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View Full Version : Roto-orbital sander as polisher



Cesar Vega
10-04-2010, 4:14 AM
Hi,

Either this is a very obvious question or a stupid one.

But I read at some forum that one could use a roto-orbital sander as a polisher.
I don't have have a roto-orbital sander, neither a polisher, but I plan to buy both at some point. My current sanders are square and as polisher I use my left arm :).

(I'm going to buy this one: http://www.amazon.com/DEWALT-D26451K-5-Inch-Random-Sander/dp/B0007XXHGO/ref=sr_1_1?ie=UTF8&s=hi&qid=1286176401&sr=1-1)

I know a polisher does not have a very high speed. I understand a roto-orbital sander it's fast. But I'm not sure how much.
Besides the sander has that mechanism to vaccum the dust, which would become blocked with a wool pad.

What do you think? Is it possible?

Joe Spear
10-04-2010, 8:50 AM
Festool has a video showing how their sanders can take a piece of rough wood to a fine shine by going through grit steps all the way to to a buffing head. I don't know why you couldn't do that with another brand of sander.

Cesar Vega
10-04-2010, 12:08 PM
Hi,

Thanks for your response.

I made a little research and found out that Sander which are feature as Polisher too, have a Variable Speed control.

Like this one:
http://www.boschtools.com/Products/Tools/Pages/BoschProductDetail.aspx?pid=3725DEVS

Also, I read that high speed rotation tools might simply burn the finish and than lower rotation rates are needed for polishing.

So, well, I think that's the catch. If you are able to slow down the rotation then you can use it as polisher, too, and that's it.

Will Overton
10-04-2010, 12:25 PM
My first ros (20 years ago) was a Bosch. It came with a polishing bonnet ...it was variable speed.

Prashun Patel
10-04-2010, 12:27 PM
Wood Magazine had an article a month or two ago about doing this. You can do it with a ROS. The key is using the right polishing compound and a buffing pad.

Neil Brooks
10-04-2010, 1:21 PM
Wood Magazine had an article a month or two ago about doing this. You can do it with a ROS. The key is using the right polishing compound and a buffing pad.

Ayup.

I think I read the same article.

I'm fortunate enough, though, to have scored a refurb'd P-C dual-action polisher (that I use to polish the cars, 2x/yr).

I haven't used it on furniture projects ... yet ... but probably will.

Curt Harms
10-04-2010, 6:32 PM
A P-C 7455 5" right angle ROS doesn't work to polish metal, it doesn't rotate fast enough. It will buff wax okay.

John McClanahan
10-04-2010, 8:02 PM
I have a PC right angle ROS. From what I understand, the only difference between the sander and polisher is the pad and counterweight. The motor is the same.

John

Alan Lightstone
10-04-2010, 10:31 PM
PC ROS stop rotating when enough pressure is applied to them. You really don't have to push down hard at all to cause that to occur.

What you really want (and what's become very popular in car detailing circles) is a ROS with forced rotation. The Flex XC 3401 is awesome for car polishing (safer than a rotary sander, but can obtain a similar finish.) No matter how hard you push on it, it's geared rotation will continue rotating. Well balanced too.

I've never tried mine on wood, though, as the thought of a wood chip destroying the paint on one of my cars prevents me.

I'm often surprised when polishing compound is suggested in the woodworking magazines for polishing wood. That's a very coarse compound, only used on cars whose paint is essentially trashed.

Any of the microparticle polishes which are state of the art for cars now, have much smaller particles, and, I would assume, would produce a much smoother, lustrous finish. Again, I've never tried this on wood. I keep meaning too, but I don't want to risk ruining my cars.

Jim Becker
10-04-2010, 10:54 PM
PC ROS stop rotating when enough pressure is applied to them. You really don't have to push down hard at all to cause that to occur.

Very true. I never found using a ROS for this was the most effective method. However, my Festool Rotex in rotary mode does work well for this. Other tools that also use the "forced" rotation that Alan described would also be better suite than a ROS.

Neil Brooks
10-04-2010, 11:05 PM
I'm often surprised when polishing compound is suggested in the woodworking magazines for polishing wood. That's a very coarse compound, only used on cars whose paint is essentially trashed.


In the automotive world, I think what you're describing is FAR more true of rubbing compound than it is of polishing compound.

Alan Lightstone
10-04-2010, 11:30 PM
I agree, but they are both far more abrasive than true polishes. I may be getting caught up in the syntax, however.

Dave Lehnert
10-05-2010, 12:19 AM
The Porter Cable unit is very popular with car people. I purchased one on close out at Lowe's for woodworking that came with the polisher kit.

http://www.autogeek.net/hk7424.html

http://ecx.images-amazon.com/images/I/41YmnLlLg1L._SL500_AA300_.jpg

Alan Lightstone
10-05-2010, 1:40 AM
The Porter Cable is far more popular than the Flex with car people. I own both it and a Flex. Part of that is cost (the PC is far cheaper), and it's been around forever.

Once you use the Flex, the Porter Cable sits in the closet (except for putting on sealant, because it's lighter than the Flex, and power is irrelevant for that.) It's more effective (about as effective as a rotary, but with much less risk of burning the paint -- or in this case wood.)

If I had to use one of these for woodworking, it would be a no-brainer for me to use the Flex. It's just better technology. They work in different ways. Forced, geared rotation is far more effective.

That being said, I've not used it for that (though I've detailed a zillion cars with it), so I'm not an expert on this use.

Jeffrey Makiel
10-05-2010, 10:26 PM
I just polished a repaint on my truck's hard tonneau lid this weekend using the Porter Cable polisher that Dave shows in his post above.

The machine was able to polish the finish after wet sanding with 2000 grit. Automotive urethane is very hard. First came the compound, then the polish, and completed with a hand glaze. The PC is slower than the usual right angle polishing wheel, but it is also more forgiving as burn marks are not an issue.

I bought my PC as a polisher. I'm not sure if the eccentric is the same as the sander version. I used it with Lake Country sponge wheels. They come in various coarseness. I've also used it for general polishing of tired automotive finishes with very good result.

I have an old Bosch random orbital sander that came with polishing bonnets. It works OK for very light polishing, but it was much less capable than the PC and not up to the job to restoring old finishes.

Hope this helps,
Jeff :)

Curt Harms
10-06-2010, 8:53 AM
I don't have the polisher but I suspect it has the forced rotation function. As previously stated when I put much pressure on sander, the surface rotation nearly stops and it becomes more of a jittery motion. Works well for sanding, not very effective for buffing or polishing. I've watched aircraft detailing crews polish brightwork. They were using what appeared to be DeWalt angle grinders with 8"-10" fabric disks.

John McClanahan
10-06-2010, 9:01 AM
DeWalt makes a large right angle buffer. I don't think it has random orbit, though.

John

Alan Lightstone
10-06-2010, 4:57 PM
I don't have the polisher but I suspect it has the forced rotation function. As previously stated when I put much pressure on sander, the surface rotation nearly stops and it becomes more of a jittery motion. Works well for sanding, not very effective for buffing or polishing. I've watched aircraft detailing crews polish brightwork. They were using what appeared to be DeWalt angle grinders with 8"-10" fabric disks.
The Porter Cable doesn't have forced rotation. What you are describing sounds like a typical random orbital sander.

With forced / geared rotation, no matter how hard you push on the sander, the disk keeps turning, not just oscillating.

Mike Fitzrad
10-12-2010, 6:22 PM
Funny.. I just posted a similar request. There is critical question.. what are looking to polish? If its Lacquer, then you have to use a variable low speed - below 2200 - according to the Fine Woodworking site that has a good article on French Polishing - which is what I am after. I'm dong cigar boxes.

My challenge is finding a palm based variable polisher that is 6" or smaller.

Question for the group: What tool do you use to polish smaller projects? BTW - I use the 3m imperial polish. Very expensive by fantastic on lacquer.

Cesar Vega
10-12-2010, 7:13 PM
I think I'm going to buy a good roto-orbital sander, first.

Then, get a cheap 5" polisher at autozone, for $30, and see how long does it last.