Sanding

[PeteM]

The author of a project book I'm looking at says he "dislikes sanding" but says . . .

I go through the complete schedule of 100, 120, 150, 180, 220, 320 and finally 400. Before finishing I will vigorously rub the entire project with a red, gray and finish with a white 3M pad.

That's 10 times over the piece. Seem a bit excessive to me. What do you think????

pete

[McRabbet]

Good thread! I'm a minimalist, too -- I rely on 120/150/180/220 for almost all hardwoods and use 220 only on hardwood plywoods. I may use more hand passes of 220 between early coats. The toughest sanding I ever had to do was to remove dust nits from a finish coat of Rock Hard Tabletop Varnish (16 SF of surface area) and then transpose it to a satin finish at the customer's request. I used every grit from 120 to 1200 with an ROS sander. It took hours, but it took care of the issue.

[Bas]

Originally Posted by Howard Acheson

Here is something I put together a few years ago.

Howard, this is great info. I never did much sanding beyond 220 to begin with, but that was out of laziness, not knowledge

Some woods are prone to blotch when stained, the typical solution is to first apply thin coat of shellac. Would sanding to a higher grit also help prevent blotching, or does it just lessen absorption across the board?

[mikeacg]

This thread has been a real learning experience for me! Just another reason to love this forum...
Scott - thanks for your heads-up on the Festool. I will check it out.

[Howard Acheson]

>> Some woods are prone to blotch when stained, the typical solution is to first apply thin coat of shellac. Would sanding to a higher grit also help prevent blotching, or does it just lessen absorption across the board?

As the article points out, sanding beyond 180 to 220 will actually promote uneven coloring particularly if you are using an oil based pigment stain like Minwax. Burnishing never occurs evenly so the absorption rate is variable across the panel.

In general, woods that are naturally prone to uneven coloring have a characteristic where the grain structure is variable causing some areas to be end grain. These areas absorb more coloring and lead to the figure or areas of variable coloring. Cherry, Pine, Birch, Beech are woods that are most problematic.

However, let me say that the super craftsmen like Thom Moser, Sam Maloof and others never worried about uneven coloring. They considered the variable figure in cherry to be perfectly natural and they highlighted it. I visited the Thom Moser showroom in Maine a couple of weeks ago and all his high end furniture had variations of coloring even though none was stained. It's mainly the manufacturers of consumer factory furniture and kitchen cabinetry that uses techniques to "even out" cherry coloring.