LumberJocks

Rubbing out a finish to high gloss

  • Advertise with us

« back to Finishing forum

Forum topic by Purrmaster posted 02-28-2013 03:20 AM 6025 views 1 time favorited 33 replies Add to Favorites Watch
View Purrmaster's profile

Purrmaster

832 posts in 840 days


02-28-2013 03:20 AM

I’ve been trying for a year now achieve a mirror like, high gloss shine on a finish. The finishes I’m primarily talking about are lacquer and shellac. I’ve read these finishes rub out best. The highest sheen I can get to is a semi-gloss. Usually more like matte. It’s driving me nuts because I see all these pictures of super gloss, mirror like finishes and I can’t seem to get to it.

I’ve tried the following (it’s a bit of a list:

Pumice and rottenstone. During french polishing with shellac. Also with a felt block. I’ve tried mineral oil and paraffin oil with rottenstone/pumice.

Sanding through the grits from 220 up to 2,500 with conventional wet/dry sandpaper. I’ve done it dry, with water as the lubricant, mineral oil as lubricant, and mineral spirits as lubricant. I’ve even got a piece of 3,000 grit “paper” (3M Trizact).

I’ve tried Micro Mesh up to the highest possible grit (12,000) using the lubricants listed above. I’ve tried 3M microfinishing film as well as 3M polishing papers (both up to 1 micron). I didn’t skip any grits.

I’ve tried Meguiar’s Swirl Remover 2.0, Meguiar’s Show Car Glaze, Turtle Wax polishing compound, Turtle Wax rubbing compound, Meguiar’s ScatchX and several brands of wax.

And probably a few other things I can’t remember at the moment.

What the hell am I doing wrong? I’d say I have to rub with even finer abrasives but I don’t think there is anything finer out there.

As I said the finishes I’m primarily trying to rub out are nitrocellulose lacquer (brushing lacquer, I don’t have spray equipment) and shellac. Both dewaxed and waxed shellac. But I’d like to be able to accomplish the same task using finishes like polyurethane, water base, and other varnishes. Basically any film building finish.

Thanks.


33 replies so far

View needshave's profile

needshave

150 posts in 707 days


#1 posted 02-28-2013 03:38 AM

I would never use the wax you are using to get a good quality luster/finish. Once sanded to my highest grit I then apply several coats of Johnson’s paste wax. Put it on light, let it start to haze then buff it off. It’s a good quality product and intended for this application. I would not use automotive wax on the finish. You can buy Johnson’s wax at Lowe’s for $4.95.

View Clint Searl's profile

Clint Searl

1479 posts in 1108 days


#2 posted 02-28-2013 03:57 AM

For lacquer or poly:
Wet sand to 600 with soapy water to level the surface
Rub out with automotive rubbing compound
Followed by automotive polishing compound

-- Clint Searl....Ya can no more do what ya don't know how than ya can git back from where ya ain't been

View Purrmaster's profile

Purrmaster

832 posts in 840 days


#3 posted 02-28-2013 04:32 AM

I use wax as a final topcoating in order to protect the finish. I use Minwax paste wax and Johnson’s paste wax, not automotive wax. I should have been clearer.

Precisely what automotive rubbing and polishing compounds should I use? As I said, I’ve used several already and they didn’t work.

View CharlieM1958's profile

CharlieM1958

15794 posts in 2966 days


#4 posted 02-28-2013 05:10 AM

The methods you have listed should give the result you are looking for. Are you starting with a perfectly smooth finish? If you are working with an open grained wood like walnut, you need to use a grain filler of some kind.

You really need a significant buildup of finish to be able to rub it out to a high gloss. Have you tried using additional coats before sanding and rubbing?

-- Charlie M. "Woodworking - patience = firewood"

View Purrmaster's profile

Purrmaster

832 posts in 840 days


#5 posted 02-28-2013 05:21 AM

I get a smooth finish by starting in the lower grits. With sandpaper I usually go like this: 220-320-400-600-800-1,000-1,5000-2,000-2,500.

Typically by the time I hit 400 grit the finish is smoothed and leveled out. When I’m done I have a finish that feels perfectly smooth to the touch but doesn’t look it.

The woods I’ve tried this on so far have been woods like cedar and madrone. I haven’t tried a high gloss finish on oak and the like yet. If I do I intend to use Aqua Coat grain filler. I have some on hand.

If the procedure is correct than I must be screwing it up somehow.

I try to put a fairly thick film on there. But I’ve read that if you put it on too thick the film may crack. So I try to strike a balance.

View shipwright's profile

shipwright

5304 posts in 1545 days


#6 posted 02-28-2013 05:22 AM

Once you have your pore filling done with a tiny amount of pumice and alcohol with a few drops of shellac, finishing in French polish should involve no abrasives…. only shellac, alcohol and a very small amount of mineral oil.
The techniques vary with the practitioners but the results should be mirror-like with just the polish, no waxing necessary.
I don’t use the other materials so I won’t comment on them.

-- Paul M ..............If God wanted us to have fiberglass boats he would have given us fiberglass trees. http://prmdesigns.com/

View Mark Kornell's profile

Mark Kornell

644 posts in 1278 days


#7 posted 02-28-2013 06:09 AM

First, shellac won’t polish using abrasives all that well. It doesn’t get hard enough, and with not much friction, it will heat and melt a bit. As shipwright says – us shellac, alcohol and mineral, using a pad.

For poly/lacquer and other hard film finishes, you can use abrasives. You first need to let them cure fully. In the case of poly, that could be up to a month. Lacquer can be done sooner.

Once it is cured, Clint S has it right. Although personally, I wet sand to 1500 or 2000. That’s probably overkill, but it works for me.

And when he says “automotive rubbing compound/automotive polishing compound”, that’s not the stuff you find on the shelf in the automotive section at Walmart. Its the stuff autobody guys use to polish out car finishes. You’ll probably have to go to an autobody supply shop (maybe something like a Pep Boys) to find it. 3M makes a line which I’ve used to good effect. Instrument makers do this all the time, so you might want to check on their forums for specific brand recommendations and where to obtain.

Make sure you don’t contaminate your buffing pads as you work up through compounds. Use a separate buffing pad for each compound, make sure that you isolate where you set each down, and clean your piece after each compound.

-- Mark Kornell, Kornell Wood Design

View Airframer's profile

Airframer

2739 posts in 700 days


#8 posted 02-28-2013 06:19 AM

Yep, cure time with the Nitro and the Poly is the key. The methods you described is exactly how I refinish guitars but I usually let the clear cure for over a month (I have had some take longer than that) if it still smells like paint it ain’t cured yet just let it sit.

Lacquer and Poly cure from the outside in so if you try to shine an uncured Lacquer or Poly all you are doing is exposing the uncured portion under the skin that has developed and it is just too soft to shine up to a mirror finish. Follow the rule of 3 with those finishes. 3 light coats, no more than 3 a day, wait 3 days before applying more and then 3 weeks per set of 3 for cure is how I go about it. Patience is the key.

-- Eric - "I'm getting proficient with these hand jobbers. - BigRedKnothead"

View Purrmaster's profile

Purrmaster

832 posts in 840 days


#9 posted 02-28-2013 07:21 AM

Thank you for the replies. Please, keep them coming.

The woods I’ve used french polishing on so far aren’t porous. I have used the alcohol/pumice/rottenstone method anyways but the pores didn’t need filling. I did it mostly for the sake of smoothing out the finish.

I’ve also tried french polishing without using any sandpaper at all. The sheen is still too low. It’s not mirror like. Most of the examples of mirror like finishes I’ve seen are french polished shellac. That’s one of the reasons it’s so aggravating that I can’t seem to achieve it. The gloss is supposed to be inherent to french polishing.

Don’t worry about the wax. I shouldn’t have mentioned it in the first place. My apologies.

Which 3M line of compounds are you referring to? I’ve looked at their web site and 3M makes about 5 trillion different automotive thingies. Meguiar’s makes a large number of products too.

The one thing I can think of that I’m missing is a dual action polisher. But I figured using the automotive compounds by hand would work, it would just take longer. On the other hand I can’t seem to get quite as uniform a surface with hand sanding wood as I can with my random orbital sander.

I think the step where I’m getting messed up is after the wet sanding is done and one has to turn to rubbing/polishing liquids. I saw a picture of a paint finish that was sanded up to 5,000 grit using 3M Trizact sanding disks. It was still a semi-gloss finish and the guys on the forum were talking about having to take out the sanding scratches. Even with 5,000 grit.

I may be using the wrong sequence of thingies, the wrong thingies, or using them wrong.

View Jorge G.'s profile

Jorge G.

1526 posts in 1222 days


#10 posted 02-28-2013 07:58 AM

Ok, don’t mean to sound like a jerk but you are trying two different varnishes, concentrate on one until you get it right then move on to the other one.

For lacquer I use the car polish trick, I wait at least 12 hours after the last coat to sand and re coat with lacquer, once I have put the coats I want I do a wet sand like you, apply the car polish and buff with a power buffer. It should work, maybe you are not giving the lacquer enough time to cure and harden.

For the french polishing, is your shellac fresh? is it waxed or dewaxed? I cannot tell you why is it not working for you, you are doing all the correct steps.

-- To surrender a dream leaves life as it is — and not as it could be.

View Purrmaster's profile

Purrmaster

832 posts in 840 days


#11 posted 02-28-2013 08:42 AM

You’re right. Shellac and lacquer are two very different animals. I mentioned those because I read in Flexner’s book that those finishes rub out best. Varnishes, especially, polyurethane, don’t rub out as well simply because they are so scratch resistant. Though I’ve got some Waterlox, which is a phenolic varnish so maybe it will rub out nicely.

Here’s been my procedure for french polishing. I’ll usually brush on some thin shellac to build it up. Then go for a few bodying sessions with alcohol, shellac and mineral oil. Gradually putting in more alcohol and less shellac. Then I’ll use a different rubber/fad with just alcohol and 4F pumice. Usually I’ll wet sand from 400-2,500. I use mineral spirits as the lubricant. Then a couple more bodying sessions. Then rottenstone. A few more sessions of rubbing with the charged rubber/fad and then let it sit overnight. Then get the mineral oil off with naptha.

I’m still not left with the gloss that I want. I’d take a digital picture but I figure the flash render it useless. I’ll try a few trial shots.

With lacquer I start at 220 and then sand up to 3,000. Or with MicroMesh start at 3,600 and up to 12,000.

View Francisco Luna's profile

Francisco Luna

936 posts in 2141 days


#12 posted 02-28-2013 09:52 AM

I found this site to be VERY VERY helpful before, hope that helps.
http://www.milburnguitars.com/fpbannerframes.html

-- Nature is my manifestation of God. I go to nature every day for inspiration in the day's work. I follow in building the principles which nature has used in its domain" Frank Lloyd Wright

View Purrmaster's profile

Purrmaster

832 posts in 840 days


#13 posted 02-28-2013 10:53 AM

Thank you for the link. I’ve used that site as one of my tutors on french polishing. It’s a good site.

View RogerInColorado's profile

RogerInColorado

306 posts in 702 days


#14 posted 03-01-2013 01:22 AM

This is a pretty good tutorial as well. This is Part 1. http://www.youtube.com/watch?v=zN-9vCSJWDQ

after you watch it, make sure to watch part 2 http://www.youtube.com/watch?NR=1&v=aV9y44JXXGU&feature=endscreen

View HorizontalMike's profile

HorizontalMike

6968 posts in 1661 days


#15 posted 03-01-2013 01:35 AM

+10 on the Johnson’s Paste Wax (JPW) over shellac suggestions given above. I got such advice on my first and only shellac finish and it turned out very well.

I actually utilized a cotton sham on a 9in powered buffer to apply the JPW, testing as I went so as to not polish all the way through the shellac.

-- HorizontalMike -- "Woodpeckers understand..."

showing 1 through 15 of 33 replies

Have your say...

You must be signed in to reply.

DISCLAIMER: Any posts on LJ are posted by individuals acting in their own right and do not necessarily reflect the views of LJ. LJ will not be held liable for the actions of any user.

Latest Projects | Latest Blog Entries | Latest Forum Topics

HomeRefurbers.com

Latest Projects | Latest Blog Entries | Latest Forum Topics

GardenTenders.com :: gardening showcase