Square end Chisel

[Hat]

I have the older Tormek it is the green one. Anyway I have tried and tried to sharpen a Japanese Chisel square I was told to get the Jig SE-76 and it will square up my chisels. Which I bought. I can get the chisel sharp but I can't seem to get it square on the end. I did buy the update support bar. How do I check to see if it is square to the wheel. I have some Stanley chisels and they won't square up either. That are not as bad but they still won't square. I know it is me doing something wrong. What is it?

[tonylumps]

I had the same problem. Both thumb screws have to be tightened even or it will cock the chisel to one side. And what I did find out with a new set of chisel's out of the box they were not square to start with. I have a 3" starrett square that I use before, during and after sharpening my 1" to 21/2" chisel. They are the ones I am really concerned about.

[RobinW]

If you look in the Forum section "Hand Tool Woodworking" you will find the following two topics regarding square edge tool SE-76 and the issues some of us have experienced in trying to get square edges, and how we got round them.

a) SE-76 - random thoughts on grinding a square edge - started by KSMike

b) Square Edge Issues with SE-76 - started by RobinW

Trust these help

[tonylumps]

You just can not pop a tool in a jig and go for it .Weather it is a Tormek or a 3000.00 tool sharpener. You have to find out where to begin so you can end up where you want to be.And you need the tools to check the tools. I admit I have learned the hard way.At 70 years old I am still learning, hopefully the easy way.

[Ken S]

Two possible (related) gremlins come to mind:

If the blade projection is very long, any unevenness in finger pressure will be magnified.  When sharpening chisels, I like to keep the blade projection very short.  I generally set the Universal Support Bar distance by using the closer setting on the TT-100 tool.  The exact distance doesn't really matter for this application.  Using a block of wood or eyeballing would work just as well.  The point is to keep the blade projection short.

Since the blade doesn't project far, the effect of uneven pressure is moderated.  This is the exact opposite of setting up to sharpen a jack plane blade where you want long projection to add a radius with pressure manipulation.

The constraint with this method is that the three inch Starrett square won't work unless the blade is removed from the jig.  Removing the blade for frequent inspection is self defeating.  Machinists often modify squares.  That would seem outside the scope of sharpening chisels.  However, a small square could be fashioned by sawing and filing a piece of unhardened metal.  One side could be long enough to check the widest chisel; the other just shy of the distance from the edge to the jig.  The accuracy could easily be checked with the Starrett square. A simpler method would be to use a combination or double square.

If anyone from Tormek in Sweden is reading this, a small square would be a very nice accessory.

Combined with careful checking and practice, a short projection and light touch should minimize the problem.  Adding Mike's idea of truing the front jig surface seems like a fine idea.

The problem of being out of square is not unique to the Tormek.  I once carefully sharpened a wide paring chisel with Arkansas stones to a very keen edge.  It was a fine slightly skewed chisel.

Ken

[Dakotapix]

Is it also possible that a wheel that is not a true 90 degrees from its sides can cause a skewed edge? I solved a lot of these problems when I upgraded my old green 2000 with the latest truing jig and the SE-76. I do, however, check with a small adjustable square while I'm sharpening.

[Rhino]

I want to add that too much pressure bends the universal support arm.  The universal support arm is only supported on one side.  When truing up with the diamond tool, make sure not to rest your hands on the tool rest.  When grinding, apply pressure on the tool, don't apply pressure on the support arm.

I agree with Ken that the blade projection should not be long.  It will just magnify any errors in alignment or any tolerance in the jig.  Basically, the wheel is "true" where the diamond tool meets the stone.  If the stone is slightly misaligned with the tool rest, any misalignment will be magnified the further you are away from the point where the diamond met the stone.  Alignment is never perfect.

From my microscopic work days, basically, all tools start to lose tolerance and wobble the more you extend it - regardless of what the manufacturer says.  The universal support is flexible slightly.  Keep it as low as possible.  Keep the projection as short as possible off the jig.  By keeping all of it short, you have a nice strong system that will resist deflection.

Try to grind at the same projection all the time.  Then, at least, when you make a correction, all your future grinds will be corrected the same way.

For my work, my chisel tolerance is not critical.  I don't worry too much about it.

[Ken S]

Well said, Rhino.

Ken

[Jeff Farris]

Dakotapix is on the right track. Everyone else is, too, BUT, if you haven't trued the grindstone to the Universal Support, all bets are off. That is the first thing to check and get right.