Rubbing out, what happened? Help!

[Matt Day]

After letting the 3rd coat of Rockhard Varnish dry for 2 weeks, I just attempted my first rubbing. I first leveled with 600 w/d paper with water, using very light, long strokes. Then I used pumice powder with water and 600 w/d paper. The two pictures show the difference between it when it's dry, and after spritzing it with water and going over it with a dry rag. It looks good to me when wet, but obviously it will dry and look spotty like the "dry" picture shows.

What did I do wrong? What should I do? Apply another coat of varnish and give up on the rubbing?

TIA

[Howard Acheson]

The problem is that you have not use fine enough abrasives if you want to produce a high gloss and if you are trying to create a high gloss, you are going about it incorrectly. First, sand with 400 W&D paper mounted on the sanding block. The objective is to flatten the surface. Next, use 600 W&D, then 1200 W&D. You can use water, mineral oil or mineral spirits as your lubricant. Follow this with pumice applied with a felt rubber with mineral oil. Finally use rottenstone applied with a clean felt rubber with mineral oil to produce a mirror finish. This should produce a high sheen.

Most finishers use synthetic rubbing and polishing compounds these days applied with an electric buffer. Sand up to the 1200 with W&D paper. Then use a white polishing compound applied with an electric buffer. Then use Maguires Swirl Remover machine applied with the buffer.

Finally, you will find that rubbing out the finish works better if you give the finish 3-4 weeks to cure fully.

You might want to get Flexner's Understanding Wood Finishing for a more detailed description of rubbing a finish to a high gloss.

[Matt Day]

Maybe I'll take a trip to the bookstore and check that out.

I suppose the dull/rough looking spots are areas that I did sand, and the shiny spots are places that were not. In other words, the surface wasn't completely leveled; is that correct? I was very tentative to apply much pressure in fear of rubbing through the layers.

Would I be correct to go back to 400 W/D paper and be a little more agressive, and sand to the point where everything is dull/rough looking? Then go to 600, 1200, pumice, then rottenstone?

As I said, I'm just tentative to sand too much and go through the varnish.

Thank you for your input Howard.

[Steve Schoene]

It's likely the dull spots are high spots and the shiny spots still not quite leveled spots. It's a challenge to get all the leveling accomplished in the final coat. Sometimes you do cut through the final coat, into the lower coats, revealing faint but distinct lines (witness lines) that look like the lines on a topographical map. Another varnish coat will make these dissapear. It's the next to last coat that should have the serious leveling, with the expectation that an evenly applied final coat will level without cutting through, and can then be rubbed to what ever gloss you want. Leveling this last coat can probably be done with 600 grit, reducing the risk of cut through. Then go to 1000 or 1200 grit, and then directly to pumice for a satin finish or to polishing compound or rotten stone for glossier finishes.

I know that the typical instructions all say not to skip grits, but that's only good advise if you never go past the point where is time to shift grits. It's a speed--efficiency thing, not a quality thing. More risk of cut through the more grit levels you go through.

[Matt Day]

Thanks Steve.

I'll probably do some leveling with 600 and see how much material I end up taking off. If it seems like it takes too much, I'll apply one more coat of varnish. If not, I'll go up to 1200 grit then to pumice.

So the dull spots will polish out to a higher gloss when I go up in grits (and/or to pumice and rottenstone) right?

[Russ Filtz]

Yes, just like the Scary Sharp process for chisels!

[Matt Day]

Please convince me not to throw this tabletop out the window!!!!:mad:

I don't know what is going on here. After figuring that I didn't level the surface enough, I went all the way back to sanding with 220. I then applied another coat and let it dry for a couple days, then sanded with 400 lubed with water. Then I applied a last coat thinned with mineral spirits, and let it dry for about 4 days. Tonight I went at it with 600 lubed with water, then to 0000 steel wool (dry), then to 0000 with pumice, then 0000 with rottenstone. I applied a bit more than moderate pressure when rubbing.

The results? Terrible. There's no satin or gloss anywhere, just dull. I'd rather have left the last coat that I applied with the mineral spirits and just dealt with the brush marks.

Can someone tell me how I can salvage this project?

I'm using the guidelies on FWW #132, Wiped-On Varnish, and FWW #168, Varnishing Secrets.

[Steve Schoene]

Dry 0000 steel wool is going to give a fairly matt "satin". For a more satin satin it should be lubricated. But using the steel wool as the pad for other abrasives isn't going lessen the effect of the steel wool. The other abrasives are applied and rubbed with felt pads or the like, not with steel wool. And, applying more that moderate force won't help. The more force the deeper the scratches, the deeper the scratches the less glossy the surface.

After only a few days, the varnish isn't very well cured. It will be harder, and therefor easier to rub to a gloss if you wait longer before rubbing out.

If your goal is gloss, then you don't need steel wool at all. Put on one more coat, as smoothly as possible. Ideally, it should cure for a month before rubbing out. You should still be able to get decent results after a week or so.

When it has cured as long as you can stand it. Arrange for strong lighting at a low angle across the surface so you can see.

1. Sand very lightly with 600 grit w/d paper lubricated with water that has a drop of hand dishwashing soap in it. (JUST a drop for 2 cups of water--it is only to reduce surface tension, not make "soapy water".) As you sand look for any larger defects that the 600 grit doesn't almost flatten out in a ffew light passes. Remove these defects by dropping to 400 grit and then go back to 600 grit to get an even scratch pattern. You will need to wipe off the surface frequently to see what is happening under the lubricant.

2. Jump to 1000 grit, and just wet sand until the 600 grit scratches have been replaced with even 1000 grit scratches.

3. a. If you want glossy, go directly to rottenstone, lubricated with paraffin oil using a felt pad. You don't need pumice first. Wipe dry fairly often to observe your progress.

or

b. (1) If you want satin use pumice, lubricated the same way.

or

(2) Or you can use 0000 steel wool lubricated with wax or the paraffin oil. I don't find this gives quite as even a surface as the pumice, but the differences can be small.

So it is just a matter of 1, 2, 3.

[Matt Day]

Thanks for the reply Steve. I'll give it one more shot.

I used 0000 per Thomas Wisshack's article in FWW, where he says to rub with dry 0000 with moderate pressure before going to 0000 with lube.

At any rate, I'll try your suggestion and apply another coat (probably about the 6th or 7th at this point). One of the troubles I have is seeing the progress as I go during wet sanding. It looks great when it's wet, but dries to a dull haze at each stage. I suppose I need to do a few passes when it's wet, wipe it off with a rag, then let it dry completely, then check the progress before rubbing more.

I've NEVER seen any shine unless it's right after a coat of varnish has been applied or while it's still wet. It seems that as soon as I touch it with sandpaper it's goes dull and I can't get it to shine.

Edit: Parrafin oil is mineral oil right? I thought I remembered reading that parrafin oil is another name for kerosene, but I think I'm mistaken.

[Dennis Peacock]

Matt,

Paraffin oil is kerosene. You can get it at most stores like Wal-Mart in the oil lamp section of the store. Paraffin oil burns cleaner that standard kerosene.

I've used mineral oil to run out, just be aware that it's "thicker" than paraffin oil and it's not as easy to clean off the surface as paraffin oil. I've also used standard mineral spirits with very good results. Make sure you get a felt block for this rub out if you are going with a gloss finish. The felt block has no "grain" and it won't impart any particular "pattern" to the finish.

BTW, rubbing out with 4 aught steel wool won't give you what you are looking for in your finish. I use 4 aught for a flat or semi-gloss finish.

Post pics of your progress when you can.

[Matt Day]

I'll post some pics when I get home, but I surely wouldn't call it "progress.":rolleyes:

I'll pick up some true parrafin oil next time I'm out. And I'll use it and some felt pads next time. I don't know why that FWW article would have said to use 0000 if it doesn't work well. Oh well, we'll see how the felt pads work.

I'll apply a coat of varnish tonight and let the curing process begin. I have off on the 4th, so hopefully it will be cured sufficiently by then. Are there any tricks to speeding up the curing process? I would guess it's better to be in an air conditioned space rather than a hot humid area?

[Dennis Peacock]

Matt, you can help speed the drying process by thinning it with Naptha. The naptha flashes off faster than just varnish or varnish thinned with mineral spirits. I use naptha when I need the finish to dry faster. I just don't use much varnish type finishes any more due to the long dry/cure time. Most of my finishes any more are Lacquer or shellac, as I like how quickly I can build a finish and allow it to start the cure process quicker.

Best of luck to ya bud. I hope it all works out for ya.

[Steve Schoene]

Naptha does speed the process of initial drying, but its only effect on the overall curing is that a thinner coat cures faster because of more oxygen contact. But the over all cure isn't affected since the thinner, naptha or mineral spirits has entirely evaporated in a couple of days.

To really speed the cure increase the heat. Cure at 85° will be much faster than at 70°. Lower humidity also speeds cure, but I don't think it is as dramatic past the initial thinner evaporation stage.

[Al Willits]

Newbie to wood finishing, but I've done a ton of auto/bike painting and the biggest thing is patience, sounds like your trying to hurry the process, can't do that, the wood finishes I've played with have been even touchier than I thought they'd be.

Sloooooooow down and take your time, when in doubt, leave it still.

I finding it helps to have two projects going at the same time, least the second one will keep you occupied and not thinking of attacking the other project...to soon :)

Good luck
Al

[Matt Day]

Here are some (poor quality) pics after I rubbed it out. As previously discussed, I think my major fault was using steel wool with too much pressure. I'll post back with an update when the coat I applied last night cures and I get to rubbing, again.

[Denise Palko]

Matt,

I am very interested in your project. I am making a similar table top -- center field is wormy maple with walnut on each side and walnut breadboard ends. The legs and aprons are all in walnut.

I expect to start the finishing stage next week and I've been stressing over the options for a few days now. I was planning a simplier finish of Waterlox Original or Watco Danish Oil (Natural color). I was just at a local, woodworking store today and the owner suggested Watco and then a Johnson's wax buffed out. Obviously, this isn't a very hard finish (hard as in tough or durable), but could achieve the look I was after.

Good luck with your finishing tomorrow.
Denise