Draw Knife Sharpening

Re: Draw Knife Sharpening

Dave Mount

>Depends on whether the nick is where it's going to bother you. It's obviously not going to be sharp wherever there is still a nick. If it's off to the side, it might not bother you.

When you say "jointing" the edge, it implies you mean straightening it as well -- straight is not necessary for sharp or for use.

Dave

Re: Draw Knife Sharpening

Howard Pollack

>How do you sharpen a draw knife? I've been wondering about that lately. Thanks -Howard

Re: Draw Knife Sharpening

Thom D

>Dave has it right, though it you had an uneven edge you might well multiply the difficulty of sharpening it.

One of the difficulties of answering the how to sharpen question is there are many different edge configurations on draw knives, and there are also different style of use. Unlike a lot of other woodworking tools, convex edge profiles are faily common, and for the these the easiest means of sharpening is on a belt sander, slack belt style. If it's modern that is probably how it was originally ground. You can also use a belt with a little slack in it scary sharp style.

For flatter bevels you can work them on a stone conventionally. The best control may come for working the tool by it's handles over a stone.

Re: Draw Knife Sharpening

William Duffield, on the Cohansey

>I agree. Nothing* works like a belt sander. Using just about any other method, the handles get in the way, and tend to disrupt the achievement of a consistent bevel. On a belt sander, they actually help, at least if you are sharpening freehand. Of course, your belt sander has to be narrower than the distance between the handles.

I recently acquired a 7" curved PEXTO shave with a "bevel" that was totally useless. Obviously, someone had failed miserably at an attempt to sharpen it. It varied between about 40� and 60� and was severely convex and faceted. Trying to reshape it on a powered grinder was what finally pushed me over the edge, and I acquired a belt sander. It also helped me to realize how the edge had come to that condition. (An article a while back by Derek Cohen on an easy to implement grinding jig for a cheap combo 4"x36" belt and 6" disc sander helped a lot to persuade me, too. I'm still working on my version of Derek's tool rest.) Reshaping the drawknife on an 80 grit belt was trivial. I refined a microbevel on both surfaces with a small diamond hone.

Note that I use my drawknife like I would any other carving tool, with a microbevel on both surfaces of the edge, because that allows me to make controlled, curved cuts either bevel up or bevel down. Thanks to Lee Grindinger for hammering that important point home, over the course of several discussions on the Carving Forum.

* If you want to maintain one using completely hand tool techniques, you should probably acquire an old, treadle-powered, wet wheel grind stone. It would work just as well as the belt sander. The problem with most of these is that when they were abandoned, they were usually left with water in the trough, which softened the bottom side of the wheel. This put the wheel out of round and out of balance, and getting them round again is a really major undertaking.

Re: Draw Knife Sharpening

Dave Thompson

>I agree with the points made in thread so far... though I've never tried a treadle-powered wet wheel grind stone, I like the idea.

Just wanted to say that for more discussion, FWW had an article on sharpening draw knifes. I don't have access to check now, but would guess it came out two issues back.

enjoy,

Dave

Alternative approach

Bob Hackett

>For those not willing to put out the money for yet another stationary power tool(the belt sander,which really is a good choice for alot of tasks)I`d like to suggest an angle grinder.

Think of an angle grinder as an industrial strength Dremel.It can be used for just about anything with the proper attachments and I fell it`s a good fit for any homeowner,carpenter,or WWer.

For this task I use an abrasive disc that looks like a flat flap wheel in 120-220 grit.sand with the wheel running off the edge(obviously) and a light touch.In less time than it takes to set up the grinder you`ll have the bevel shaped and ready to hone.

Remember to touch up the lawn mower blades before putting the grinder away.It is that season you know.

Mainely,Bob

Nicks Are No Big Deal...

Greg Betit, Vergennes, VT.

>The draw knife is rarely considered a finishing tool; removing the nicks isn't important at all. In fact it seriously shortens the life of the tool (as does the use of belt sanders and dremel tools on draw knives.) Almost every time you use the draw knife you will follow it with a spoke shave and/or scraper that will make short work of any signatures left by the nicks.

Greg

Re: Nicks Are No Big Deal...

Kevin Adams

>I agree with Greg here. Nicks can actually act like serrations on a knife or the toothed edge of a saw. As long as the edge is sharp (and you obviously don't want too many nicks), it can actually make the drawknife work more aggressively. I have several knives (as does Greg!) and while some are polished edges for close to finishing cuts, others have a few nicks for really getting after a piece.

Kevin

Re: Draw Knife Sharpening

Darrell in Oakville

>Nicks in a drawknife are not particularly bad, but it depends on how you use the tool. I have one drawknife that is kept VERY sharp, for finer work, and I keep an edge protector on it. The other drawknives are just mostly sharp, for rougher work like peeling bark.

As far as sharpening is concerned, I've found that the steel in my drawknives (Greenlees & Canadian Champion) are just soft enough that I can drawfile the blades with a good file. This GREATLY speeds up shaping a new edge when you don't have a belt s*nd*r. I clamp the drawknife to the edge of my bench and drawfile the edge. This is reasonably safe because my hands are not moving towards the edge being sharpened.

Darrell

Wood Hoarder, Blade Sharpener, and Occasional Tool User

Re: Draw Knife Sharpening

Ron Smith

>I feel sanders and grinders may be appropriate for sharpening rough knives for use on dirty or rough wood, such as barking. But use of such tools may yield marginal results, and will accelerate wear on the knife.

In sharpening a fine drawknife in already good condition I find the following approach yields excellent results. It is fast, safe, and provides a very sharp blade with consistent bevel angle:

Use one inch wide by 2 or three inch stones. I use the diamond stones in various coarseness. Lay the stone on the blade bevel and observe the unsupported stone behind the bevel. Now, select a piece of wood to be used to occupy that space. This may be a small wedge or simply a one inch piece of appropriately thich dowel stock. Trim this piece for a perfect fit to support the stones relationship to the blade. Grasp the stone AND the wedge and hold them securely in one hand. Lay the drawknife on your bench holding by one handle and angle the knife so the bevel is close to level. Now, begin flailing away at the blade with the stone. Hold the wedging device securely to the stone making sure the stone and wedge are pressed firmly against the blade. Take full length sweeps to assure consistent stock removal across the entire blade. Move then to a finer stone, and perhaps a polishing compound (I use the green stuff from Veritas . . . ground into a piece of hardwood) it will give you a chromelike finish quick enough. If you wish an additional bevel (front, or reverse of the blade) just select a slightly thicker wooden wedge, use your finest grit stone and repeat the grinding and polishing of the final bevel. One can draw the edge over a compound charged strop if a finer edge is desired.

This technique work perfectly on any large blade. I use it successfully on 10 - 14 inch butcher knives which I find extremely difficult to sharpen on the common 8 - 10 stones. Give it a try . . this technique may suit you.

Re: Draw Knife Sharpening

Jim in Burlington On

>Personally I use Bob's method as outlined in his article here. Only difference is I use a cheap carborundum oil stone to remove nicks and pitting then go to a finer oil stone and few swipes with a diamond stone then a couple seconds with a old 4000 water stone.