Episode #5: Sharpening – Part 1

Note: All of my old podcast videos have been moved to my YouTube channel.  You can now watch this video here:

https://www.youtube.com/watch?v=ge4PsKYl5XY

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13 thoughts on “Episode #5: Sharpening – Part 1

  1. Hey Bob,

    Very nice tutorial on sharpening straight edge tools.

    I must admit that I have tried the free hand method before but not had great results. So, I have used a honing guide for a while now. The rocking motion with arms locked to your body is something I’ll have to try. That looks like the “key ingredient” to success with this method.

    I’d be interested in your methods for narrow chisels (i.e. 1/4″ or 1/8″) with the free hand method. Those were always the hardest for me to do well with.

    • Mark,
      No shame in using a honing guide. If that’s what works for you then stick with it. What’s important is that you can get your tools sharp. If you do decide to try it, locking your arms and moving from your knees is a big help, but the hollow grind is actually more of an aid. It’s much more difficult to keep the bevel registered flat to the stone with a flat grind. As for the smaller chisels, I do them the same way. The key is to focus on the pressure being applied by your lower hand (my left). If you try to move the tool with your top hand you will have a tendency to roll it. Move the tool with your low hand and you avoid this. It takes a few minutes of slow going to get the feel of doing most of the work with your lower hand but once you get the feeling, it becomes easy to replicate.

  2. I’ve always used a Veritas MKII honing guide and will do a primary and micro bevel on my chisels using the guide. Last week I picked up a Hirsch mortising chisel on clearance at the Lee Valley Store in Halifax. Someone had returned it after banging up the edge quite a bit and the back was poorly lapped. What they did do though, that I had never tried was to hollow grind the bevel. So last night I decided to clean up the chisel and put a keen edge on it. I was very surprised at how easy it is to sharpen freehand when the bevel has a hollow grind to it. Time to invest in a slow speed grinder, or a hand cranked grinder (where did you ever find that thing, it’s awesome!)

    • Jason,
      Invest in a slow speed grinder or a hand crank if you like but they are really not necessary. I used a cheap imported Home Depot special high speed 6″ grinder for years before getting my hands on the hand crank. The “secret”, if you want to call it that, is to keep the grinding wheel dressed and not let it glaze over, cool the tool frequently in water if it starts to get hot and work slowly with a light touch on the coarsest wheel you can get. Coarse wheels cut faster but also cut cooler. A light touch is necessary to keep the wheel from glazing too quickly. If you do want a hand crank grinder, they are all over Ebay. Just make sure you get one that can handle at least a 6″ diameter wheel as that is the most commonly sold size.

  3. Half an hour of pure gold…..
    It’s only taken you five episodes to develop a very relaxed and natural style of delivery.

    I found your explanation of chasing the burr especially enlightening.
    Have you found that working with the long edge of the stones parallel to the length of the bench is better than having the stone perpendicular to the bench?

    Looking forward to the episode on curved edges – I’ve been having trouble with honing a jack plane iron that I radiused to try and prepare some very rough sawn stock.

    • Thanks Simon! I do find having the long edge of the stones parallel the front of the bench to be easier because I move from my knees, not my arms. If I were to hone front to back, I would have to move from my shoulders and elbows which, while a perfectly acceptable way to do it, doesn’t work as well for me because I cannot lock my hands and arms to help maintain the bevel flat to the stone.

  4. Good stuff. When you sharpen quickly during work, are you just using leather with honing compound or do you start with your finest stone?

    • Ben,
      Where I start with the re-honing depends on the tool and what I’m doing with it. If I’m just using a chisel to pare with, I’ll stop and strop it frequently during use. But it will get to a point where stropping just won’t renew the edge enough, then I go back and start with my first (coarsest) stone to raise a wire edge and then progress through the other stones and the strop. With planes and chisels I’m chopping with, I always start with the coarsest stone to raise a new wire edge as the edges are simply too dull for a strop alone to bring them back. However, I don’t regrind every time; only when the hone at the edge and heel of the bevel meet in the center.

  5. Love your blogs and pod casts. After watching this one went out an got the green honing compound…amazing, that’s all I can say. I always got close with my sharpening…but never like this. Thanks.

  6. Hi Bob,
    I love your podcasts. I have watched most of them several times. If you don’t mind, I need a little advise. I wore out my coarsest waterstone trying to flatten a plane iron. Thinking it would be more durable, I purchased a Pinnacle washita oil stone. It seemed not quite as coarse as the waterstone but pretty coarse. I put some oil on it and started lapping. It seemed to work okay at first but soon became very smooth and stopped cutting. Am I doing something wrong? I eagerly await more content on your website. Keep doing what you’re doing. Thanks.

    • You may have clogged up the stone with the lapping. Natural oil stones, especially the coarser ones like good soft Arks and Washitas can be very porous. You need to fill those pores with something to keep them from clogging. Contrary to popular belief and writing, the oil is not a lubricant, it’s used to fill the pores in the stone and keep the steel particles floating instead of getting into the pores of the stone. If you didn’t use enough oil, or if the lapping process wiped the oil from the top of the stone, the pores of the stone may have filled with steel particles. You need to use a lot of oil on the coarse stones and lapping large areas of steel removes a lot of metal so you need to clean the stone and re-oil frequently.

      In addition, natural stones tend to “wear in” after some use. Many will start out very aggressive and get smoother cutting as the stone is used. This is because, being a natural stone and not abrasive particles in a binder like a man made waterstone, the very sharp edges of the stone tend to fracture, leaving a smoother, less aggressive surface. New “grit” is not constantly exposed like in a water stone that constantly releases particles from the binder. Softer natural stones like soft Arks and Washitas also will wear much faster than a hard stone, so they need to be flattened occasionally, just like a water stone. This removes any dishing and restores the cutting action of the stone.

      You can likely restore the stone by first cleaning the pores of any steel residue and then flattening it on some silicon carbide sandpaper. To clean, first try simply flooding the stone with oil, or soaking it in something like kerosene. The oil needs to get into the pores of the stone and loosen the steel particles. A stiff nylon bristle brush may help loosen stubborn clogs. Once the majority of the steel has been cleaned out, use some 220 grit silicon carbide sandpaper (the black kind used for sanding metal) on a flat substrate to flatten the surface. This should clean the remainder of the stubborn clogs, reflatten the surface of the stone, and renew the cutting surface. It will take a little time and go through a little more paper than flattening a water stone, but you’ll get there. The benefit of a longer wearing stone is also a drawback when it comes time to reflatten. Maintain your softer stones frequently and you’ll spend less time each time.

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