Sharpening

Hi again: so I think I will start with my take on sharpening (which I keep trying to spell with an extra “n”).

Sharpening is easy, sharpening is simple, sharpening is an every day couple of minutes task, do not let anyone tell you otherwise.

I have this theory that sharpening used to be done by everyone themselves, everyday, until some clever person “invented” an “easier” sharpening tool or method. Then of course in order to sell it they need to imply or outright state that you are doing it wrong.

Well, My wrong method consists (mainly) of an ordinary 2 sided Aluminum oxide stone. So you can tell right from the start that I don’t know what I’m doing.

The basic hardware store 2 sided AlOx stone has a “coarse” side at somewhere between 200 and 300 P (or “grit”), and a “fine” side somewhere around 500 or 600. The Fine side is sufficient to make your blades sharp enough to shave with, in fact I rarely use the other side. (note: the stone used to sharpen scythes to razor sharpness is a 180 grit, getting that kind of sharpness is all in the flick of the wrist.)

I start with making a hollow grind on the bevel. making sure I maintain the bevel NOT with jigs,clamps or fixtures but with an adjustable bevel gauge, which we all have or need anyhow, once the angle is established you need never check it again. It helps to keep in mind that all cutting edge angles are a compromise between which angle is best for each type of wood and what the steel can hold without breaking. A hard wood like White Oak or Sugar maple requires a steeper angle than a soft wood like Basswood or Sugar Pine, just to prevent the hardness from chipping the edge. So we compromise and make tool angles somewhere in between. It should be noted that specialists like Patternmakers will have all of their tools at a shallower angle (sometimes as low as 20 degrees) because they are using Mahogany and Pine, And others like an Ebeniste (a person who works almost exclusively with ebony) will have theirs at a steeper angle(sometimes as steep as 35 degrees), or else the wood will crumble the edge.

For the Rest Of Us we will shoot for the middle range (or compromise) of 25 to 30 degrees for chisels and plane irons. So here we go: first I take a chisel that needs sharpening. this one has been sharpened (honed) too many times so it first needs grinding. (to re-establish the hollow grind)

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Until you are used to it I advise you to take a black magic marker and color the bevel black.

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then go to your Grinder and set your finger under the rest so that the middle of the bevel rests on the wheel.

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turn the grinder on and just tap it to the wheel and check that it is in the middle(do not move your finger to check, that finger is your gauge). Re-position your finger if needed.

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grind only on the coarse wheel, only grind out the middle, Use a very light touch, leave a line of black at the edge and heal. This takes less than a minute. If you don’t press hard you are done before it gets hot.

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Get out your stone, I only use the “fine side” and a little oil (I use PB BLASTER or “Marvel Mystery Oil” (my preferred honing oil), yes that’s an actual product, find it at your auto supply store, it’s red-ish and smells of cloves).

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Rock the tool until you feel where both the cutting edge and the heal are touching the stone. Feeling the heal and edge touching is the only gauge you need. Then move the tool in circles and figure 8’s and all over the stone, LIGHTLY all over the stone, briefly all over the stone, and you are done with the stone in about 15 seconds. Now you can shave your arm if you like ;P.

The Next time you need to sharpen you’ll skip the grinding and spend 15 to 30 seconds on the stone and be done with it. for end grain Pine you might want sharper, but for 90% of your work you will not need sharper. Unless you just LIKE spending all of your time sharpening.

be well, count your fingers, have fun;

K

PS: I usually do NOT touch the flat face of the chisel, if for some reason you must then use a fine diamond plate. the LIGHT touch of the bevel on the stone will take off your burr if you have one. However a heavy touch will Make a burr that might be a problem for you.

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