an interesting comment on using or not using the Tormek wheel to flatten blades

[Ken S]

I found this in our archives, and thought it might be interesting and relevant for those who want to flatten their backs:


Hand Tool Woodworking / Re:Not just for TORMEK -- LET'S TALK HANDTOOLS!
« on: December 23, 2003, 10:16:57 pm »
Just to clarify my approach to sharpening.  I use the Tormek for grinding only, despite having had an excellent half morning's session with Torgny Yansson!

My sharpening is done on 800 and 8000grit waterstones.


Many people who come on my courses have done irrepairable damage to the flat side/back of their blades before arrival.  Please beware of rounding the flat side on hollow waterstones, or even the scary sharp method.
David Charlesworth.

[Rob]

I found this in our archives, and thought it might be interesting and relevant for those who want to flatten their backs:


Hand Tool Woodworking / Re:Not just for TORMEK -- LET'S TALK HANDTOOLS!
« on: December 23, 2003, 10:16:57 pm »
Just to clarify my approach to sharpening.  I use the Tormek for grinding only, despite having had an excellent half morning's session with Torgny Yansson!

My sharpening is done on 800 and 8000grit waterstones.


Many people who come on my courses have done irrepairable damage to the flat side/back of their blades before arrival.  Please beware of rounding the flat side on hollow waterstones, or even the scary sharp method.
David Charlesworth.

I'm confused....who is rounding the "backs" of their chisels and plane irons?  The advice is always the same (including in the Tormek manual) which is to get the best edge the back needs to be lapped perfectly flat. And at that.....only right by the tip near the edge.  It sounds like his students have been attempting to lap their chisel backs on the wheel itself rather than the flat side?

David's usual hobby horse against hollow water stones is the concave curvature left on the bevel.  He says that undermines the edge so it doesn't hold as long as a manual ground one on a flat stone

The truth is he's almost certainly correct.  But for the vast majority of normal woodworking his level of perfectionism is overkill. His specialism is absolutely perfect joints done by hand. He's not a big fan of machine tools...it's very very refined stuff he does...and he's famous for it.

The time trade off using manual sharpening methods versus the tormek doesn't work for me.  Give me the Tormek every time

Leonard lee says best of both worlds is grind the bevel on the wheel but hone the secondary bevel (1 degree only) manually

I say, get your Tormek out and do the lot. I can take plane shavings with a 70 year old Stanley bailey smoother to a few thou.....frankly that's enough.

Now if you're running a training business and selling DVD's that market your "super special sharpening technique" then that's different.......or am I just a tad cynical?

I sharpened manually with a honing guide for years, after I got the Tormek I've never looked back. I can honestly say, I can't tell the difference.

I've also always lapped the backs ( just the very tip) on the side of the stone and know they're dead flat by the eradication of the factory grind scratch pattern all across the chisel

[Herman Trivilino]

Now if you're running a training business and selling DVD's that market your "super special sharpening technique" then that's different.......or am I just a tad cynical?

Well, Rob, perhaps a bit more than a tad ... but based on my experience you're exactly right.  Very nice post.

Before Tormek my experience with chisels was to use them for pry bars after the inevitable dulling they'd get when I hit a nail.

I never knew what a sharp chisel was, and despite growing up in what was very much a do-it-yourself family environment, no one had ever taught me.

I'd love to work on a timber frame project some time and see how well I could tune those mortise and tenon joints.

[Elden]

I had (still have)a Foley Belsaw 1055 Sharp All that a sharp chisel edge could be coaxed out of. Working on the back side of a chisel, never heard of it before the Tormek.

[Herman Trivilino]

You don't really work on the flat side of a chisel.  Flattening it is a one-time operation that's performed to remove flaws in the manufacturing process.

[Rob]

Correct. The only time you might need to relap is if you sharpen the bevel so many times the length of the chisel reduces beyond your original lapping

[Elden]

I realize that it is for one time, but I had never heard of making sure it was flat and polished. For a framer that is like using the best China for your coon dog!

[Herman Trivilino]

Correct. The only time you might need to relap is if you sharpen the bevel so many times the length of the chisel reduces beyond your original lapping

While I've got it on the grindstone I just flatten it all the way to the shaft.  My largest chisel on a one-incher, so ...

[Herman Trivilino]

I realize that it is for one time, but I had never heard of making sure it was flat and polished. For a framer that is like using the best China for your coon dog!

Well, I don't polish the back, I just grind it smooth.  Some new chisels have ridges in the back so you're really wasting your time trying to sharpen, let alone polish the bevel, on a chisel like that.  Flattening the back is pretty much a necessity, even for a framer, or is it a first fixer? 

[Ken S]

I would respectfully disagree.  Too many people I respect teach polishing the back.

Ron Hock's book is handy:  "Proper honing of a chisel relies on properly flattening the back.  As with plane irons, a flat, polished back is essential to a sharp edge." (p 125)

Ernie Conover always teaches that a sharp edge depends on both planes, the bevel and the back.  He takes both to 8000 grit.

My forty year old Stanley butt chisels have done the heavy work for me.  They frequently have received nicks.  I can always see myself looking at the backs.  Is this overkill or just good sharpening technique?  (Actually the mirror backs go back to when they were my only chisels and did dovetails as well as rough work.  I would still polish rough chisel backs.)

Ken

[Rob]

Guys....there are no absolutes here?  You sharpen according to the job you need your tools to perform right?

If you are a first fix carpenter (framer) on a construction site putting in door linings etc, there is no way in heaven you're going to lap the back of your chisels.  You're working to rough tolerances...your goal is primarily speed

I've built two houses and renovated two including one 400 year old cottage with an originally thatched roof.  Speed is your primary concern.

Cabinet makers....of course....absolutely.  Second fix carpenters...probably if they really care.

You invest the amount of effort required to produce the quality the job requires.

This isn't black or white.  There isn't a right way and a wrong way....there are just varying degrees of effort that produce varying degrees of accuracy.

[Ken S]

Good point, Rob.  I've never lived in a high production framing environment like Herman has.  One of the things I value in this forum is being able to share our different backgrounds. 

Ken

[Elden]

Guys....there are no absolutes here?  You sharpen according to the job you need your tools to perform right?

This isn't black or white.  There isn't a right way and a wrong way....there are just varying degrees of effort that produce varying degrees of accuracy.

Rob, good point.

Obviously even though my carpentry experience was short lived (I moved on to large equipment operation), the people I worked with didn't put any emphasizes on having a precision wood chisel. It was mostly used for finishing the cut of the bottom plate board for a doorway in a stud wall (that was before the reciprocating saw became standard) . We sure didn't think about a chisel being used without using a hammer on it. I cringed if had to cut into concrete, but it was part of the job if we forgot to cut part way through the plate before the wall was anchored.

Did I learn differently eventually? Yes, and I'm still learning!
Would I sharpen a chisel for someone now without making sure the back was done properly? No, probably not unless that person requested that it was left alone.

I definitely like a sharp chisel that can be pushed through the wood without using a hammer to strike it. It kind of like a good tasty hot chile pepper. I sure didn't know what I was missing before learning to like them! As time goes on, I enjoy them being hotter than I used to. So with the sharpening!

[Herman Trivilino]

Ken, I had never thought of polishing the back of a chisel.  But it does make sense.  Why polish only one side?

[Rob]

Haha. I like your chilli analogy Elden