Leather honing wheel out of true

[arnman]

Herman,

Thanks for your idea - I might try mounting to a high speed grinder if I can figure out a way to do it.

Last night I tried to sharpen and hone a chisel, even though I know the honing wheel is not round.  I went through the whole grinding process, then honed by hand.  I ended up with a sharp-feeling chisel that would catch my finger nail with no problem. 

After the honing process, with the grinding stone still spinning, I looked at the grinding stone to admire how round I had gotten it with the truing tool.  I could not believe my eyes, but I was noticing a "bob" in the stone it turned, when comparing the outer edge of the spinning stone to a stationary spot on the wall just beyond the stone!

After just one chisel, how could this be?  I put a 6" rule across the cutting surface of the stone.  Apparently, there was also a crown (hight point in the middle) in the stone!  This would result in a negative camber on the tool - and would never be acceptable for a plane iron.  I was discouraged and packed it up for the night.

Since then, it occurred to me that I must have used a bad technique with the grading stone, and rounded over the outer edges.

I will re-true the stone and try this again. 

I will also try the honing wheel as-is again.  I read some of Jeff Farris' earlier threads.  He mentioned that sometimes the honing wheel has a bump which works itself out "after a few months."  If good results could still be had with a bump, maybe this won't prevent me from getting good results either.

Steve

[Herman Trivilino]

I could not believe my eyes, but I was noticing a "bob" in the stone it turned, when comparing the outer edge of the spinning stone to a stationary spot on the wall just beyond the stone!

By "outer edge" do you mean the (cylindrical) cutting surface? So you see it bobbing up and down?

Or do you mean a side to side wobble?

After just one chisel, how could this be?

Maybe it was there all along and you just noticed it.

Some side to side wobble is tolerable. You can try rotating the grindstone relative to the mounting washer to relieve at least some of it.

If you have bobbing up and down you should also notice it when you're grinding your chisel.

By the way, the cutting action of the grindstone is most aggressive right after a truing. Don't expect it to be like that all the time. Keep a damaged chisel handy for sharpening after each truing. You wouldn't want to sharpen a nice knife with a freshly-trued grindstone.

[arnman]

Herman,

The "bobbing" I was referring to was the outer cutting surface.  I should stress my observation was very minor.  It did cause me to take a closer look, mostly at the wheel crown - which was fairly significant when holding a straightedge across the cutting surface of the stone.  I am convinced that this is due to my poor technique with the grading stone.

I re-trued the wheel and then used great care to use even pressure when grading.  I did not move the grading stone side-to-side as shown in the instruction diagram.  Because I am still new at this, I am not entirely sure how to know when enough grading is enough.

I sharpened two chisels and honed using the wheel.  I don't know if I was being overly careful not to round over the edge, but I had a hard time chasing off the wire edge.  Even though a small amount of the wire edge still remains, I can cut paper with both chisels.  But not as easily as Steve Farris makes it look.  Maybe thinner paper would help.

Any comments for chasing off that last bit of wire edge?  Perhaps it is steel quality.  One of the chisels is a cheapie.  The other is a Marples made in Sheffield.

One comment I have is that I did not like the look of the dried diamond paste dust floating up into the air as I was honing.  Micron-sized diamonds can't be doing any favors for the lungs.

Steve

[Herman Trivilino]

I am convinced that this is due to my poor technique with the grading stone.

I really doubt you crowned the surface with the stone grader.

Any comments for chasing off that last bit of wire edge?

Keep alternating between the front and the back as you hone. Run the edge through the end grain of a piece of scrap wood.

[arnman]

Herman,

It is interesting that you doubt I crowned the stone with the grading stone.  It seems to me that there could be no other explanation.  It was not due to my grinding process (only 2 chisels).  Also, after truing and using my more careful grading procedure, and regrinding the chisels using the same procedure, I did not have any crown troubles.

By poor technique with the grading stone, I think that I inadvertently exterted higher pressure on the outside of the grinding stone when moving the grading stone back and forth, thereby rounding over the outside edges of the grinding stone.

I am working my way through the epic kennyk thread (about 3 pages in so far), and he seems to be convinced that the same thing had happened to him.

I am hoping for a happy ending to that thread.  I don't want to look ahead.  I am hoping to pick up a few lessons along the way.

Steve

[Herman Trivilino]

I can see how you'd round off the corners of the grindstone with the stone grader, but not a crown across the entire surface. Not in the sort time you had, especially. I would think it more likely that the crown was there after you trued the grindstone the first time, and you just didn't notice it until after you'd sharpened those first two chisels.

Anyway, it sounds like you've got it all sorted now.

I think Kennyk's problem was different. As I recall he reported that the grindstone was true, and then swapping machines solved the problem.