shooting for smoothest possible finish on wooden handles

[overmodulated]

Folks: am hoping you will share any tips you may have on achieving a "glass-smooth" handle finish. A couple related questions:

Is it advisable to buff the handles before, or after, applying coat(s) of tung oil? I assume a clean buffing wheel is needed here with no rouge.

Does anyone else have trouble with black-colored wet-dry sandpaper discoloring the lighter colored woods (like maple)? I usually end up smudging the wooden surface and can't keep it clean. Haven't been able to find very fine sandpaper (600 grit + higher) without the black background color.

Any guidance? Thanks so much!

[Fe-Wood]

Let me start off by saying I haven't made any knife handles but I have done a lot of hi gloss finishes on many varieties of wood. There are multiple factors that go into achieving a good quality high gloss finish.

One of the main factors is whether it is an open grain wood like Oak and Mahogany or a closed grain wood like Maple or Ebony, then there are the in-between woods like Cherry and Walnut.

After a "rough sanding" say 220 grit. The First thing one needs to do is stabilize the wood fibers. There are many ways to do this. Linseed Oil or Tung Oil (mixed with Mineral Spirits) is one way. Penetrating Epoxy is another and Diluted Lacquer or Shellac are others, there are others but these are the ones I've worked with. The goal is to get the hardening properties of the finish to penetrate into the wood fibers. Some are better for wet locations than other.

The next step will be "Filling" the pours of the wood to achieve a perfect, blemish free finish and so you don't discolor the wood with what ever you are using as the abrasive. I have been working with UV stabilized Penetrating Epoxy because this does both in one application and is a very durable finish.

Then you want to "build up" the finish. This give you something to Polish. Thats when you will use the super fine sand paper with water or mineral spirits as a lubrication- depending on what type of finish you used for the build up. Be VERY careful not to cut through the built up finish when sanding or polishing! The goal here is to build up enough material to work with while not discoloring the wood. Very few if any finishes are truly clear.

The last step is the actual polishing. I use a clean wool buff and a good quality carnuba wax.

This is a very brief description of a furniture quality, closed pour, high gloss finish. While using this overview as a guide and some experimentation from you with the materials you have, I think you will achieve the results you are looking for. A good finish takes time and elbow grease.

If you give me specifics of what you are using or can get easily, I will try to help you put together a approach to start with.

Good luck and us good ventilation and an organic chemical rated respirator- some of the finishes mentioned above are very toxic in the uncured form.

[BIGGUNDOCTOR]

Why do you want a glass smooth surface?

Personally I would want a little grip to them.

To keep a glass smooth surface I think that you would need to apply a hard coating like a polyurethane finish, or use stabilized wood. Wood grain will move with the humidity changes, so it won't stay glass smooth forever. High end gunstocks use dense wood to begin with, then use various products to seal the open grain that remains. You might want to try Tru Oil from Brownell's. Apply a few coats with 0000 steel wool scuffing in between, and you will get a smooth finish.

As to the sandpaper, no I have never had that happen. Is it a good brand of paper, or cheap import stuff.

Duh, just looked at what forum this was posted in, I thought you were talking about hammer handles, not knife handles/scales. :rolleyes:

[HWooldridge]

Black sandpaper is likely silicon carbide, which is not intended for wood. I've done gunstocks with 400 grit AO paper followed by 0000 steel wool and gotten them quite smooth but I use a damp cloth to raise the grain then flash dry with a propane torch (which also has a tendency to burn the little hairs). Just keep doing that until the grain no longer raises. As BigGunDoctor said, Tru-Oil works pretty well and will polish up to a mirror finish if you spend the time to do it right.

[overmodulated]

Great tips from all so far - thank you.

Perhaps the glass smooth reference was overstated. I wouldn't want a surface that would peel or crack. But I see some posts of people's work, some using the same wooden material I've chosen, and I'm impressed with the finish they've achieved.

So far I've used walnut, birdseye maple and maple burls, bloodwood, brazilian cherry (leftover scraps from my hardwood floors) and am now trying to do the right thing with an amboyna burl I recently purchased off the internet.

My only coating so far is tung oil (very thick stuff, which I cut with at least 2 parts mineral spirits). The sandpaper is the stuff sold at Home Depot (Norton), and it discolors all the lighter material because of that black backing. This makes me hesitant to work with the ultrafines, and I'm sure that's part of the problem.

[Fe-Wood]

If you use 320 Aluminium oxide that is well worn, you will be using something on the order of 600 grit. Mirka is the brand I like http://www.mirka.com/, you can get it at auto finish and cabinet hardware supliers, or on the net. Another good and easy finish to apply is a product call "Good Stuff" http://www.mapleblock.com/detail/butcher-block-finishes-39/

You put it onlibrally let dry a little and buff off.

[Rich Hale]

Any knife supply place will sell you wood that has been stabilized. The product goes all the way through the wood and when you sand it smooth and buff it is done. If you ever scratch it you sand out scratch and buff. Some really hard woods will not stabilize as it cannot get inside. I buy from K and G in Lakeside AZ.

[Karl]

I once read a book on knife making called Knifemaking: A Complete Guide to Crafting Knives, Handles & Sheaths written by Bo Bergman who specialises in making Sami knives. Unfortunately i cant remember the exact steps he used when finishing his knife handles but I'll give you a general idea and maybe someone else who's read the book and correct me.(also I've put a link to the book on amazon so everyone knows what I'm talking about)

Anyway basically the author said that for the best possible finish, once you have sanded the handle smooth(600g or 480g should be fine enough)
The next step is to soak the timber in warm water, wait for it to completely dry and then rub it down with steel wool until it's smooth.
the idea is that when the timber gets wet all the fibres on the surface will stand proud, when they dry the will harden in that position and then you can shave them off with the steel wool.
But you wont get it perfectly smooth first time so it needs to be repeated. i think the author said he would do it 3-5 times.

for coating the handles the author used a mixture containing equal amounts of linseed oil and gum turpentine.
he would rub this mixture into the timber until its saturated, then he would leave it for an hour or so and rub more of the mixture into the timber until was once again saturated.(this was repeated a few times as well)

The coating will take around 5 days to be fully cured but at the end you will have a stunning finish which is also completely waterproof and you can still feel the timber when you hold it.

I hope this is useful

Here's the link for the book
http://www.amazon.com/Knifemaking-Complete-Crafting-Handles-Sheaths/dp/188737437X

[sandpile]

Raise the grain and sand back till you get it where you want it, oil and seal and
wax till the handle is water proof and Simoniz or something similar on the carbon blade.

I use nose oil on my EDC O1 personal knife blade.

Lots of ways of getting there but no short-cuts just elbow grease and experiments.

None as easy as buying stabilized handle material.

chuck

[bigfootnampa]

Tung oil is a poor choice for getting very smooth surfaces. You would do better with a harder finish and preferably one that will mostly soak into the wood... a hard polyurethane that has been thinned would serve your purposes much better than any tung oil finish. A satin surface is about the smoothest that you can get from ANY type of oil finish... for knife handles the oil finishes have pretty poor protection against moisture and staining besides. A top grade acrylic or polyurethane would be FAR better for your purposes.

[jimbob]

after you sand it take bone and rub it all over then apply your finish