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View Full Version : What do people prefer to rub out a varnish finish



Alan Lightstone
02-25-2012, 3:16 PM
I'm looking at two different approaches:

One would involve Behlen pumice and rottenstone, with paraffin oil and Abralon. Done by hand.

A second approach would involve using Menzerna 2L Pre-Polish compound followed by 16 Fine Polishing compound. This would be done with the Flex ROS that I have (or perhaps my Festool 150/3) using Surbuf Polishing Pads. I have a great deal of experience on exotic cars with polishing, though none with polishing wood.

The last possibility I've seen is what Charles Neil demonstrates on Woodcraft's web site with Micro-Mesh and a ROS. Probably go up to 6000 or 8000 grit.

The final finish I am looking for would be semi-gloss to gloss. Perhaps not fully to grand piano like, but maybe slightly less glossy.

Will I have more control over the level of gloss using the Micro-Mesh? Is the Micro-Mesh more or less likely to sand through the finish and cause witness lines? Is the pumice and rottenstone approach more all or nothing (semi-gloss with pumice / gloss with rottenstone)?

Scott Holmes
02-25-2012, 7:37 PM
Micro mesh. Pumice and Rottenstone are the old school and very messy way to rub out a finish. They were used way back when, because micromesh and the super fine 2000, 3000, 4000, 6000, 8000 and 12000 grits were not available.

You are not rubbing out wood you are rubbing out finish just like on a car you're not sanding steel only finish.
ROS can remove too much finish quickly; use mineral oil as a lub till you get the hang of it, then mineral spirits is a bit faster.

Brian Kent
02-25-2012, 8:51 PM
I took scott's advice on this one and used a ROS with micromesh pads on waterlox and it worked spectacularly.

Sam Murdoch
02-25-2012, 10:28 PM
I took scott's advice on this one and used a ROS with micromesh pads on waterlox and it worked spectacularly.

There's your answer Alan :)

Alan Lightstone
02-26-2012, 12:54 AM
Yup. Thanks Scott, et al.

Never heard the mineral oil advice. Interesting pearl.

The technique really isn't different than polishing a car and not burning through the clearcoat, is it?

Nick Sorenson
02-26-2012, 9:26 AM
Micro mesh. Pumice and Rottenstone are the old school and very messy way to rub out a finish. They were used way back when, because micromesh and the super fine 2000, 3000, 4000, 6000, 8000 and 12000 grits were not available.

You are not rubbing out wood you are rubbing out finish just like on a car you're not sanding steel only finish.
ROS can remove too much finish quickly; use mineral oil as a lub till you get the hang of it, then mineral spirits is a bit faster.

One thing to point out to anyone reading, take Micromesh's grit numbering system with a grain of salt (or maybe a grain of silicon carbide). If you compare them with P scale numbers they're much different I found. The 12000 seems like maybe P3000 and the lower numbers are also quite a bit courser.

When I first heard their 12000, I thought WOW! that's like a polishing compound. It's still a sanding grit, you'll need to polish. But it is good stuff. Just not what you think when you hear 12000.

Also, other good materials are other foam backed discs such as Mirka Abralon and the many equivalents (Sia Air, Fandeli Supreme Foam, Klinspor's new foam, etc.).

I personally find good old wet dry to work fine in the finer grits. Eagle Abrasives, 3M Imperial, Fandeli and many others make a good wet dry silicon carbide paper and it's much cheaper than the foam or Micromesh if you still have to buff/polish anyways.

The glossier you go the finer you better sand or you'll see the scratches.

Orbital sanders leave pigtail scratches. I recommend using the foam backed pads if you have to use an orbital and go all the way to 4000 grit if you're after gloss. I always go to a very high gloss and I find I do not like orbitals in the final grits (or anything after the last clear coats for that matter).

Alan Lightstone
04-25-2012, 7:47 PM
Finally, after a month of curing, I've started rubbing out the waterlox on the bottom of the drafting table top. I've gone through 8000 grit of Micro-Mesh (using Scott's advice above - thanks, Scott). The finish looks a little lifeless, though probably of the correct gloss range. Not sure how to explain it, except the untouched finish was more spectacular (though too glossy for my wife's taste).

I tried a coat of Rennaisance wax on top which helped, although it has streaked like crazy. It does feel great, though.

Any thoughts as to adding more life to the finish?

How to get rid of the streaking in the wax? I've tried elbow grease with a micro-fiber cloth, as well as a ROS buffing pad. Neither one has eliminated the wax streaking. Is it just not dry yet?

I want to sort out all these details before I move to the top of the drafting table (next step).

Brian Kent
04-25-2012, 8:00 PM
I would take the wax off and keep micro-meshing to 12000.

sheldon pettit
04-25-2012, 8:19 PM
trying to control the degree of gloss and having it turn out uniform is not easy, better to just spray apply your last coat with a 80-90 degree sheen and be done with it. Though any methods mentioned will work - perfect uniformity will be difficult. Many times you'll find the pumice to contain some larger particles that leave a bit larger scratch than the others, then the RS will have to be used more to remove such and in doing so, bring the gloss up more in those areas if they occur. You may get lucky though, who knows. Since you don't state what the surface is on or the type of varnish and how long applied and if your able to apply a final dust free coating, it's up in the air as to suggestions.

Alan Lightstone
04-25-2012, 9:35 PM
OK. Wood is sapele. Finish is Waterlox Original Sealer/Finish. Wiped on. Multiple coats. Cured for 1 month.

What's the best way to take the wax off, btw?

Here's a picture of the top before rubbing out (glossier than we desire, on purpose):

230575

sheldon pettit
04-26-2012, 12:02 AM
OK. Wood is sapele. Finish is Waterlox Original Sealer/Finish. Wiped on. Multiple coats. Cured for 1 month.

What's the best way to take the wax off, btw?

Here's a picture of the top before rubbing out (glossier than we desire, on purpose):

230575

Well... that gives a better clue as to where your really at right now for sure. At first glance it looks very nice, but on downloading and magnifying you've got a long way to go yet. For instance, where the light shows up the pock marks or fish-eye like dips, there is much sanding to be done to really get it as smooth as glass before any compound work of any type takes place. Unfortunately, so much may be removed that further build coats may be necessary from what i see as to some areas. That may lead to further problems if the same thing happens again. If more coats are needed then more drying time will also be needed. Personally i would have chosen something other than waterlox for this job, oh well.... As to wax removal, by the time you get all your problems sanded out with heavier grits [600] your wax will be gone, to insure you can wipe it with a mix of 50/50 turps and mineral spirits before-applying any other materials, keep updating as to your progress and finding ok?