Abrasives and edges

[Herman Trivilino]

Great pics and very interesting but what has this got to do with the Tormek as it only has two grits plus the honing wheel?

With the advent of the Japanese Waterstone that's no longer the case.  Plus, just because we've got the Tormek doesn't mean we can't use other sharpening tools.

My take on all this is that the Tormek leather wheel is good for removing the burr.  It will not polish the bevel properly after grinding with the 1000 grit grindstone because the abrasive used in leather wheel honing is of too small a grit.

[Rob]

you mentioned before that the shine derived from a honed tool is coming from the valleys in the scratch pattern rather than the ridges right? (I'm recalling a post you did where you examined it under a microscope I seem to remember)

So that means the grit in the honing compound is being squashed into the valleys by the soft leather substrate?  And that the grit is too fine to abrade off the peaks of the scratch pattern?  Again, just trying to confirm my understanding

[Rob]

Nobody has responded to the question I posted recently:

Can forum members report their honest feedback on results after honing on the leather wheel?  I am genuinely interested to know if any of you are achieving 100% consistently repeatable success when honing on the leather strop.  By that I mean that the tool is sharper after honing than it was straight off the grinder at 1000 grit.

And by sharp I mean Jeff's paper cutting style sharp...you know...really sharp.

I still bang on about this because I'm not getting 100% success, I'm getting some, but its inconsistent and I just know its not poor honing technique because I'm too careful for that to be a variable. I certainly get polished ie shiny steel but its not necessarily sharper than straight off the grinder.

I am really interested to learn (and therefore explore why) what people are experiencing.

[mike40]

My very limited experience is probably not particularly valid Rob, but as I mentioned in an earlier post, I used my one Tormek sharpened and stropped chisel one whole day on soft wood. I did a lot of work with it. At the end of the day the chisel still felt very sharp and it passed the fingernail test. ThenI did the paper test. It didn't cut, just tore the paper. I took it directly to the stropping wheel for about 30-40 seconds and did the paper test again. This time it passed the test, cutting as well as after my original sharpening session. Now a disclaimer; the chisel in question is a very cheap one purchased 17 years ago as part of a set of four for the equivalent of about 5 pounds. The steel might be pretty soft and therefore easier to strop than a better quality chisel.

[Rob]

you see that's fascinating Mike because I'm experiencing that too.  I find I can "wake up" a dull chisel with the strop as long as its not too far gone. And yet once Ive got the burr removed from sharpening, I don't like to mess further or it often seems to get less sharp. (It tears rather than slices paper).

[RobinW]

I'm in the same place as Rob. Although I haven't done any defined tests, I am sure that when I hone the bevel I am sure it is not as sharp as straight off the fine graded wheel. Yes super shiney and very smooth, but........

I don't have enough needing re-sharpened at the moment where I could do something quantitive, but there are some which will need re-sharpening soon, so I will do some with and without honing and see if I can get something definitive.

[Jeff Farris]

General comments from what I'm reading here....

I think en masse you guys are doing a tiny bit of rounding over of the edge. I get that impression from the comments about the tool not being as sharp after honing as before. That's not possible unless you're bringing one angle or the other too steep into the leather, and I'll wager that it's the backside where you're doing it.

Kiss the edge.

The other area to watch to really get the most out of the honing wheel is the step immediately before the honing wheel. The better the surface finish of the final cut off the stone, the easier it is for the honing wheel to deliver a mirror polish quickly. I wholeheartedly disagree with Herman's comment a few posts ago that the honing compound is too fine to polish the bevel properly. If you're not getting a mirror polish in just a few moments on the leather, your stone surface wasn't properly graded to the fine cut. If you're getting "polished grooves"...the step you blundered wasn't on the honing wheel, it was the last step on the grindstone.

This gets back to a reply I wrote to Mike a day or two ago. I think the true key to Tormek success is learning to make the grindstone do what you want it to do with the stone grader.

[Rob]

I will say one thing about that last step on the wheel that I notice. Once you've graded to 1000 and fine tuned at that grit...just like at 220 you can hear and feel when the stone has sort of "worn off" the sharpest of the abrasive particles that were sticking out of the surface.

The stone is probably not really "cutting" as such now, more burnishing, a sort of rubbing I guess.  But I swear that if you do a few more passes when its like this AND with very light finger pressure, its almost like you've gone up another step in grit fineness.  That technique also seems to give a really sharp bevel straight off the wheel. (There is also a lot less burr)  It even looks a bit more polished too though nothing like after stropping.  I guess you're saying take that very fine surface direct to the strop and do it there.  I think next time I will try jigging the tool with the strop.  That should eliminate operator error as regards rounding over (but having to do that faffing really goes against the grain for me personally). It's funny...I have no objection to jigging the tool for the grinder...and yet I'm all "Mr Complaining" when I have to jig it again for the strop!

Perhaps the solution is for me to go into therapy :-)

[Jeff Farris]

Okay, we're really getting into nuance here, but then the devil is in the details.

A dull clogged stone will burnish. A correctly graded stone cuts, but cuts with very fine surface finish. I agree that diminishing pressure on the graded stone is productive.

I'm always surprised when I use a jig when honing. I don't do it as a general rule. In my demonstrating days I wanted it to look easy, and I wanted to teach people how to feel their edge on the wheel. On those occasions when I have used a jig with the honing wheel, I find I get to a mirror finish faster.

That said, my biggest objection to using a jig is that I go back and forth from the back side to the bevel side several times while honing. Maybe as many as 5 or 6. The jig is completely in the way on the back side.

[Herman Trivilino]

What I see with the 40X microscope is not polished valleys or polished grooves.  I'm getting a polished surface with scratches in it.

When I finish grinding at 1000 grit I see the scratches that are left in the surface of the steel.  Honing polishes the flat spots between the scratches giving me the mirror finish.

I will experiment with making sure the grindstone is properly graded to 1000 grit and try honing with a jig.

It's a big step between the 1000 grit stone and the honing compound.

[Ken S]

I believe we are trying to accomplish two distinct sharpening operations with one method.

Jeff has noted that using the leather honing wheel with the tool in the jig seems to polish the bevel more quickly.  I believe this is correct, and probably a very efficient method to accomplish this.  Polishing the bevel involves smoothing away the small scratches left by the stone when properly graded fine.  It also involves eliminating the burr.

With the back, no such scratches should exist.  If the back has been properly flattened and polished, it should be mirror smooth.  Only the small burr left over from the finely graded wheel should need to be removed.  I believe this is most efficiently accomplished on a flat surface.  Whereas a slight rounding on the bevel side may in fact function as a micro bevel, any such rounding in the back of a chisel acts as a sharpening defect.

I believe the simplistic way to make these sharpening issues compatable is to leave the tool in the jig and buff the bevel.  For the back, tape a piece of cereal box cardboard to a flat surface like thick glass or granite.  Squeeze some Tormek compound on the cardboard.  After buffing the bevel, remove the jig from the USB.  Leave the tool in the jig and strop the back on the cardboard.  Go back and forth between the USB and wheel for the bevel and just the tool in the jig for the back.

I have seen using a ceramic stone suggested for this.  This could be done with my idea, but it would involve cleaning the tool for each cycle.  Using the cardboard with compound eliminates this extra step.

Clues for this came from Rob mentioning that he left his roughing gouge in the Tormek jig for fast touch ups.  From Jeff for mentioning the quicker polish when demoing by honing with the tool in the jig and again from. Jeff for suggesting the problem may be slight rollover on the back side.  Using flat cardboard on the back would eliminate this rollover.  Also noted is Leonard Lee mentioning using cardboard in his sharpening book.

This is an interesting discussion.  Let's continue to pursue it.

Ken

[Rob]

well I like that for an idea Ken.  If Jeff's contention that rolling from the back is more probable than the bevel side then your method should eliminate that.  Why couldn't you just do the stropping of the back on an old fashioned oil stone come to think of it (the fine side).  Then as you say rotate back to the leather strop with the bevel still jigged.

I'll try that and your method see of it gets the mad sharp we're all on about.

Or, I guess you could flatten on the side of the wheel?  Ah no...that's 220 grit isn't it....you cant grade that to 1000 can you Jeff?  I think this has come up before..cant remember.

[Jeff Farris]

My problem with working the backside on a flat surface is time. The honing wheel will remove the burr and mirror polish the back (more than it already was) in a few seconds. Doing that on anything flat is going to take longer. You're also right there -- already working on the machine...why set something else up?

If you're rounding over the backside of your tools you don't need another set up, you need to learn how to use your honing wheel.

Sorry if that sounds blunt, but the point of this forum is to teach people how to do things on a Tormek. If there was a serious issue of causing backside problems on the honing wheel, I would be the first to admit it and suggest alternatives. Heck, I don't even work for Tormek any longer. I'm here because I believe in the product.

In 1982 I went to work for Don Peschke at his relatively new magazine, Woodsmith. That's where I learned what sharp is. We used to have competitions to see who could get the best edge the fastest. The art director won consistently, but I was always in the running. Woodsmith stressed (and still does to my knowledge) backside flatness. I believe in it. I embrace it, I practice it, but I will not be convinced that I will destroy my flatness by using the Tormek honing wheel to deburr and polish. If I've shaped the back properly (usually on the side of the wheel, and btw, yes you can grade the side), the honing wheel just doesn't cut enough to alter the shape, only the surface finish.

[mike40]

Interesting discussion and ideas Ken. I think I will try removing the the burr on the back with my 1200 grit diamond plate with a little water. One advantage with the diamond plate is that it is very flat and stays that way. I can't see it ruining the polished edge on the back as it only takes a very light pressure to remove the burr. If that doesn't work I will try the diamond paste on cardboard.

[Ken S]

Good comments, Jeff. Your bluntness will help my sharpness get sharper.

Ken