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Small update. My jig is a SE-76, obviously a predecessor. The dimensions are very slightly different.

Calcapp just makes the measurement easier, the "30.1mm" puts it to the back of the USB.

I found this number on the SE-76 to be 29.4mm, so if I interpolate the values it comes out practically the same.
This is besides the fact that this all is not rocket science, to quote myself.

Note that I updated the jig dimension measurements above after finding a more exact method.

A note for Ken:
I was not in vain that I invested the work to describe the planes and what to look for.
The "bessey" method I described somewhere here for sharpening an axe uses exactly the same principles. You cannot use any of the angle jigs to set up the grinding angle on an axe that has curved surfaces all over it.

Thats great. We just described an alternative way that lets people do some number crunching for virtually any jig to come.

Cheers! ;-)

-Helmut

Ken,

it is not strictly a Stanley, which is why I said "akin". Funnily, most people here used to be able to relate to a "stanley planer". It´s actually a now pretty old "Witte Plano" planer.
It has "HSS" stamped on the blade. They were also commonly referred to as "Resopal planers".

I agree that it is not strictly necessary to use a program for simple things like that. That said, devices like the TTS-100 or so may not work too well on surfaces like leather or felt for honing purposes. If we transfer Vadim's knowledge onto chisels and planer blades then honing angles are critical with respect to the grinding angle. The grinding angle by itself is deemed less critical.

I have heared of professionals that do everything by hand and produce razor sharp edges, but those sources seldomly mention the years and years of practise. A "method" that is repeatable and executable by a novice with only a little practise will lead to acceptable results without dedicating a lifetime to the subject.

Curtis, program (parts) like the one you did for the square edge jig are useful, but bear a trap.
The jig may change and all assumptions about its dimensions are up the swanee, or somebody else may have a knock-off that is slightly different.

So providing the basic idea behind it let's people adapt things to their needs. As a famous ancestor of ours said analogously: "I rather teach people to catch fish than providing food for them" ;-)

May I suggest that you add the information to your program how you measure the projection. It is not obvious.

[my values]

I looked at this closely again. Ties my head in knots.

my values (plugged into Perra's program)
I measured from the cutting edge to the rear of the jig: 70mm. I determined USB to rear offset = 5.5mm, give 6. Projection thus 64mm. 5.3 mm. Projection thus 64.7 mm.

center plane displacement = 24.5mm (said to be 25) 25 mm, "jig diameter" thus 49mm 50 mm(just necessary for normal "knife" program)

wheel size = 198mm, sharpening angle 27.5dps yields T-USB = 25.7dps 25.90 dps

calcapp SE-77 values:

your projection value entered is from cutting edge to front of jig, thus 70 minus 35mm = 35
yields T-USB = 26.4 dps

So both achieve virtually the same result, which is relieving.
Those calculations rely heavily on the correct measurement of the displacements. I only had a vernier to determine them and a bit of eye-balling.

It is further relieving since I used the above described "universal" method with my "bessey" axe-jig, which worked well too.

Projection distance is measured from the front of the jig to the edge of the chisel

This will lead to the same result. You will have to add a  constant offset onto the measured values if you use the stock calculator's formulae.

Maybe this is a better idea, because it uses the known method of measuring from the cutting edge to a stop with a ruler.

I never payed attention to this part of the forum so I was not aware of all that. Anyways, the pudding seems eaten and proven.

I never used TormekCalc because it does not run with alternative spreadsheet programs.
I am glad it worked out for Perra's program (Angle Calculator Lite). I like to keep things as complicated as necessary and as simple as possible.

The wheel is that diameter.

Thank you for the link.
I looked at JVH's drawings and the drawings suggests that he determines the offset in the projection plane by referencing the center of the USB, while Rich's drawing clearly references a point on the rear of the USB, which is where the "stop screw plane", as I called it meets the USB. The difference will be 6 mm. Dutchman's formulae (which I believe are the basis of all those calculators) too seem to reference the center of the USB.

I looked up Perra's spreadsheet formulae and saw that parameter "JG", which is taken for the calculation of the triangle, deducts USB/2 = 6mm from the projection value. So both are in a way correct.

I cross-checked with your online calculator, and the results are sufficiently different. What reference point did you choose for calculating the value of projection, based on the cutting-edge-to-jig-front measurement? Center of USB or rear? USB/2 is going to be deducted automatically.

 Can somebody chime in and clear this up?

[line through the center of the spine]

I have recently sharpened the blade of a metal hand planer, which is a look-a-like of a Stanley single iron bench plane SB3 (just to make clear what I talk about). The blades are hardened (HSS), so the standard SG stone will take hours. I used a F120 corundum stone for the coarse work and a SiC stone to make it finer.

Since chisels and similar blades have a flat upper surface, the WM-200 angle tool works fine for that. The recommended grinding angles for those blades are between 20-30 dps (although there is only one side to be sharpened). The blade itself is angled at about 45° from the working surface, which leaves several degrees of relief behind the cutting edge. In my case the bevel is down.

Spoiled by sharpening by numbers, I looked if setting the angle by T-USB was feasible, which would allow for grinding and honing at a precise angle, just as it is customary todays for knives.

All associated programs ask for the jig diameter. They were obviously developed with knife sharpening in mind, so they silently assume a symmetrically round jig (at the spot where it rests on the USB at least). All past knife jigs fulfil this demand, and the diameter was chosen for simplicity and convenience.
The real value of interest however, is the distance from T-USB to the imaginary center plane that is constructed by the line through the center of the spine (of a knife) and the cutting edge (let´s call this the center plane for the lack of better words).

This is the parameter the program works with, because this distance is a crucial part in constructing the triangle that spits out the T-USB-to-stone value we are after; on a standard knife jig it comes out as 12 mm / 2 = 6 mm.
The graph here Calculations used for calculating SVM Knife Projection displays those relations quite nicely.

But note, this is a source of error: the older models of the knife jig used to have a 12 mm metal bar and thus a consistent diameter throughout. They had the potential of non-symmetric clamping, which would lead to uneven bevels. Its current successor was made symmetric, but has an inherently variable bar size due to its construction. Using it at the outmost rest will indeed yield 12 mm, but on the inner rest, for smaller knives, it will be more like 14 mm. This introduces an error probably overseen by many.

Fortunately sharpening of knives is not rocket science, a fraction of a degree up or down won´t hurt as long as the settings are consistent, repeatable and symmetric, but keep that source of error in mind particularly if you are the nit-picking type.

I used the SE-77 SE-76 square edge jig (in case this has changed over the years: I speak of the model ca. 2007) as a test candidate. The parameters needed for the program(s) are not obvious or readily measurable, so I looked into that.

The first parameter to determine is jig diameter. As mentioned before, the internally used value is the distance from T-USB to the center plane. In our case, the latter coincides with the top of the blade (there is no second blade side and there is no upper half of the jig rod). Consequently the choice for naming this parameter "jig diameter" turns out to be an unhappy one, but that´s how it evolved. Let´s call this real parameter center plane displacement for the exercise.

For the SE-77 square edge jig center plane displacement comes out as 24.5 mm 25 mm (see fig.1 "measuring center plane displacement"; measure the distance from the top of the blade to T-USB using a vernier). This is straightforward. This number is invariable and only needs to be determined once for a given jig.

According to the above explanations, this is only half of what the jig diameter parameter expects despite the fact that it internally works with exactly that number, so you have to enter double of that value, i.e. 49 mm 50mm. (Being taken for granted, this parameter accordingly does not receive particular attention in the above drawing. It is denoted by a circle around the cross-section of the USB.)

One more measurement we need is projection. Projection is defined as the distance between the point where the center plane meets the stone and a plane that is in a 90° angle to it that touches the USB bar at the stop screw (let´s call this stop screw plane, see picture). This is a bit tricky to measure. (Note that neither the jig axle's rest nor the jig stop's contact point are necessarily meeting T-USB. They are different points, but close. Refer to above mentioned graph). Thus directly measuring the distance from the USB's rear side to the cutting edge in parallel to the center plane with a vernier is not yielding the right result, since the SE-76's flanges protrude towards the operator and obstruct any direct access to the USB with the caliper's feeler fingers.

See fig. 2 "measuring stop screw plane to rear jig offset". Place a try square flush to the top of the jig. (Left or right of the stone the jig can be flipped forward or backward and stay put in a resting position). Its one leg is in parallel to the center plane. Measure the distance from the inner edge of the other leg to the USB with the vernier.

It turns out that this offset is exactly 5.5 mm 5.3 mm. (Again, measured on my older jig). The intermediate projection value measured with the caliper was 70 mm (See fig. 3 "measuring the intermediate projection value": use your vernier to measure the distance from the cutting edge to the rear side of the jig. Aim to be in parallel to the center plane), so the correct projection is 70-5.5 70-5.3 = 64.7 mm.

I chose to grind at 27.5 dps, and the T-USB value produced by the program is 26 mm (rounded) 25.9 mm (note: this is only valid in conjunction with the current diameter of my wheel, 198 mm), which is much smaller (about factor 3) than what one may expect for knives due to the much smaller projection.

I sharpened with this value, and after sharpening I checked the edge against the angle gauge notches on the WM-200 (fig.4: "controlling the final angle"); it fits perfectly into (one half) of the 55° notch. So this is another proof that the number method works universally.

A small appliance akin to the ones existing for knives could be made to mount the planer blade at a certain projection every time, in which case one could work with the very same setting over and over until the wheel diameter has changed. Even thicker or thinner blades would not make a difference, since the jig opens towards the bottom.

I later sharpened a plain chisel with the same method. Without going into detail (since the basic procedure is well documented), the angle turns out correct.

Have fun.

Edit: I updated the jig dimension measurements above after finding a more exact method.

I have a hard steel core clad with stainless. Looks and works great and comes very thin to start with.
Best of all worlds for starters.

Unfortunately (for the part in me that is eager for the stone) it will take a looong time until this one needs some serious maintenance.🙄

The majority of cheap kitchen knives is made out of stainless steel with a composition that varies minimally from the above quoted.
An attempt to shape them like you did, LeU, is prone to fail from a start.
They are very forgiving to mistreatment however. You can make them usefully sharp and they are cheap. Perfect for the average housewife.

Hard steels inevitably are susceptible to rust and are non forgiving. So there is no clear vote for either of them.
Not everybody wants to drive and maintain a Ferrari.

Yes indeed, making a wheel is a luxury.
The wheel from Hanns is absolutely competitive (apart from the fact that he is the only one who sells such a thing to my knowing ) and top notch.

Despite the fact that I got the specs as tight as possible (using generic tools), there is always a hair of play on the bore and the thing inevitably wobbles.

I observed the same thing with most grinding wheels. I believe it is not so easy to get a bore done to very tight specs, maybe the material shrinks or whatever.

This is why most sources for dry wheels sell them with bigger bores, say 32mm. It is a breeze to have a very tight fitting insert made on a 3D printer.

Maybe Tormek and all aftermarket guys should consider this.

But back to the wooden wheel. I did the usual fandango and re-opened the wheel, spun it and tightened it again - in vain.

Finally I got a piece of wood and gave the wheel a slight kick when the peak came round, and after two or three trials, it runs quiet. I will never open it again 

I also observed that comparably large flanges don´t help much for centering - to my astonishment.
Maybe blotters would?

[not]

I have come to the understanding that spot drills and center drills are the machinist´s choice for a lathe or any other device (like a mill) that has a very tight grip on the tool, plus an equally well fastened work piece.

They are a bad choice for the layman´s cheap drill press, let alone hand operated units, because they are not ground to any particularly special shape that would foster a good hole start.

As I (hopefully) layed out on my recent contribution ("Musings...") the hobbyist is far better off with a small (store-bought) drill with some form of web thinning (split point), followed by the final drill with practically any grind you like.

Since you seem to belong to the prior clientel and thus seem determined, the answer is: no, you cannot sharpen them on the Tormek if they are small.

Gadgetbuilder talks a lot about this subject. He advises against center drills for certain reasons and recommends sharpening spot drills to a 4F shape. He also explains several reasons to not sharpen them to the 90° or whatever acute angle they commonly have.
That all said, bear in mind that he comes from the lathe corner. I found that a short stubby drill I had sharpenend to those specs bears no advantage on a drill press, however a 4 mm (store bought) drill with split point was far superior for starting holes.

Drilling on a lathe is not the same as drilling on a drill press or manually.

Ah thanks that worked.

My separate honing wheel for any one interested. if the photo posting works!

Dan,

if you are monitoring this thread...

I finally got around to do an almost identical thing.
I made my own wheel. I did not like the way Schleifjunkies made the rollover.
The body is made of 30mm birch plywood (or beech, can´t remember), leather belt was bought and glued with fast curing and waterproof wood glue. This is a proven method for glueing Tolex. I spared the last centimeters out and finalized those with contact glue. The wheel is directional because of the crossover. As you can see, the meat side is outside.
On the picture, the wheel is virgin.

The holding bracket is made of cross-braced hardwood. Mounting is done with rampa inserts in case it turns out that the position needs to be optimized.

From a financial perspective, it is not worth to d.i.y., no way.
Note that I disabled the dry wheel part.

I am going to score another one of those machines (they are useless otherwise) and set up my felt wheel.

It is total luxury to not have to remove wheels all the time, because you ain´t never get them running as steady as they were before without a rigmarole.

Haha, I did:

Your search query did not return any matches.

I don´t understand the prerequisites.

Thank you very much.
What I like about this approach is that all commodities that have been established so far, like the number set-up (using one of the calculators), are applicable.

I would not appreciate to have to resort to the guesswork of using angle masters and the like. Apart from that, I suspect a non symmetrical grind could steer and deflect the axe during the cutting, which could be dangerous.

I have done an axe before free hand, and the angle turned out to be way too acute. The axe was useless. One chop and it had a huge dent.

I looked up Rick´s job. I like the laser bit, I will get one of those one day.
Good stuff too. I have never seen one of those axes in Austria.

Using the US-430 support bar, which I already had, sharpening the long chef knife was not a problem.

This is a case where the long support bar will be needed.

I modified my SVM-45 and horizontal sleeves of my T4.

This is interesting. Would you let us know more about this?

the brand new MB-102 (which combines the MB-100 and an FVB)

Now this I call a real step forward. The FVB functionality practically comes into the bargain...

From the picture, the guiding sockets appear a bit shorter than what the FVB or the XB-100 would provide, but I believe it works this way. Had I know this a few months earlier...
This may be the swan song for all FVB derivatives.

Indeed, for face-grinding this tool is indispensable.
Face grinding works with simple stones too, but what arises eventually is the question of trueing the side. The multibase together with the USB is not rigid enough to allow using the trueing diamond.