I just finished applying the 3rd coat of finish on a maple table/desk for my daughter last night. I used General Finishes Arm-R-Seal Tung Oil and Polyurethane (I can't tell whether it actually has tung oil in it or not), applied with a foam brush. The finish is mostly smooth, but has very tiny residual bumps in it (you can feel them with your finger). I followed directions, sanding with 320 after the first coat, and #000 steel wool after the second. It says not to sand/wool the final coat.
My question is, can I sand/buff very lightly with something to get those little bumps out? I'm thinking maybe a 600 or 800 grit sandpaper. Should I try a buffing wheel?
BTW, I had what I thought was a great surface on the top, though I didn't do a great job matching wood grain. I used handplanes and scrapers to get it glasslike. The maple I used turned out to be moderately curly, and the surface looked really stunning. I used an Arm-R-Seal stain on it, and basically destroyed the surface. It was blotchy, and made the figure look like accidents, rather than the subtle paterns that would change based on the light and viewing angle. I ended up scraping off the stain, and re-surfacing with the handplanes and scrapers, but I was not able to get the surface back to the same state. I got it smooth, but the figure was more muted than before. This was a long background to the question of "is staining figured wood just an exercise in frustration?" What other methods of sealing/finishing could I have used to preserve the figure and still get a durable finish? I suppose I could have tried to just use the Tung Oil/Poly sealer without stain, but I was trying to enhance the color just a bit to match some other maple furniture.
I've noticed that I tend to get tiny bubbles when using a foam brush to apply a poly finish. For me, this happens when I apply too much pressure on the brush and the bubbles are squeezed out of the foam.
To correct this, I'll either use VERY LIGHT pressure on the brush (doesn't always work), or I'll use a quality bristle brush ... again with light pressure.
If you can't find any 2000 grit paper, a friend of mine (luthier that he is) suggests plain brown craft paper (like a paper bag).
For the problem of not being able to get the glass-like surface you had after re-scraping/planing, Mister Mangler may be able to help. He had a similar problem some time back and may remember what he did, if he was able, to get that surface back. I'm sure he, and his dancing baby, will be by shortly!
FWIW, I'm still VERY new at all this, but I've read that an oil-based finish will penetrate the wood and bring out the figuring in curly maple, etc. Something about allowing the light to penetrate into the wood. Hey, I said I was new at this!! :+ You may try to search for "oil-based poly". I think that's what the discussion was about on the Forum.
Hate to make a long post longer, but I went back and searched "oil based poly". There are some discussions and fairly lengthy threads that address some of your concerns. Give 'em a try.
If you don't have much success with MadMark's method because you can't find the 2000g sandpaper (Lord knows I can't), and the brown paper bag doesn't work as well as you'd like, you can go ahead and sand this just as you would any other coat with 400g or 600g, and then re-aply a final coat thinned 50% with VM&P Naptha.
While this is already a wiping varnish, and the thinning simply mkes it runnier and not any more like a wiping finish, it will lay down a very, very smooth coat. Like the poster before, I think the problem is in that foam brush. Try wiping the finish on with a clean, lint-free cloth, or use one of those staining pads from Home Depot. That should work fine.
And, FWIW, I have used 0000 steel wool and fine grit paper on the final coat when using this product, and it came out just fine. I wouldn't worry too much about that.
Arm-R-Seal is one of my favorite products. I find that I can get whatever finish I like depending on how I use it. I never use a foam brush to apply it though. I just cant control the flow. I use a soft cotton cloth, clean white old t-shirt or such. Fold it up and wipe it on. You can wipe over if you have too much finish. Work quickly, if it tacks up you are out of luck. I sand between coats, or sometimes every other coat, with the 000000 synthetic steel wool, or Micro-Mesh, somewhere around 3600 grade. If you want a really deep finish, use Micro-Mesh to finish sand the wood, even to 12000. Then apply many light coats of Arm-R-Seal. The key is light coats. The first two coats you will barely even know you have anything on the wood, because it will soak in and seal first. Then you start seeing some finish. Let it dry at least 24 hours between coats. I usually apply seven or eight coats if I really want a good finish. I don't usually have to sand the final coat at all. Let it dry a couple of weeks before you wax it. This is an oil based product after all. It's a great product if you use it right.