Finish Process - James Holland
My finish process is a lengthy one, but is the best method I have found to produce a coat of "glass" on my work.

This process may or may not include walnut oil. Most times I use that oil when I want to make the colors of the bowl more rich. It seems to darken a slight degree the wood and enhance the appearance. But using oil and subsequent permanent finishes is not a good idea.

To use the oil effectively, you have to "burn" it in and harden it. To do this your work must still be very securely mounted on the lathe. You apply liberal amounts to your piece, then take a strip of felt or cotton, folded over 2 or 3 times and hold it on the bowl as it spins. 

This induces friction, heating up the oil, and drying it. Walnut oil is the only oil that will form a hard waterproof shell when it cures. Buffing it this way is a shortcut to doing this. However there are two drawbacks. One, the heat may cause your piece to warp undesirably. Two, walnut oil does not have much of a shine. Its a satin sheen at best.

Now, my method of producing a glassy coat to my work.

After sanding up to 400 grit, this is usually enough to look very nice. My next steps take place on the lathe as well. I use Deft spray laquer, or "clear finish sanding sealer"  and spray it on the piece as it spins. be sure you cover or make a cover for your lathe bed. I made one from scrap plywood that fits in the ways.

You will see the piece change color as you coat it properly. Let it continue to spin for 2 minutes. This is all it takes for the laquer to dry completely. Stop the lathe and check the piece for runs that may have occured from centrifigul force. They usually occur on end faces, so spray lightly on the bottom of your bowl if it is exposed. Sand the runs smooth. 

You should not have any runs along the sides of the bowl. Spraying while the work spins ensures an even coat.

Now, take a strip of felt cloth 1" wide and 12" long, hold the ends, and apply it with LIGHT PRESSURE to the work as it spins. Dont press hard. If you generate too much heat, it will peel small strips of the laquer off of the work onto your strip. Then you will have to sand the work and start over.

If you are doing it right you will see a high gloss appear on your work as you do it. Dont stay in one spot longer than 2 seconds. Keep the strip moving.

When you have a good reflection of light from all the sides of you bowl, stop the lathe and inspect it. You should see a nice glassy shine. Look for spots that soaked up the laquer that do not shine. Spot spray these spots, LIGHTLY, with the laquer. Turn on the lathe and dry it. 

Now turn off the lathe and check them again. If they continue to soak up the laquer, continue to spot spray these places until you see the grain start to seal. When you see that the wood has stopped soaking up the laquer and it has an obvious coat of laquer on all the surface, you can polish again with the felt strip.

Inspect your felt strip first. Look for tiny streaks of brown on it. This will be laquer that came off of the bowl. DONT use that part of the strip any more. Use another spot or the opposite side of the strip from this point on. 

Now you can do a light buff on the entire piece again. Try to bring the entire surface to a uniform gloss. 

Stop the lathe, check the piece and your strip. If your strip does not have clean areas to polish with, get a new strip. Check your work. If you have deposits of laquer in dull, brown streaks on it, you will have to back up and sand this off using a lot of fine sandpaper to remove it, then go thru this process again. The trick is to only apply light pressure and keep the strip moving.

Now, if all is good, you can spray a full coat on the entire piece with laquer, while it spins. As with the strip, only spray one second on any one spot. Too much and you will get runs that spin off from the force of spinning. 

Let it continue spinning and dry, about 2 minutes. 

Stop the lathe and check to make sure it is dry. This is critical. Make sure it is dry before you polish it with the felt. If its completely dry on all the surface, polish it to a gloss, then stop and inspect.

If all is well, put a final 3rd coat of laquer on, and repeat the process. This step is the most critical. Since you have several coats of laquer on the work now, it is much easier to get it too hot polishing, and ruin the coat. I have a 400w flood light on a utility lamp that I place shining on the work as it spins at this point, to assist in drying the laquer.

I would let this 3rd coat spin at least 10 minutes, with the light on it. Longer without a light. 

After this the laquer should be hard. Remove it from the lathe and if you have a place that the sun is shinning on, let the work stand in the sun for 15 minutes on each side. The UV rays will cure the laquer. To be absolutely sure it is cured, dont handle it for at least 3 hours. Work on another bowl or something.

After this cure time, feel the bowl, press on the surface with you fingers and make sure it is good and hard in all places. If you see any places that take on distortion from your fingers, let it cure overnight.

By this time it should be hard as a rock. Now you can remount the piece, and lightly polish it with clean felt. Again, dont let it get hot. Keep the felt moving. You can apply as much pressure as you need to see a good shine come out, but dont let the strip stay still in one spot.

You should have a very brilliant gloss now.

At this point, you can spray your first coat of spray polyurethane on your piece as it spins on the lathe. It is important to only fog your piece. If you spray too much, it will surely run. Poly is heavier than laquer. While you fog it, you will see a difference in the surface appearance. Use this as a guide to move your spray along the work.

When you have it coated, stop the lathe, and fully inspect the piece for runs. If you see any, take your finger and while moving the chuck with your other hand, smooth over the run while it is still wet. When you have all irregularities smoothed out, turn the lathe back on and let the piece spin. 

How long is up to you. The poly will cure on the outside surface, tacky to the touch, in about 15 minutes. Its at this point that I take the piece off the lathe, and place it in the sun. Sunlight does a very good job of curing poly.

All subsequent coats of poly are applied using my record player. I do this because it spins very slowly, and I can get a good thick even coat on the piece. The other reason is the piece is standing right side up instead of on its side. So if I do get a run, its much easier to sand down and repair. But normally using the reocord player, I can put 3 coats on the piece in one day provided it is at least 65 degrees outside.

If I cant keep the piece outside on my porch, where my record player is, then I spray it on the player, then bring it in the house and set it on a table that has sunlight coming in on it. I rotate the piece a quarter turn every 30 minutes.

Thats it.

This is a long process, but, once you are used to it, it only takes a few minutes for each step, and you can set it aside and work on other things as you wait for the different stages to cure.

When you are done, your piece looks like it has a layer of glass on it. Normally you dont have to polish the poly. But you can if you desire. Just be sure you polish, dont rub or generate any heat.