# How much sanding is enough sanding?



## Mdreibelbis (Mar 26, 2013)

Okay - I'm seriously trying to up my finishing techniques - the bar has been set pretty low quite frankly.

So - I'm working on a project with some soft pine and wonder how to know when I've sanded it enough. I've given it a pretty thorough sanding with some 100 grit with my palm sander and plan on going to 150 then 220 by hand (paper wrapped in a block of wood) - but I feel like I'm just guessing on when enough is enough.

Also - when sanding with the finer grades (like the 220) do you normally do it by hand or do you use some type of power sander? 

And finally - does it matter how much time passes when you finish sanding before you apply stain?

Thanks!


----------



## Steve Neul (Sep 2, 2011)

I generally do all my finish sanding on flat areas with a random orbital sander. Once you've worked out a system of sanding it becomes instinctive when enough sanding has been done. Since you started with 100 grit and finished with 220 grit you are probably alright. If you had used 60 grit paper to get rid of a problem spot then much additional sanding would be necessary. The electric sander makes swirl scratches in the wood that doesn't show up until stain is applied. The coarser paper that is used the deeper the scratches it makes. When sanding, to be sure your sanding is completely effective each change to a finer paper you could wipe the wood down with a wet rag before making the change. By doing so it raises the grain and better sands the scratches the previous grit made. Wood is like a cluster of drinking straws and when sanding they get mushed down. Wetting the wood swells them back up so can be machined better. Raising the grain also makes a better surface if you plan to use water based stains and finishes.


----------



## Brian T. (Dec 19, 2012)

If the wood is smooth to the touch already, I would not start with anything coarser than 220. What for? Long, straight strokes, with the grain direction to avoid cutting any fiber. Then, I'd only have to sand more to abrade the scratches!. Sandpaper simply scuffs up the surface in an attempt to make it evenly scuffed, all over.
Scrapers don't work well on soft woods. After finishing, anything less than coarse steel wool is also a mistake. Coarse steel wool is flat. Like a million little chisels. Slices off all the prickly fiber.

In a soft wood carving (western red cedar) it is so very tempting to follow the shapes when sanding and not the grain. Wrong. Even with the carving tool marks, I'm only doing the legs/feet (24" x 3.5" x 3.5" caterpillar). Going around and around and around and around those things is exactly why I'm sitting here.


----------



## knotscott (Nov 8, 2007)

*"How much sanding is enough sanding?"*

Couldn't tell ya, because I've never gotten there! :laughing:


----------



## Rick Mosher (Feb 26, 2009)

The reason you sand is to make the surface flat and remove any scratches or dents. The only way to tell if you have accomplished that is to examine the surface with a bright light held at a low raking angle to the surface. Any dents or scratches will stand out and can be circled with a pencil. When all the defects are gone you are done sanding. 

The sanding grits are determined by a few things, wood species, finish schedule and method of sanding. If you are using an orbital sander you will be creating swirls and the smallest grit that won't show is 180. If you are block sanding then 120 or 150 with the grain is fine. If you are using a really hard wood like maple, 220 grit paper will actually burnish the surface and cause adhesion problems with the finish but on a softer wood like pine or alder 220 is perfectly acceptable. Also if you are using a water stain or water based finish you can sand to a finer grit because the water will open the grain back up and create better adhesion.

 I picked up one of these LED spotlights that I use to inspect the surface and it was only around $40


----------



## Midlandbob (Sep 5, 2011)

This is a complicated question with no simple answer. It would be best to get a good book on finishing.
How far to go with sanding depends mostly on the hardness of the wood and the type of finish you intend to use. Ease and cost can become important.
To simplify you are removing damage to the surface to get an even surface for your finish. Scratches and planer marks that are bruising of the wood usually need to be removed.
It is especially important if you are going to stain as stain will be very blotchy if you don't sand to a uniform texture.
There is little benefit in sanding softwood or hardwood that you will put a film finish on to more than 180-220 . The film will build on the wood and conceal any fine scratches especially if they are with the grain direction.
Hardwoods to have a penetrating oil finish and be touched will benefit from sanding to 400 or even higher grits. I would sand a table top to 400- 600 but the legs and apron to 220. The sanded surface is what you feel and finer is often better.
Have to go for supper.


----------

