mighty good point!

Never thought about it at first.

No wonder they're pneumatic. :D

Edit: I guess we all need to see if we have our DA polishers plugged into a GFCI receptacle, since they are mainly used outdoors.

[Miracle]

No wet sanding and electric is not a good idea..