Edited to add some notes for plane restoration and for further free hand instructions and clarifications.
I use an 8” aluminum oxide wheel for my bench grinder.
And yes I’ve put the cover back on.
I can still burn a blade if I’m not reasonably careful, but It works fairly well. I like the 8” wheel because the hollow in the bevel is smaller, making for a stronger edge. I also made this bench guide similar to one in one of Krenov’s books. I simply use wedges to adjust for different angles or thicker blades.
The wedges are marked so I can get back to the place I need to be. Flat without any wedges is 25 degrees.
Note, you can also hollow grind on a belt sander, if you want to try it before buying a grinder, or you just don’t have space for a grinder and you already have a belt sander.
The slot serves two purposes, a place for your fingers to slide, and you could make a guide if you have problems keeping the blade square. I made some square cut marks for references and that’s all I need.
If the cutter is from a plane restore, re-grinding a cutter is just a matter of taking a few more passes on the grinder were needed. Keep a square in your hand and check it as often as you need to. I always keep a gauge to check the angle to. Since this is a make shift angle jig it’s prone to getting moved on me sometimes.
I typically take 4 or 5 strokes, a dip of water between each (or almost each pass), then step to the extra course DMT to work on the back. Yes, I know I’m not finished with the bevel yet. I have 2 sticks on the bench, one about 1 1/2” wide and one just shy of 2”, about a foot long that I use to hold on top of the cutter while flattening the back. Use the one slightly narrower than the cutter.
Just back and forth for a few strokes ( 30+\- depending on my mood) while pushing down on the stick, then back to the grinder. I do the back and front rotation thing so the grinder doesn’t burn. I tend to be impatient. (note for cutters that have a really out of flat back, or some pitting, I will often start on a belt sander)
Once the edge is square and I have a burr, (some don’t wait for the burr, but I always do) and the back is flat on the extra course stone then I hit the hard Arkansas. I do the back first. Its already flat, so a few strokes to get it smooth. I then polish it on a felt wheel.
Then back to the Arkansas, Set the hollow ground bevel on the stone with your pointer finger of each hand on the front, pushing down hard. Rock it forward and back and hear the click. Forward and back until you know its sitting flat. Click front, click back, shorter and shorter forward and back movements until its down flat on the stone. Now pushing down so hard with your pointer fingers it hurts, then slide the cutter forward, using the sides of your hands. Now pull it back. Eventually you will see you don’t need to push down so hard it hurts, but keep it up until you feel comfortable that you can keep it flat.
Now, to round the corners you’ll want about 10 strokes with pressure on one side and then the other.
This is why I don’t care for a jig at this point. Let say you’re grinding at 25 degrees, you need the jig set at precisely 25 degrees. What if one is 25 1/2 degrees? It has to be perfect. Without the jig, minor variations are indifferent.
Now pull the back across a strop. I have one of Red’s that works great, but even a piece of brown paper bag will work. I don’t usually use any compound, but you can if you want. Paul Sellers recommends 30 strokes. I don’t think you need that many. 10 is good in my book. Keep the back flat, this is important. Now the front. I just pull it by eye. Its better to error to far back than to far front. To far front can round the edge. You just want to strip the burr if any is left and possibly polish the face, but it should already be pretty close.
If I’m in a hurry and resharpening, I’ll sometimes just drag it across the palm of my hand. Yes be careful if you decide to try it, but it works!
Also just touching up on the strop can help prolong between sharpenings.
a few notes
—I use a mixture of Diesel fuel and mineral oil in a spray bottle with the oil stones.
—Note for equipment I’ve used a grinder (something every shop should have)
—A good wheel. (I think mine is 120 grit)
—An extra course DMT (any course stone or sandpaper will work)
—I use dollar store window cleaner (I don’t know the chemistry of it, but dollar store window cleaner uses cheaper chemicals that coincidently helps against rusting the plates)
—A hard Arkansas stone. A good fine waterstone will work if you prefer water stones.
—A felt wheel for polishing. I run mine on an electric motor, but one in the drill press will work as well. Green or red compound. If you really don’t want to bother with a felt wheel, just some extra work on the strop with some compound will work as well
Here is the fine Arkasa stone. ($15 at a flea market)
And no I’m not suggesting equipment like the Tormek doesn’t do a nice jib, I am suggesting you don’t need them if you don’t have that kind of money or just don’t want to spend that kind of money. Plus my technic is quicker.
-- http://timetestedtools.net - Collecting is an investment in the past, and the future.