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Does the wheel actually wobble on the shaft, or is the wobble due to the shape of the wheel itself?  If the wheel is loose on the shaft and wobbles, it may be that the arbor hole has worn and/or is no longer round.  If it does not wobble on the shaft, and the sides of the wheel wobble, as shown in your video, that would appear to be the result of the shape of the wheel. 

I've read a few times here in the forum the opinion that side wobble, even as much as shown in your video does not really adversely affect sharpening, as long as the outside diameter (OD) of the wheel can be trued, presumably using the Tormek Truing Tool.  Do you have one of those and have you tried truing OD, which is the only surface that matters on that type of stone. 

Not sure I'd go for that job.  Much depends on your setup and experience.  What equipment do you have?  Do you already have the drill bit sharpening jig and have you used it?  What grinding wheels do you have?  Just the standard SG-250?  SB-250?  Any diamond or CBN wheels?  How many drill bits have you sharpened? 

If you had the jig and had sharpened a few drill bits with the equipment you have, I's suspect you already have a good sense of the task. 

The standard SG wheel is really not adequate for the task. Most decent drill bits are High Speed Steel (HSS).  Tormek came out with the SB wheel specifically for the task of sharpening HSS because the SG won't "cut it".  I found the SB wheel wasn't agressive enough and went searching for be other alternatives.  I went through several, including Tormek diamond wheels (DC), 180 CBN grit, standard bench grinding wheel fitted to the Tormek and running in water (T8), slow speed bench grinder fitted with Tormek tool rests/jig, variable speed belt grinder fitted with Tormek tool rests/jig.  My last acquisition is a 250mm diameter, 80 grit CBN wheel on the T8.  This last one appears to be aggressive enough, but I haven't tried it with drill bits yet (worked great on plane blades). 

Even so, I think the Tormek may be too slow for this sort of volume task.  I think a better alternative would be something like the Vevor MR-13 A or B sharpener, depending on if you want to be able to web-thin (A model) or split-point (B Model).  About the same price range as the Tormek drill bit jig (if you don't have it yet) but way faster, particularly for volume work.   

The grind finish is not nearly as nice as factory or what can be achieved with a full suite of Tormek wheels, but adequate.  It is most effective at rapid metal removal (something the Tormek is weak on) and I suspect given the quantity you're looking at, many of the bits will be burned/chipped/broken and require a lot of metal removal. I use the Vevor Model B for roughing bits and finish them on the Tormek, but I doubt I'd try doing that for such a large quantity of bits as you are looking at. 

You are on this forum and there is a drill bit sharpening specific subforum, so go there and do a bunch of reading about what others have experienced.  I've posted a bunch there.  Also, there are several discussions on metal machining forum and quite a few YouTube videos reviewing drill bit sharpening like the Vevor. 

Alan Holtham does an excellent job demonstrating how the Tormek jig works here, but that is not the whole story.  Mr. Pete does a great job demonstrating the Vevor sharpeners, Model A and Model B.

Rick

True it enough to clean up to outer surface and chamfer/radius the corners, putting a larger radius on the chipped side and use it. 

I suffered what I thought was a fatal accidental fall of my SJ-250 when the table it was on collapsed at a farmers market in 2018.  I posted about it here then.  I've been using it ever since with not one single issue due to the cracks and chips. 

Here it is three years after
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And here it is in 2024
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With a little bit of time, the acetone evaporated and the cracks closed back up and are barely discernible now.  I don't even think about the fact that it was once cracked and chipped what appeared beyond repair or continued use. 

Rick

Thank you for the kind welcome and helpful replies gentlemen.

The threads which retain both of the wheels on the shaft are definitely Right Hand, 12mm X 1.75mm pitch, a standard ISO 12mm nut screws on easily, I have just run a good 12mm X 1.75mm die on the threads at the stone wheel end AND the honing wheel end, which suggests to me that this is a home made (or improvised) shaft. The shaft is exactly 16mm diameter steel. ...snip...

I believe the right hand threads you see are what was standard, back in the day. Thus, the shaft may or may not have been "home made".  That the shaft is 16mm dia. is curious and could be an indicator of non-standard. What part of the shaft is 16mm?

The "new" shaft version has the left hand threads and EZ-Loc nut, which a major reason for getting it instead of fabricating a new one with right hand threads.

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I will drill out the shaft from the stone wheel later and see what the situation is with the remaining hole in the stone wheel, I am not expecting a good outcome, the crush effect of expanding rust has probably damaged the stone so I expect to have to sleeve the hole then bore the sleeve accurately to retain concentricity.
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Good luck boring out the shaft and if you have to sleeve the hole, good luck boring out the stone to make space for that sleeve.  With the "price" of the machine to you, you may be better served just buying a new "modern" standard grinding wheel (SG-250). 

Welcome to the forum.  Nice acquisition.
 
The replacement shaft is stainless steel, so I believe it would behoove you to get it from Tormek, as it comes with the new, easy lock nut as well and won't corrode, even if your grinding wheel has rust embedded in it.  I love turning and milling stainless (at least some alloys of it), but I is not worth the work in this case, I feel. 

There have been several folks who have restored older Tormeks and there is extensive discussion around those threads that could be of great interest to you. And just spend some time, if you haven't already, just reading the long history of discussions, regarding all aspects of the Tormek.  Lots to learn. 

I highly recommend getting a Truing Tool.  Much easier and likely more accurate than truing on your lathe.  I have two lathes and I would not want the grinding grit getting on the ways or other moving surfaces. 

Rick

I decided not to glue in the new sleeve. I used POM and made the sleeve press-fit:

Have you trued the grindstone? Have you tried sharpening something to see if the sleeve doesn't slip?

If you do need to glue it you would of course need a water proof glue. And you would have to make sure the grindstone is good and dry. I'm thinking maybe gorilla glue?

Hopefully, the sleeve is short enough (or can be shortened if not) so as to not interfere with the thick washers on both sides of the grindstone, which should grip the wheel and not the sleeve.  Not much sticks to delrin (Polyoxymethylene), so if one were to try to glue it in place, it would need to be deeply grooved in an angular or lengthwise a way such that the dried glue would act as keys, locking the sleeve in place.  The circular grooves in the photo the OP showed may not be adequate. 

Rick

Hello Rick,

POM (Polyoxymethylene) is a plastic that, ...snip...
Andi

Ah... Good old Delrin... or known by some as acetal. 
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Love working with this stuff.  Have loads of it.  Turns and cuts really nice, holds its shape and slippery.  First learned of this stuff in the 1960s, working in my father's machine shop. Just never heard its chemical name.

Rick

Good fix.  What is "POM", please?  It is an unfamiliar term for me.  I'm surprised you were able to find something that fit so nicely in the hole in the stone and that has a 12mm center hole.

Rick

I doubt very much you could true the side of the grindstone with the grading stone. Perhaps a diamond plate?

Another option might be to use spray-on contact cement to glue a full sheet of sandpaper to a flat table top, remove the grindstone, and rub it on the sandpaper. A flat surface can be created with a scrap of 3/4-inch MDF. Cut it a bit larger than the sheet of sand paper and fasten it to your benchtop with a few drywall screws, countersunk, of course.

This is probably a reasonable path for flattening the side of the SG wheel.  If not careful, sanding one portion more than another could cause it to not be perpendicular to the arbor hole/outer surface (which is trued by the Truing Tool).  Such non-perpendicularity would cause the side of the wheel to have a wobble, which might not work well for some sharpening operations.

Plus I realized afterwards that a serration is not a half-circle, but rather a portion of it, so the diameter can be wider than the pitch.
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A radius gauge set, like below, is the right tool to measure the serrations. Match the curvature of the gauge to any portion of a internal or external radius and read the measurement from the stamped markings. 

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I know that's asking a lot, no worries if you can't. Thank you again for the time you've already devoted to this.

Nick.

Didn't think I'd be back at it with these knives for quite a long time, but it turns out I missed a paring knife and failed to grab a hooked/beak shaped paring knife from the box, so two more today.  Per the request, I meant to get both after grinding and before the SJ.  Only wrote down one, 567, but I'm pretty sure the other one was pretty similar.  Kind of a surprise they are so high. 

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Rick,

Thanks for the extensive testing and for sharing your results.

This subject of SJ and honing has been of interest to me since my first session with a SJ.

Why do you call what you do with the SJ wheel "honing", when the (300ish) BESS scores clearly indicate that there is still a burr ?

Also, do you know what the BESS scores were right after initial grinding ? Do you think you could get a quick order of magnitude of the BESS score after another grind on the *SG* wheel at the same angle ?

I know that's asking a lot, no worries if you can't. Thank you again for the time you've already devoted to this.

Nick.

That's a good question.  Best I can say is, I was taking the mindset that the SJ wheel could be used for honing, so just called it that.  Was it someone at Tormek that made that claim?  I've always thought of it as polishing rather than honing.   

I don't have much on the scores after grinding, before putting them to the SJ.  369 and 602 is all. 

Should change the Subject to "SJ Wheel Honing". 

Took another stab at it, but this time, mostly just used the SJ wheel for honing. Eight identical Wusthof Dreizack Grand Prix steak knives.  First one, the SJ wheel was used at the grinding angle (16º) and then the rock hard felt wheel was tried at two angles, 16º and 17º, followed by stropping on a hanging leather strop.  Not much better than before.  Subsequent seven knives only the SJ wheel was used for honing, again at 16º and 17º.  Knives 2-4 were stropped after honing.  Knives 5-8 were honed after 16º and after 17º.  A little mixed up, but hopefully something useful.

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Honing with the rock hard felt wheel degraded the edge, similarly to earlier.  Honing with the SJ wheel at either 16º or 17º followed by stropping on a hanging leather strop, while starting out really high (BESS 250-389) stropping improved to sorta-kinda removing the burr in some cases (BESS 100-120) and almost in other cased (122-136).  Honing with the SJ wheel at 16º and then at 17º does not appear useful, but it is hard to conclude this due to the leather strop honing between those two.

From this, I think I'll dispense with using the rock hard felt wheel and just use the SJ wheel for honing, if followed by the hanging leather strop.  Might be worth trying SJ honing at 2º over the grinding angle and maybe at a negative from the grinding angle (-0.5 to -1º). 

Rick
 

Thanks for this Rick. Interesting.
From what I understand (and I may be wrong in this) your Bess scores would indicate that complete burr removal has not been achieved. This is not a criticism of you because you have freely given this info at cost of time and effort to yourself to try to answer some questions. Researching.
From somewhere I remember Vadim stating that a score of over 120 Bess is indicative of incomplete burr removal.
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Shucks, isn't that embarrassing...    As you say, it is good information.  I take no offense. 

At some point, I'll have to re-evaluate my process, see if there is something I'm not doing the same, or if something else has changed.  I'm pretty certain I'm getting good burrs all along the edges, so it must be in the honing.  Unfortunately, the best I'll get for a while is to maybe make a few more passes in the SJ and honing steps or more pressure with these remaining knives.  Too much else on the plate and frankly, what I'm getting is good enough for getting by. 

Be well,

Rick

I've been using a rock hard felt wheel with 1µ diamond paste for years with what I am satisfied with as good results, typically around BESS 100, but I no longer check the actual BESS readings as it has been so consistent.  I'm only sharpening standard steels.

Looking through the discussion, I do not see where anyone says much about the other aspects of the setup, some details that Vadim established as important.  Using a Frontal Vertical Base for setting up the USB for clearance and angle control during the honing process. And angles set higher or lower than the grinding angle, depending on the type of steel.  It may be reasonable to assume that you guys are also doing this, but it would be good to know this is the case. 

Because I'm only sharpening standard steels, I'm always using an angle 1º to 2º higher than the sharpening angle, which is usually around 16º.  My grinding steps are 180 CBN, DC, DF, DE Tormek diamond wheels, Tormek SJ and then the rock hard felt/1µ diamond paste and stropping on hanging leather strop. All the grinding steps are done at the same grinding angle, from the read USB, edge-leading.  Only the rock hard felt wheel angle is changed for honing, from the FVB/front USB, edge-trailing.

Hearkening back to this conversation and the two following that related to it (#7 and #11), I decided to do a little testing.  I have about 14 knives from a friend's set of Wusthof Dreizack Grand Prix knives.  I've sharpened these before, all at 16º and it is time for a redo. I wanted to test for any difference between "grinding/polishing" with the SJ wheel at the bevel angle versus 2º greater, both followed by honing on a rock hard felt wheel with 1µ diamond paste and then stropping on a hanging leather strop.  Here are the results:
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First off, I must eat a little crow.  My claims of consistently achieving 100-110 BESS are a bit off the mark, at least with the way it is working for me now.  Not sure what is different, but that is for another time.  One thing that I am unsure of is that I strictly followed the above regiment.  I noticed afterward that the wheel diameter in the calculator for the SJ wheel may have been 254mm (that of my 180 grit CBN wheel and RHF wheel) instead of the SJ wheel's actual diameter of 246.7mm.  Not sure of that, but I have eight more steak knives to do, so if I'm feeling up to it, might try this test again. 

On the the results. 

1) SJ wheel at the grinding angle seemed to produce slightly lower BESS scores than at 2º above the bevel grinding angle.

2) Honing all at 2º higher than the bevel angle improved sharpness for all but the SJ at the angle plus honing showed the lowest scores.

3) Stropping significantly improved the set ground with the SJ at 2º higher and resulted in BESS scores relatively similar to the SJ at the same angle as the bevel.

4) Stropping did not improve sharpness for the blades ground/polished at the same angle as the bevel beyond that achieve only with honing on the RHF wheel with 1µ micron diamond paste.  But stropping did seem to improve sharpness of the blades both SJ ground and honed at 2º above the grinding angle.  These samples are far too limited to make very strong inferences, however. 

Rick