Basic Sharpening Tutorial

[Bob Smalser]

Bob,
Could you post a tutorial on how you sharpen? I use waterstones but hate the hassle of trying to keep them flat. I have my grandfather’s oilstones some maybe 50 or 75 years old (just guessing) I …would love to see your thoughts in pictures. [/quote]

Glad to help. I don’t use waterstones, but I did spend years using composite stones that also hollowed badly. There are a couple basic techniques you can use to minimize the hollowing. The first is to use the entire surface of both sides of the stone wherever you can…. not just the center…and the other is to do more on the grinder and less on the stone.

Using the entire stone sometimes means you have to forego some jigs, but it’s always good to develop your ability to sharpen freehand as I can think of dozens of situations in even hobby woodworking where your bench and jig won’t be available. All the grandiose words written in the last couple decades on honing, all the expensive gizmos for sale to help you do it, and all the trouble folks seem to have with it puzzle me some. Grind that blade correctly, and the difference in cutting speeds and technique between oil, water or composite stones is meaningless because there isn’t enough honing to be done to measure a difference. Moreover, why would I want to trade my hundred-dollar Taiwanese large pedestal grinder for a several-hundred dollar Tormek, when I hear the Tormek is slooooooowwwwwww….

http://pic3.picturetrail.com/VOL12/1104763/5090019/69053167.jpg

So I’ll go you one better on your question. I’ll convert an old abused, 2-dollar half-inch firmer chisel to a small skew for lathe work. Lotsa grinding required here…and on burnable 19th-Century carbon, not burn proof High Speed Steel. Get good enough freehanding on your stones, and it takes no longer to put your best edge on that carbon skew using stones as it does to put an inferior edge on an HSS skew using a grinder.

I mark the bevel I want on the chisel using a bevel gage and carbide scriber…

http://pic3.picturetrail.com/VOL12/1104763/5090019/69053176.jpg

…and grind off the old edge square to the line. Looking at the squared-up flat I made, the chisel’s old bevel largely remains on the bottom side in the pic, but the flat penetrates to at least the center of the bevel at the point of the skew to leave enough steel there to grind a perfect bevel and edge next. The objective in all sharpening is razor-sharp…but also consuming minimum steel in the process.

I’m using the coarsest grinding material I have…both my coarsest grinding stone and 26-grit sanding disks for the roughing work. The coarser the abrasive, the cooler it cuts and the faster you can do the job without stopping to cool the steel with every stroke. Remember that if you turn that steel blue with the 600 degrees it takes to do it, you’ve ruined its temper and all that blue must be ground off for that steel to hold an edge. Takes two minutes to grind.

http://pic3.picturetrail.com/VOL12/1104763/5090019/69053181.jpg

Next I grind the 20-degree bevel on both sides of the skew. I use the tool rest and the side of the coarse wheel in the 8”, 1750-rpm buffer-grinder. No jigs, no Tormeks, just that angle gage sitting handy on the grinder stand to show me what 20 degrees looks like when grinding either side….working all that out with the wheel stopped, of course. Takes 5 minutes, taking a little bit off at a time then dipping the tool in water and examining the cut for any adjustments in my hold required. The closer I get to forming an edge, the easier it is to burn the edge.

Learn to watch the trail of grinding sparks flying off the steel…. their density and quantity tell you precisely how much steel you are taking off and from where…showing you how uniform your resulting bevel will be.

http://pic3.picturetrail.com/VOL12/1104763/5090019/69053189.jpg

Here’s the ground edge.

http://pic3.picturetrail.com/VOL12/1104763/5090019/69053195.jpg

Now I take the skew to the coarse novaculite stone fresh from the can of kerosene it lives in and measure what 20 degrees looks like for rough honing. I’ll not use a secondary bevel on this edge but hone a flat 20 degrees on both sides. That stone was my uncles, who built boats professionally from 1930 to 1970…no telling how old it is but it’s just as clean and flat as the day it was ground. It may even have belonged to his father, a carriage maker.

Having taught a number of young people to sharpen over the decades, the single biggest factor in ease of honing is the height of the stone. Do what you have to do to get it secure and to the level of your belt buckle…higher than your kitchen counters, let alone most workbenches. This gets your elbows up and free from your torso to aid you keeping a consistent angle without any rocker or rounding.

http://pic3.picturetrail.com/VOL12/1104763/5090019/69053973.jpg

I dip the end of the tool in kerosene and make a few strokes on the stone…then I examine it to see what hold adjustments I need to make. See the flat? I need to drop the angle a tad and apply more pressure to the lower edge of the skew to even up that bevel.

http://pic3.picturetrail.com/VOL12/1104763/5090019/69053987.jpg

Pressure adjustments are made using the fingers of the left hand while I stroke the tool back and forth using my right. Here I’ve wrapped my fingers around the lower edge side to apply more pressure to that edge than the upper or tip edge.

http://pic3.picturetrail.com/VOL12/1104763/5090019/69053979.jpg

Now you can see I have an evenly formed bevel. Its not perfect…but as only a couple thousandths at the edge really matter, it doesn’t have to be. Takes only another 5 minutes, and if this were merely a secondary bevel on an existing chisel, it would have taken one minute or less.

With the bevel honed on both sides, I clean, buff and phosphate blue the skew before final honing. Cold blue or machinist’s layout blue applied to your tool before honing will teach you gobs about the effects you are having, as the camera picks up the small details shown better than the naked eye. Especially a 50+-year-old naked eye, and especially flattening your chisel backs…. do the rough work flattening backs …not on your expensive stones…but on your belt sander using 150 grit…just remove the bag and clean out the sawdust first.

Continued…

[Bob Smalser]

http://pic3.picturetrail.com/VOL12/1104763/5090019/69053997.jpg

Final honing is done on the fine novaculite stone. I have no earthly idea what grit or microns these or my black novaculite stone are…and don’t especially care. I do know the black stone, which I use only on the thinnest edges, will sharpen a straight razor or scalpel as well an anything I have ever seen. I also know you can’t judge the coarseness of these stones solely by their color…I have a fine stone darker in color than my coarse stone. Note the darkened kerosene on the stone…how uniform it is compared to the bevel being honed. Ground steel particles cause the color. Just like watching the spark trail while grinding, watching the fresh lube get dirty tells you how even your bevel is forming and where more or less pressure is needed.

http://pic3.picturetrail.com/VOL12/1104763/5090019/69054007.jpg

An evenly formed and flat, fully honed bevel ready for stropping. Took 2 minutes…about how long it should take you to hone the back and secondary bevel on a bench chisel.

http://pic3.picturetrail.com/VOL12/1104763/5090019/69054953.jpg

I strop using a stitched muslin wheel loaded with Knifemaker’s Green Rouge…there are many stropping mediums, and it doesn’t matter which one you use. What matters is stropping your bevel at the same angles you used in honing. I also use a hard felt wheel, but it removes more steel and gets very hot very quickly, and I use it primarily to quickly touch up my turning tools without any honing.

If you are stropping at the correct angle yet the tool is duller after you are done, your error is being made at the fine stone, not the strop. When you hone one bevel, you create a wire edge that is honed off when you switch to hone the other side of the chisel. If your hold and angles are inconsistent, that wire edge can be too thick…an edge that should have been removed on the stones rather than the strop, because when the strop removes it, it breaks it off deep enough into the edge to dull the tool.

The secret to long tool life is to take the 5 minutes it takes to touch them up after each day's use, keeping those honing angles constant and dropping the honing angle occasionally to flatten the main bevel as the secondary bevel wears. If you never round or rocker your edge.... you can go literally decades without grinding it again.

http://pic3.picturetrail.com/VOL12/1104763/5090019/69054966.jpg

The final result shaves dry hair painlessly…

http://pic3.picturetrail.com/VOL12/1104763/5090019/69054976.jpg

…and the finished skew. Total time including bluing and turning was less than two hours.

Proper sharpening can be done well in many mediums…my counsel is not to buy anything new but learn to use what you have. But I’m not your guy to ask about water stone grits, diamond paste microns, indexing plates or Tormeks…I only lust after the best novaculite stones ever made…Hall’s:

http://www.hallsproedge.com/history.htm
















“When we build, let us think that we build forever. Let it not be for present delight nor for present use alone. Let it be such work as our descendants will thank us for; and let us think...that a time is to come when those (heirlooms) will be held sacred because our hands have touched them, and that men will say, as they look upon the labor and wrought substance of them, ‘See! This our father did for us.’ “ --John Ruskin.

[jbranam39]

Bob great information thaks for posting.

[Sawduster]

Well, Bob, you convinced me. I just went over to that Hall's site and ordered me up a couple bench stones from them. My biggest issue with stones has been the PITA of them getting hollowed out and needing to be reflattened and since you and they claim these don't hollow out, I've no excuse now. The prices even seemed reasonable.

[Limey]

Jerry..
There is no "Holy Grail" Arkansas Stones WIll hollow if you don't make sure you are working the entire face of the stone...albeit it will be less rapid on a "hard" stone.
I prefer the more friable Synthetic Waterstones as they can be flattened very rapidly by rubbing them face to face or on a flatsuface covered with silicone carbide adhesive paper.
Jigs aren't all that bad as you can vary the angle of push imperceptibly by adopting a fan motion to cover the whole width of stone and turning it round from time to time.
I do a lot of sharpening and the original waterstones are now entering there 17th season
I've used a soft Arkansas for years as the final honing stage and must warn you that they gouge easily if you aren't careful.
I purchased a 6000 grit Waterstone when they were on special for around $20 and like it a lot.
Whether you keep the stones submerged in Kerosene or in my case water is a personal choice..I personally don't care for the smell of kerosene or what it does to my hands unless I don surgical gloves.
your experience could be different.

I'm not trying to downplay Arkansas stones as they will certainly do the job but just to point out that other systems work equally well if the downside of oils and kerosene don't appeal.


Limey

[Sawduster]

Don't know what I'll do about storing them, but I'm already using oil with the scarey sharp stuff, and I ordered some honing oil also. The site I ordered them from recommended cleaning them with soap and water after use, so I don't know that storing them in kerosine or some other light oil is a requirement. I probably ought to read up some more on that.

With all of the talk on another forums about flattening the water stones, I got the impression that that was a weekly chore or something. Until I started using scarey sharp, I was doing the hit and miss thing with different types and sizes of stones and didn't seem to be getting anywhere and was never happy with the results.

I've been pretty satisfied with the sandpaper system, but with as much as I'm sharpening lately with a bunch of new old chisels, a couple shaves and the growing arsenal of planes, good sized stones will pay for themselves in fairly short order. I've had a couple of small oil stones years ago that I used for knife sharpening, and I was happy with those, though they seem to have disappeared down the many twists and turns of life.

With all of the sharpening I've been doing lately I've used my couple of jigs only to grind the initial bevel and have taken to touching up the edge freehand at frequent intervals.

[Limey]

Depends on usage and technique of working to keep a flat stone obviously ....but I usually give the waterstones a rub together every 6-8 weeks and maybe once a year do a table flatten if I notice that the rubbing isn't working..then it is only the 800 grit stone which needs it as it wears less quickly against the 1200 and I refuse to take off more than necessary on the finer stone :).
The thing is ... once the 1200 is flat it will quickly get the 6000 or Soft Arkansas flat as it is the more aggressive of the stones.

The other advantage is that the clay of the waterstones don't tend to clog as easily and cleans out the embedded metal particles as you go ...I use the stones almost submerged so that the water washes the floating particles away before they embed.

Like you said about sharpening and not waiting till you need to do some heavy duty restoration equally applies to stone maintenance.


Limey

[Sonny Edmonds]

Nothing to add to this....
However, the same applied to your chainsaw chains will surely add to the chain, and powerheads, life. ;)

:D

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