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rrich
27th November 2016, 07:03 AM
How I Sharpen Chisels

Is it the correct way? I'm sure that it is not. I'm sure that other methods work great but this is what works for me.

First flatten the back using the scary sharp method.
(Plate glass, wet or dry sandpaper glued to the glass, start with 100 grit and progress to 600 or 1200 grit.)
Use water stones to continue flattening the back from 800 to 6000.

Use a Tormek to put a hollow grind at a 25° to 30° bevel. The softer the steel the greater the angle.
Grade the wheel with the stone and finish the bevel.

Use water stones from 800 to 6000. Rock the heel of the bevel to the toe on the stone and about three, maybe four passes drawing the chisel heel toward you. As you progress up the grits, the wire edge from the previous grit will roll off. Using the water stones will give two shiny bands across the bevel. This is not a micro bevel. These bands show where the chisel was in contact with the water stone. When these two bands come into contact with each other, it is time to go back to the Tormek wheel.

Only as I'm using the chisel do I use the leather hone on the Tormek. As the chisel starts to lose its edge, I'll go to the hone wheel. This can be done probably 8 or 10 times. Then back to the water stones for a fresh edge.

Why flatten the back of a chisel?


This obtuse but if you follow, you will understand.

Go to your favorite adult beverage package or bottle shop. Ask for the corrugated shipping cardboard box that normally contains 12 bottles of the 750 ml size. Additional contents of the box at your discretion. Take a piece of this cardboard box and slice it on an angle across the grain or corrugations. Look at the edge along the slice. This is a large model of what the back of a chisel looks like from the factory. It all depends upon the final grit used in the manufacturing process. The finer the grit used on the back, the smaller or finer the scratch marks. It also shows why a chisel should be sharpened in the direction of the chisel and not across the chisel.

AlexS
27th November 2016, 07:39 AM
Rich, there are probably dozens of ways of sharpening chisels & planes, and they all have one thing in common. The people who use each one reckon that theirs is the best. In fact, most work well, and if anyone's happy with their method, it's the best method for them.

My method is very similar to yours, with a couple of minor differences.
Flattening the back: With a new blade, or one that hasn't been sharpened for a while, I flatten the back on a diamond plate. During sharpening, I do the back on each grade of water stone (800, 1600, 8000) before doing the bevel.

Honing: I've never used the honing wheel. Instead, I use a strip of leather impregnated with the honing paste that comes with my wet grinder. If necessary, I will freshen it up with some machine oil. Again, I hone both sides. Like you, I'll go back to honing, sometimes after touching up on the water stone, several times before I need to go to the wet grinder again.

Otherwise, our methods are virtually identical (but mine's the best :D).

Cliff Rogers
27th November 2016, 07:51 AM
What is wrong with using the concrete step just outside the roller door of my shed? :think:

NathanaelBC
27th November 2016, 08:03 AM
I hone mine on the rubber sole of my shoe impregnated with metal filings from the workshop floor.

Gives my work a nice textured surface.

When it calls for it I'll lap the face of them on my bench grinder.

Cliff Rogers
27th November 2016, 09:32 AM
I'll get photos next time they are blunt enough to need sharpening again.

Uncle Al
27th November 2016, 09:32 AM
What is wrong with using the concrete step just outside the roller door of my shed? :think:
Well, being 2,600Km from my shed, it would be darn time consuming travelling from the front of my shed to the front shed!:D

Have a great day up there Cliff.

Alan...

rrich
27th November 2016, 03:17 PM
That's only four! Where are the other 96? :D

justonething
27th November 2016, 04:02 PM
I use my Tormek to wet grind to an edge and then hone it on the leather wheel and then I'm back at work. It's very quick now. I made a jig so the all chisels and plane iron always protrude from the square edge jig by the same amount. I have 2 universal support bars, one for each wheel. So there is minimum setup. The only things that I do outside of Tormek are to get rid of the burr at the back on a flat 1200 grit stone after grinding and pull the back of the chisel along a chromium oxide charged surface a few times after honing on the leather wheel.

fletty
1st December 2016, 03:42 AM
When it calls for it I'll lap the face of them on my bench grinder.



Your shoes or the chisel :yeah: