Whiskering

One of our members asked me about the difference between "whiskering" and "wet sanding".
After giving my opinion, I thought there might be others out there who are a little confused about these terms so, here is the answer I gave to him.

Whiskering is not the same as wet sanding.

As the builder sands the stocks wood, the sandpaper is cutting thru the walls of the woods cells leaving pieces of each cell wall behind.
These are quite happy to stay where they have been sense the wood was formed until they get wet.
When that happens, the unrestrained cells walls are free to move and many of them will end up sticking up into the air. Of course this makes for a rough poorly finished stock.
The idea of whiskering is to remove these tiny splinters of the cell walls that are sticking up.

To do this, after wetting the surface of the stock you must let the surface of the wood dry.
While the surface of the wood is wet, the little splinters of cell wall will be very flexable but after they dry they will be very hard and stiff.
Because of this, sanding while the stock is wet will do nothing except force the whiskers back down where they came from only to pop back up later when the woods surface becomes wet again from staining.
Many of us have found that drying the surface with a hair dryer not only speeds up the process but actually causes some of the tiny wood fibers to stick up more than they would have done if they were allowed to dry naturally. This by the way is good. We want to remove any fibers that are going to stand up later when we start staining.

After the wood is dry and the whiskers are sticking up the game plan is to cut off those fibers without sanding into and opening up the uncut cells. That is why it is important to use new sharp sandpaper and to apply only a very gentle pressure to the sandpaper.
It is also why we want to sand "against" the fibers that are sticking up. (This means sanding against the direction that the whiskers feel the "roughest".)

If we sand "with" the fibers, or in the direction that they feel smoother we will just end up pushing the fibers back down where they came from so they will end up sticking back up when the stain is applied.
Please note that this part of the sanding process is done with everything dry, not wet.

Wet sanding is usually done on metal parts or on the hardened finish products like varnish, oils, lacquer etc.
The purpose of wet sanding is to wash away the loose particles that have been removed by sanding so that they don't "clog" or "fill" the spaces between the "sand" grains. This keeps the sandpaper in a condition where it can continue to "cut" away more material.

There is a type of "wet sanding" that is done on wood. This is usually done on Walnut or other "open grain" woods where we want to "fill" the open cells of the wood.
To do this type of wet sanding (filling) first stain the wood (only if it needs it).
Then using a small amount of linseed oil or tung oil along with a piece of 220 grit sandpaper, lightly sand the surface of the stock. The sanding dust created from the sanding will mix with the oil and be deposited into the open grain of the stock.
This usually has to be done a few times to get all of the grain filled. When the oil hardens the surface will be smooth and ready for the application of the final finish.

Excellent treatise Zonie. I would only add that you may need to whisker the wood 2-3 times before it is completely smooth and whisker free. Emery

Thanks that's helpful to me.

Very nicely done! :thumbsup:

I agree that whiskering should be done 2-3 times before the process is complete, certainly with figured woods like fiddle back or striped Maple.

My experience with wet sanding is that it's done to "smooth down" a finish, to provide a smoother base for the next coat, as in sanding sealer or french polishing. I don't know that I would go much coarser than 400 grit for a wet sand.
My favorite method is spit and 600 grit, very carefully, to not "burn through" the stain.

All this time I've been whiskering with the grain. Thanks for the tip. Bill

Nice piece, Jim. I would only add that using a scraper to remove the whiskers is a good way to avoid sanding " too much", and leaves a very smooth finish to the wood, with no more whiskers to fight. Of course, you have to scrape " against the grain " of the wood to cut the whiskers off. This is the opposite direction of your stroke that you learned when you began to shave whiskers off your face. You shave WITH the grain of your beard, not against it. OUCH! :nono: :cursing: :surrender: :thumbsup:

Does it matter what you use to wet the wood before whiskering?
An old time stock maker I knew always used white vinegar for whiskering. I've also done a few with vinegar. Any advantage or disadvantage?

I've always whiskered with water, usually two or three times. The hair dryer can cut down the # of times it's needed.

Hadn't thought to try "wet sanding" with the finish, but I like the idea a lot. Anything to fill that open grain faster will be bonus points.

Great write-up for newbies!

You had me 'scared' there with your first treatise on 'west sanding' so I'm pleased to see you added the additional distinction of wet-sanding with an oil-type finish. I too find this works awesome on oil finishes on walnut stocks and I've done all my High Walls this way (on those that I've refurbished anyway, meaning not collectors).

One tip on wet-sanding of metals or other hard non-wood finishes, the paper should be in the water being rinsed more than it should be on the surface being worked. And if a large area, use a backer so you don't 'dish' the area.

Thanks for adding to the wealth of info here :thumbsup: !

Excellent information Zonie - many thanks. Three follow up questions tho.

1. I have heard of guys using steel wool and/or pummice stone for the de-whiskering. Any views on this?

2. For either you or Paul. Can you run through the operation of scrapers? I have heard I think that a scraped surface is more "authentic" than sandpaper???? and that it will take stains and polish better because the wood cells are cleanly cut as opposed to crunched closed as might be the case with sandpaper.

3. Do you know how to reproduce a classic "London Oil" finish on a stock? I have heard that at least one British maker uses a home grown product called "slackum" but what is in it or how it is applied I have no idea. I am betting, however, that it would be a wonderful finish for a muzzle loader.

Again, many thanks for the information :bow:

Best Wishes

Robbo

I scraped my first stock with an old boy scout knife black, stroking against the grain to just cut off the whiskers. It was many years later that I had my first true " scraper ", Frankly, I don't think it does a better or quicker job than my old knife. Now, I put a good edge on that blade. A scraper will be burnished on the edge to raise burrs on both sides. Its the burrs that are used to cut the whiskers off.

I anchor my hand at the butt, and use a whisk broom motion towards myself in short strokes, to remove the whiskers, without scratching the rest of the stock. I periodically blow the debris off the stock, so I can get a good, low angled look at my work, and see if I need to go back and work an area again before moveing elsewhere on the stock. Of course, the best test is the hand test, lightly rubbing the stock to feel if there are any rough spots.

Robbo:
Speaking of steel wool, my answer is, If you are going to use any stains which contain water, water + alcohol or one of the acid stains (vinegar or Aquafortis) after whiskering, don't use it.

Steel wool will leave tiny particles of steel embedded in the woods pores and the stains will cause these particles to rust leaving the most hideous little redish colored freckles you've ever seen.
I've seen this happen first hand and it resulted in my having to totally resand the stock.

As for scraping, if it is done correctly I'm not sure if it is any better than properly using sandpaper to whisker with.
If it is done incorrectly by scraping across the grain even for an instant it can cut small scratches into the wood that won't be noticed until you get around to applying the finish coats.

Scraping is an art that has to be learned from practice and it (IMO) is rather difficult to use on very curly woods.
You may be interested in following this link to an old post about scrapers:
SCRAPERS
As for "London Oil" finishes I must claim ignorance.
I can guess that it was probably Linseed oil based as Linseed was a common oil used either by itself or mixed to make many types of varnishes.
It may also have been a form of wax that was rubbed into the wood.

I always scrape with the grain.

I scrape with the grain and use deer antler to burnish, again with the grain. It will look like you have finish on the rifle before there is any finish on it.