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Yes, there is actually nothing new under the sun 

As one might expect, there is very little new in electronics, at least in analog circuitry. (...) Sometimes the innovators try to make their transfer of known electronics methodology from one discipline to this one seem revolutionary. The revolution is not actually the technology, but rather its revelation to the rest of the world.

- Kevin O´Connor: The Ultimate Tone Vol 4, Power Press Publishing, Thunder Bay, CN, 2006, p. 4-15f 

Great that you find that useful. That rewards my effort.

(...) axes have been used as a sledge, (with the backside, not the edgeside)

That is quite common, because it is intuitive. I have done it until I recently read (surely in one of the sharpening books) that the heavy butt end is solely there to balance the axe. It should never be used as a sledge hammer, although it looks like.

But who of us laymen seeks training for the feed and care of axes?

Logic dictates that you use clamps with sufficient depth so that you can grip ahead of the mutilated area.
On the other hand, don´t choose them too large; I think an integral part is the spine of the clamp (if that is the appropriate term for it...) resting firmly against the axe´s butt.

For the axe shown, the proposed radius´s center does not quite meet the mounting point. But like sharpening a knife, you control those things with lifting the handle and/or pivoting. So since the axe is a rather coarse instrument, unlike a delicate knife blade,  you have plenty of passes to see where you get.

And as some of the renowned sharpening masters said (about chisels): Don´t worry about razor sharp. The blade ist only razor sharp until the moment it meets wood...

Hi Nico,

you finally got me triggered and I posted the information about the jig I have made for sharpening axes. It is to be expected, that this works for your problem too.
D.I.Y. Axe and cleaver sharpening jig

Have fun.

[John Juranitch]

This is a description of a jig I made for sharpening axes. Nothing speaks against using it for cleavers or other blunt instruments too, but I have not tried it. I hope you will.

If there were a subforum for axes, then I would put it there, but there is none.
Using it for cleavers however justifies its relationship to knives.

Tormek´s jigs for knives clamp the knives on the spine, hopefully symmetrical around the center to achieve symmetric bevels. Using the available knife jigs, a given knife in the jig gives a projection distance of some 10-15cm, and that´s what the whole system is set up for.

With a chosen grinding angle, this results in a certain T-USB value. All available calculators spit out the corresponding value. So far so good.

Unfortunately there is no jig commercially available that clamps an axe in a comparable way.
There are many ways an axe could look like on its butt, many shape it could take on, and there could be huge variations in thickness. A jig like the knife jig that grasps from the back would most certainly fail.

The projection would become enormous, and T-USB with it. The attempt to use their huge support bar is a palliative measure and does not necessarily touch the problem. The axe jig clamps, but does not help much otherwise.

So I thought, what clamp is adjustable? A screw clamp. It even has a pressure plate that can adapt its angle to the surface with its ball-bearing like holder and thus always stays put.

Unfortunately the other side of such a clamp is fixed. So I bought two of them, and out with the angle grinder, and I mounted the two adjustable halves facing each other with a common spine like shown in the picture below.

For the axe shown, I clamped the jig approximately at the center of the circle the cutting edge describes, or slightly behind that (see later). This lets you pivot around that point. I used the known techniques of lifting and pivoting.

If you take care, the axis of the two screws (resp. the rod) is perpendicular to the axe´s surface, which will guarantee symmetric grind. The two screws function as a pivot point, and the axe becomes the jig. The double clamp grips perfectly, particularly if you have the spine flush against the axe´s butt.

This contraption has several similarities to a knife clamped in a knife jig:

• short projection
• symmetric clamping
• all calculators work

I used the usual calculator, but with a slight change. The calculators work with the center of the jig plane, and they half a given diameter automatically. So haul out your calipers, measure the axe´s width at the clamping point (in other words: the distance of the pressure plates) and enter that value in the position where the "jig diameter" value goes.

When grinding the traditional way (with the stone rotating towards you), you have a certain downwards tilt, just as you would with a knife. Now with the c-clamp jig (I call it the Bessey jig) the USB´s horizontal rod rests against the clamp´s screw (see picture below). The USB bar may initially rest against the pressure plate, but soon before long it will slip over the pressure plate´s rounded edge and find its final destination at the screw. So take care that you always rest against the screw and not the pressure plate when you are changing sides.

Acute readers will notice that this changes the angle, but I found that the angles come out right (gauged with the notches on the angle master) when you measure the axe´s width inclusive the pressure plates at their top. Because that´s the surface the USB finally rests upon.

I made two axes so far. According to John Juranitch´s advise, I thinned down the region behind the cutting edge somewhat. I also polished this relief with a JIS1000 stone, which is more of a cosmetic thing probably. I did not polish the cutting edge. As you see, it holds up nicely after a fair rake of hardwood at a 40 deg inclusive angle.

This jig costs very little and does not require any additional expensive accessories or any contorted postures by eliminating large projection distances.

For the axe shown, the projection distance was 148 mm. At a 20 dps angle the resulting T-USB value was 96 mm. This is fairly at the limits of what the USB can be pulled out (I can only speak for a T‑3) but would come down if I had chosen clamps with a larger depth. The clamps´ depth is 50-60 mm. Next time I get a pair of larger ones. Note the axe it not rusty as it may appear, this is painted with linseed oil, as is good practise.

I can see that this works on cleavers too. The length it grips "forward" just depends on the depth of the clamp you choose. For a cleaver, the depth of the clamps used would probably be perfect.

And don´t forget to reset the jig diameter parameter after use.

(please excuse the less than stellar photographic skills. This is not an art contest.)

Welcome Per.

This is a variation of a standard conical grind with a split point.
I have done it on the Tormek, look up the thread I started recently "Musings..."

You cannot do a sharp corner like that, but you don´t need to. What counts is the cutting lip you introduce at the web.

You can do it, but you may find out that it does not pay.
Again, I have written all the pro´s and con´s related to this subject.
I did not go into depth on the fine details on how I modified the DBS-22 because there is no interest.
And maybe no need too.

Have fun,

-Helmut

Is there any reason for the secondary bevel to be there on drill bits from 3 - 6 mm? what good does it do? i know its suppost to keep it from wobling about, and to make you drill without that much preassure. but besides that should it not cut about the same?

I am not sure what exactly your question is.

the more you grind in the secondary facet the more you remove from the cutting edge near the center of the drill. witch i think again makes the center cut alot worse than it needs to.

I think with "the cutting edge near the center" you mix up the chisel, which is a result of the web with something that cuts. It does not. It pushes metal away. The technical term is extrusion.

the cutting bevels wont even touch the material one is trying to drill.

On a drill with conventional conical grind (most of the factory grinds for jobber drill bits) the center never grinds. You have to push it into the parent metal a fair bit until the facets are catching. Close to the center their effect is limited for several reasons. The 4-facet grind is slighly better, but does not eliminate that flaw.

Drillbit two:
Here is one that didnt cut. i did not bother to cut the seccodary bevel on this one just as an experiment

This obviously had some web thinning measures employed on the previous grind. It should cut despite the absence of a secondary relief, but run hot eventually.


Bit #3 suffers from what RichColvin explains.
Bit #1 (second picture-high spot):

Excessive lip clearance is extensively practiced througout the U.S. (...) Such excessive clearance is due to the tendency to incorrectly view the drill(...). In viewing that drill, most readers would insist that the
drill has little or no lip clearance.

This is a quote from Mazoff´s brilliant article "drill point geometry".

looking at a drill this way you mix up two different angles.
For my taste, Mazoff did not make it entirely clear as how to look at the drill correctly. I think what he is driving at is to look along the cutting edge as if you would aim over notch and bead sight on a gun (English speaking guys please correct me if this is not the right term).

However, this way you see immediately, if the heel is lower or not.

it appears that your primary bevels may extend too far across the cutting face. (...) Notice the primary bevel is very small.

I don´t see anything wrong with that grind. It is perfectly symmetrical.

If your primary bevel is too,large, that would put extra drag on the drill bit.

Mazoff says that a single (primary) bevel works but produces congestion on the heel. Therefore the necessity of a secondary bevel. Indeed small drills are ground that way exclusively.
Such a bevel has more "meat" behind the cutting edge and is thus stronger.

On the contrary, too small of a cutting edge (i.e. to much relief) would weaken the edge.

On second thought, the problem @Lokepus encounters may be no real one at all:

If he is used to drilling (with larger drills) that have a split point, than you will feel the 4F grind does not cut at the center. The truth is, it does not (well). It has a point only slightly less blunt than the conventional conical grind. The fact that the drills work with a pilot hole is indicative for that.

My brother in law, when he bought the jig, sharpened some drills for me. It was the first drills he did and they refused to cut as well, although they looked alright.

Later he gave me the jig and everything worked for me.
He must have done something wrong, I don´t recall what he made differently.

The only explanation is that there is little or no relief angle on the primary cutting edge.
Note that due to the geometry of the pins on the pin vise there may be some intermediate sizes (around 10mm) that won´t grip symmetrically. It has been explained here and a simple solution has been presented.

Plenty people have terribly cheap kitchen knives.
Very often I get some in my hands that must be ultra cheap warehouse knifes. I don´t have a picture of one of them, but they are immediately recognizable by their huge relief bevel. I suppose this is meant to give the illusion of a much higher quality Japanese style knife.

This relief bevel is hollow, maybe not as pronounced as a 200-250mm wheel would give, but still clearly hollow.

Those don´t have a bolster, but end up towards the handle with a ca. 1cm portion that is blunt.

Don´t believe that you cannot get them to a useful sharpness - you can.
Unfortunately the first time you re-sharpen them the cutting edge gets inevitably hollow near this blunt portion and you have to think about a solution for that.

So those are sharpened on the circumference of some wheel and thus hollow.
I tried this procedure on some of my knifes but the sharpening angles are so low that you very quickly run into the jig´s holding brackets.

Grinding free-hand is a desaster, because you cannot hold still enough to get a nice bevel line. At least I cannot, somebody may have mastered this.

I have seen a guy (was it schleifjunkie?) who has made a special jig for this using magnets, but I abandoned the notion in favour of face-grinding (on the side of the wheel). This works very well for me basically (despite what our quasi-standard "Wootz" encountered), but opens up another pandora´s box. I have written about that galore on my recent threads.

I still adhere to that, because on some point, particularly after repeated re-sharpening, you have to thin the knife, until further perspectives appear.

All Right let's change the question in: Who successfully thinning kitchen knives on the Tormek ?

I am. Look up my recent threads.

I once had put more and more oil onto my leather wheel in a misunderstanding of the purpose. To get rid of it again, I used some kitchen paper soaked in polypropylene alcohol and it looked like new again.

I use the same angle for the leather as for sharpening, and a degree more for the felt. My knives' sharpness improved a lot, and I maintain that with a ceramic rod. God knows if they suffered from burnishing.

Hmm. The apex is basically thin as paper. This makes sense.

I have bought an aftermarket F360 (JIS600) SiC stone. I trued it with the diamond no problem, but trying to put the dressing stone onto it resulted in a desaster. The dressing stone was grooved immediately, being of the same nature (the wiser gives way...)

This process I saw named here in this context with the term "glazing", and it sure looks glassy, but I do not know what it means technically in conjunction with a grinding stone.

I have a similar wheel on the (fast) bench grinder (green SiC) which I can only true with a tetra-boron grader stick.

The prior wheel btw is medium hard bond (grade "J") and reacts to pressure, so you can adjust how much it "grips". The SB wheel appears to have that feeling too. Maybe this is a peculiarity of the abrasive in conjunction with fairly weak bonding. That said, the SB is much coarser too.

The re-seller of those (he has them custom made from a huge manufacturer of abrasives in Germany) is a professional sharpener and he had them made because of the very dilemma you outlined above, namely having only coarse grits and very fine grits available and nothing inbetween.

Said sharpener told me that he never uses the grader, because it does not really change the grit (how could it?) but shave off the peaks. The inherent danger is said to be two-fold:

• the wheel can become untrued by heavy grading
• spots can brake free that release fresh sharp material thus making the perceived roughness uneven across the circumference

The #800 Matsunaga stone you mention has been tested by Wootz (linked to by my reference further above) and was found useful only for carbon steel.
It does seemingly little on soft steels. Just to keep in mind.

I was intrigued to get a similar stone in white alumina from the same source (and they are reasonable...)
but the burnishing bit you mention irritates me. I do not know technically what this means.
All I know is every mason I know has one of those (albeit on a fast bench grinder) and every manufacturer claimes "a cooler grind", but I have never read a first-hand explanation for that, particularly in context with wet grinding.

If what you say (that burnishing weakens the steel) is applicable here, than this is an argument that has to be taken serious.

That´s what I ended up with a really delicate chopping knife.
There is a huge downside to this method: the face of the stone will deteriorate, and there is no elegant way to rectify it.

Theoretically you could use the diamond, but there is no support for the jig.
I tried a makeshift support using a XB-100, but there was always something in the way that hindered.

Wootz has a video where he tried that trick on a single bevel knife and he landed with the same conclusion.

For my needs I managed to rectify this problem, but the result is nowhere near as perfect as the guided diamond.

The grey aluminuium oxide wheels have less friable grains and thus wear less but create more heat and friction.

Is this relevant in a slow running wet grinder? I know this to be the reason for all masons, who sharpen their chisels on a fast running bench grinder, to choose a white alumina stone...

I also noticed, that upon starting a grinding pass (such as after flipping sides) it takes a second or so to align the knife optimal to the circumference.
More often than not you are hitting a corner before the blade "pulls in". By this time, you have overground that spot.

One could insert a foot operated switch for that, but then the blade runs dry for a moment.

Has anybody tried such a thing before?