Lots of good advice here and I won't argue with any of it -- but I will state my opinions and preferences.
-I don't like fillers on porous woods -- I find they alter the color and appearance of the grain.
-For first sandings through 220 grit, use a "random orbital sander" -- not just an orbital sander.
-I will complete sanding at 320 grit (by hand with the grain). I like the effect on the appearance and it's a great prep for the actual finishing steps. I don't want my finish work to obscure the original look of the wood.
-I can also recommend the Minwax wipe-on poly -- use gloss until the final satin coat. It's excellent, it's fast, it's reasonable in cost, and you don't have all the custom mixing. If you're going to use 0000 grit steel wool, be sure you practice with it and know what you are doing.
-This IS slow work. Don't be afraid to wait a day between finish steps. Use a light scuff sanding between days at a grit equal to your highest.
-Vacuum the surface for dust -- don't just use a tack cloth. Better than a treated tack cloth is the "velour" style non-treated "tack cloths" (no residues).
A nice option for black walnut is a base coat of blonde shellac to preserve the natural color tones and begin filling those pores. The added layers of wipe-on poly will complete the fill without damage to the color and appearance.
I would recommend stopping work on the large "desktop" and work on a smaller "lap table" size piece until you feel confident with the work you're doing. With any technique (wood, sanding process, finish, etc.) that is new to you, practice first with a sample piece.
In addition to my work with black walnut, I've found these techniques to be very effective with red oak tabletops which are MUCH more porous than the black walnut. The result is a hard, lasting finish with a beautiful, natural look that may have a moderately textured feel, but is durable and flat.
None of this will result in a "French Polish" -type look or feel. But if you should want that at some point, I highly recommend some of the "flattening" the techniques alluded to in this thread. They are clearly defined in Flexner's excellent book on finishing.
Rich
-I don't like fillers on porous woods -- I find they alter the color and appearance of the grain.
-For first sandings through 220 grit, use a "random orbital sander" -- not just an orbital sander.
-I will complete sanding at 320 grit (by hand with the grain). I like the effect on the appearance and it's a great prep for the actual finishing steps. I don't want my finish work to obscure the original look of the wood.
-I can also recommend the Minwax wipe-on poly -- use gloss until the final satin coat. It's excellent, it's fast, it's reasonable in cost, and you don't have all the custom mixing. If you're going to use 0000 grit steel wool, be sure you practice with it and know what you are doing.
-This IS slow work. Don't be afraid to wait a day between finish steps. Use a light scuff sanding between days at a grit equal to your highest.
-Vacuum the surface for dust -- don't just use a tack cloth. Better than a treated tack cloth is the "velour" style non-treated "tack cloths" (no residues).
A nice option for black walnut is a base coat of blonde shellac to preserve the natural color tones and begin filling those pores. The added layers of wipe-on poly will complete the fill without damage to the color and appearance.
I would recommend stopping work on the large "desktop" and work on a smaller "lap table" size piece until you feel confident with the work you're doing. With any technique (wood, sanding process, finish, etc.) that is new to you, practice first with a sample piece.
In addition to my work with black walnut, I've found these techniques to be very effective with red oak tabletops which are MUCH more porous than the black walnut. The result is a hard, lasting finish with a beautiful, natural look that may have a moderately textured feel, but is durable and flat.
None of this will result in a "French Polish" -type look or feel. But if you should want that at some point, I highly recommend some of the "flattening" the techniques alluded to in this thread. They are clearly defined in Flexner's excellent book on finishing.
Rich