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Guys, let's keep it civil.  I've deleted a few posts, hopefully without actually removing anyone's opinion, but getting rid of some of the unnecessary bickering. I don't want to delete this thread, as it has some good information in it.

I haven't sharpened a lot of thousand dollar knives, I will admit. I have sharpened thousands of hundred dollar knives, and with every conceivable method available to me, I would continue to choose the Tormek.

tb444, sounds like you need to become better acquainted with your stone grader or get an SJ-250 Japanese waterstone. If you (or those you've observed) are removing material at that fast a pace, the stone is not graded properly. If you give the SJ-250 a try, I think you'll find the speed well worthwhile compared to water splashed bench stones, whether jigged or freehand.

I have the sj250 lol, i do feel i gave the tormek a good run, but this is where obsession with the geting the best out of my knives comes out, and i will admit to it

The speed of cut with the 4k stone is IMO rapid and this is no bad thing, a slow cutting stone is frustrating and is why i stopped using oilstones a long time ago. When i am block planing endgrain or abrasive woods i will mark the jig position on the blade with a Sharpie and then leave the 4k set up for really quick and frequent touch ups. With a 25 degree primary the 4k will keep going with a 30 degree secondary for quite a while before i need to redo the primary on the coarser stone. If it cut slower i'd just use the strop or a benchstone progression.

This is no criticism of the tormek, i'm a big fan and will recommend it to people looking to be able to put fast repeatable sharp edges on knives and tools. But i see a knife as being affected by more than just the edge bevel but the geometry behind the edge as well, and being able to maintain or modify this is something that i dont feel able to do on the wheel.

Saying all this i was at a camp out last weekend and must have sharpened about 30 knives for people that were all blunt to start off with and being able to reset the edges quickly on the tormek would have been a big timesaver. I would have then been able to spend more time on the geometry instead of grinding away trying to get an edge back first.

i find a diamond bench stone useful for cleaning the surface of the japanese 4k stone. Little and often, i also relieve the corners of the edge of the stone lightly. If it's a long way out of true i'd use the diamond truing tool but take it very slowly and lightly

Any steps up from there and i'd worry putting them to the tormek, (no disrepect to the tormek, just greater respect to the knife).

Are you saying you would only use traditional water stones on more expensive knives? What is it that the Tormek would or wouldn't do to the knives?

When sharpening higher end knives, as well as maintaining the edge geometry, there is also the overall blade geometry to maintain by thinning behind the edge. doing this on a tormek would be precarious on a tormek due to the very low angles involved and the desire to maintain a convex geometry to the blade.

The speed that the tormek will abrade a very thin edge makes any errors quickly magnified, and also will remove steel at a rate more suited to putting a fresh edge on than regular touch ups. If you have a knife that cost a lot of money due to the steel, heat treat, grind geometry, you'll want to keep it sharp through regular maintenance, without reducing it's lifespan through excessive wear.

The ability to match the edge geometry the whole length of the blade, whilst being constrained by a jig is likely to result in uneven wear, resulting in subtle, but if compounded noticable changes in the knife profile. i would agree to an extent that practice will reduce this, but i have seen a lot of funky tips and flattened transitions from tormek grinding.

you'll end up with a subtle concave grind that doesn't do much to contribute to edge stability at angles of around 10 degree per side, which is part of the advantage of higher grade knives because they will support extreme geometries.

There is also the concept of asymetric grinds on edges, that would necessitate resetting the knife in the tormek, adding to the set up time. The speed of freehanding with splash and go benchstones also rivals that of the tormek if you only have 1 or 2 to do, as by the time i've set it up, saturated the stone and jigged the blade i could have pretty much finished a knife. but that is an aside.

When Herman commented that a well done Tormek edge will be better than a hand ground edge i would strongly dispute this. I've spen a lot of time with the tormek trying to get similar edges to those i can get freehand, and done some quite exhaustive cutting tests. I do want the best functioning edge on my knives, if i've spent $1000 for a knife i want to get that every bit of performance out of it, and freehand edges win every time. The difference is less apparent at the lower end of cutlery, but once you get into beter blade steels with top notch heat treats it does make a difference.


To the poster who commented on Global knives not being sharpened by a knife steel that's due to the hardness of the steel. Your global knife will be at 58 Rockwell C, which will be very close to that of your steel and so there is no noticable abrasion if it is a cut steel. If you have a smooth steel this works by realigning a folded edge, but the global edge wont tend to fold at the standard geometries (and will quickly fracture if you attempt to realign it with a steel). So is mostly a waste of time. That is why Global sell ceramic and diamond steels, as these are abrasive and act to remove steel from the edge.

Whilst global knives are better than a lot of the junk out there, the steel in them is still very run of the mill and soft in comparison to higher end knives.

The OP's knife is a factory ground, and without any offense intended, isn't a top class knife. go into any kitchen knife shop and look at the bevels on the knives. if you find one with a perfectly centred evenly ground edge you'll be lucky.
From the sound of the post this is the first time he's sharpened it and the tormek bevels aren't matching the factory bevel.

The jig being at fault is the last thing i would presume. My order of probability would be wonky factory grind, operator error, then jig.

Also note that not all knives are ground symmetrically, or designed to be. Following the factory bevels on each side is a good start. putting a 50/50 edge on a 70/30 ground knife can lead to steering issues, but these types of edges tend to appear on japanese double bevel knives

A bit late, but +1 to Forschners. They are one of the best bang for buck knives around.
If you want to step up from them JCK Carbonexts are great knives as well but being semi stainless take a little extra care.
Any steps up from there and i'd worry putting them to the tormek, (no disrepect to the tormek, just greater respect to the knife).
Nicest knives i've used are made by some of the custom makers i've been fortunate to have experience with (Devin Thomas and Will Catcheside are two that spring to mind instantly)

My advice would be magic marker and slowly approach the edge from the back of the bevel until you hit the edge

i'd change the angle of attack to be much more skewed so that instead of approaching at 90 degrees you are much closer to 30, that way you won't hollow out the bevel.
I'd paint the whole bevel in magic marker too....

You raise a good point, it's definitely worth understanding the value of what you are sharpening before agreeing to work on it.
Although, most tools are difficult to damage through sharpening on the tormek, the advantage of a jigged system.

It depends on the steel - different alloying elements will affect the grain size, carbide type and distribution, and also on the heat treat of the steel as to whether it will stay sharp. Any steel should be able to take a sharp edge-who's cut them selves on a baked bean can?
The burr removal seems to be the problem you are having which again depends on the alloying elements and the heat treat. The amount of burr flex you are experienceing suggests the steel is quite soft so i wouldn't expect this chisel to ever take a good edge but it should get sharp. One method of burr removal you could try is to slice the edge through the end grain of a pice of wood-as though slicing with a knife. This should pull the burr of, and you can then refine the edge on the leather wheel.

The toothiness you mention, may be due to the steel having very large carbides, which as you sharpen are getting ripped out, leaving behind the soft matrix which won't support a sharp edge.

Thin filet knives can cause difficulties due to the narrow blade and the flex towards the tip, if you don't want to go freehand you could make up a wooden jig by putting a rabbet along the edge of the same depth as the knife thickness, but slightly narrower so that the edge protrudes, and then embedding some strong rare earth magnets to hold the blade securely from the one side only. This way you have jig that will hold the knife with nothing below the blade to hit the stone.
Ill take some pics if you cant decipher what i mean

For knife sharpening you should keep the stone graded fine, unless you doing reprofiling chip fixing. I have the sj 250 and don't think it would benefit your kitchen knives much unless you have very high end knives.
If you do have knives with high quality steel that would benifit from going to 4000g then you may find that you get better results freehanding on bench stones. No disrespect to the Tormek, on standard kitchen knives, the fine graded wheel followed by the leather wheel does a quick, accurate and good job.
The time where i do like the sj 250 is with my hand plane blades and chisels, being A2 steel these are also much better at edge taking that the standard 440 stainless seen in kitchen knives.

Recurves are very hard to do on the tormek i would suggest going freehand.
Buy some different sized wooden dowel and some automotive wet and dry paper up to around 1200g. The radius of the dowel should conform to the curve of the blade, and with abrasive paper glued around it can be used to sharpen the edge. Work through the sand paper grits until you have it sharp, then add some of the tormek paste to a clean piece of dowel and use to polish the edge.
Use magic marker to help you match the angle and go slow. If you are worried about scratching the face of the blade, wrapping all but the edge in decorators tape can save a lot of annoyance

In all honestly i wouldn't touch a single bevel japanese knife on a tormek unless it was a very cheap knife that i didn't care about. They have a complex geometry with the Uraoshi (slightly hollow flat) on the back side needing careful maintenance with gentle strokes on a very flat and very fine stone with pressure only on top of the edge. The main bevel sould be lightly convexed (hamaguriba profile) to assist with food release. Further the Shinogi line needs to be kept crisp and parallel to the edge.

Whilst i fully respect Jeff and will say that the Tormek can be used to maintain double bevel knives admirably, single bevel japanese knives are entirely different and it would be very easy to ruin the geometry very quickly.

Lol, i'm just usually willing to pay less than others as i don't actually need it.... though it is frustrating when the winning bid is $1 more than my max bid...The most i'll pay is what i could sell the two 1200s for

The more i use the 4000 stone though the more i like it,  no longer take any of my woodwork tools to bench waterstones which are now used only for my good kitchen knives