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A creative mind and a bit of ingenuity can go a long way, which is amply evident in all that Rich Colvin does. 

The manual for the RB-140 is here.  It states that the range of blade sizes it works with is 80-140mm.  But If the mounting shaft size is 12mm, as every other Tormek jig is, it will likely "fit" on the standard USB. From there, it could be just figuring out how to make it work.  28mm is pretty small (1.1"), so that could be your biggest challenge and Rich's jig may be a better approach. 

Do a search on the forum for the jig, using the term "RBS-140 Round Blade" and read what discussion there has been about this jig and round blades in general.  It does return some irrelevant stuff. 

[square with the sides of the plane blade]

Good day to you too ! And welcome to the forum.

If everything is square and your blades come out out of square, then there might be an issue with your technique. So if you keep on grinding the same way, you will probably keep sharpening out of square.

What I'd do is skew the SE-77 so you grind your plane blade back towards square. It is explained on page 127 of the SE-77 manual

I agree with tgbto and John.

Adjust the it using the skew screws -in very small increments - until you get the front edge of the grind square with the sides of the plane blade.  But it is unclear to me what your reference is here.  I think I'm reading square to the jig and square to the wheel. The only thing that matters is square across the cutting edge relative to the blade sides. 

Also, as tgbto points out, technique has a lot to do with how squareness turns out.  Before the skew adjustable jig came out, one way to affect the grind was to put more pressure on one side of the blade.  Even with the skew screws adjusted, I find I still have to use controlled pressure.

Use the black marker trick to help show where grinding is occurring, as you work your way back to square.  I put black marker on everything, every time I put something to the wheel, knives, scissors, drill bits, plane and chisel blades - even things that aren't cutting tools.

John mentions using a small square, which is exactly right.  But, make sure the small square is square.  I've seen mention and pictures of 3D printed small squares, but I wonder just how square they are.  The best tool to use is something precision, like a Starret 4" adjustable square, or a very small precision machinist's square.  I like the Starrett or Lee Valley Small Double Square, as projection of the scale can be adjusted, based on the projection of the blade from the jig.  Tools like these are not cheap, but I find they are worth it. 

I was quite unclear. Adjusting was the wrong word maybe.

How do you clean your sj stone?

Ah, yes, that is quite a different question. 

I would definitely not use the Tormek grading stone.  Some like the Nagura stones, but I find even them to be too coarse, removing too much SJ wheel material.

Instead, I have been using Sabitoru "rust eraser" pads.  The website linked here shows three grits available, but I've only used two that came in a pack from a different source.  Cleans the surface beautifully, removing nearly all traces of metal and black marker. Images below show before and after cleaning with the Sabitoru pads. 

The SJ stone is very fine and also quite fragile. I would dare touch it with anything that isn't reasonably parallel to the USB.

Even when recently trued with the TT-50, it remains quite smooth and polishes well. There are precautions to take (such as never exit the stone with the TT, always hit the shoulders moving into the stone. You can find several posts on this topic.

If you want to grade it as fine as you can, I'd suggest a very fine diamond plate held in place with the SE jig, as seen in Wootz's stone grading videos.

Many have found that putting a radius (chamfer) on the corners of the SJ stone helps a lot to prevent chipping of the edges, both in sharpening, but more so for truing.  The grading stone works well for creating the radius.  A fine diamond plate (~1000 grit) is what I use for reconditioning the surface of the SJ but I'm not sure that it is coarse enough to put on enough of a radius. The chamfer shown in the image below is barely adequate. 

I have also found that it is possible to exit the edge/side of the SJ wheel while truing, if two things are done:  1) a healthy radius exists and 2) travel speed of the truing tool is VERY slow. 

Please post links to those earlier discussions.

such as Norton 3X

Norton do not recommend 3x for HSS so that is not an option. You will need the green Silicon Carbide wheel.

Interesting.  John, could you provide more info on this, please?  I've searched and found several sources saying the K grade 3X wheels are suitable for HSS, but have not found any yet that say it isn't.  If they aren't, it will be good to know, but the point of my post was that this type of grinding wheel (if suitable for HSS) is a viable alternative. 

The other options, such as belt grinders and bench grinders can be faster

Again not an option since the planner blade needs a precise parallel edge.

I fully agree and didn't mean to imply that these are an option for planer blades.  I've quietly scoffed to myself a few times when I've seen references to using them for it.

The regular wheel is Aluminium Oxide which is softer than your HSS and will not effectively cut the HSS. You will need either the black (Silicon Carbide), diamond or CBN. I use diamond for mine but CBN will do perfectly fine. If they are nicked then you probably need to go to an 80G to remove the nicks. My last sharpen tried to remove the nicks with the DC but it took ages. I have since bought an 80G CBN. But for simply resharpening with use the SB, or DC, DF through DE or CBN equivalent. 

I agree with the above, particularly on going to a much coarser grit for damage repair and heavier metal removal.  After trying several alternatives, I have also gone to 80 grit CBN, 10" dia., 2" wide wheel. 

However, of all the other things I tried, I think the next best one is a standard grinding wheel (such as Norton 3X) in 64 or 80 grit is a very effective and low cost option.  It provides faster metal removal and preserves the water bath benefits of the Tormek.  The other options, such as belt grinders and bench grinders can be faster but all product dry grinding grit/dust and carry risks of overheating blades, etc.  I first tried 8" standard grinding wheels, but switched to 10" for consistency with the 10" wheels on my T8. 

My point is, if investing in coarse grit diamond or CBN is a bit too spendy for you, there is an effective, low cost alternative. 

How large is the delta between the T8 shaft OD and the wheel hole ID? Is it large enough (>0.4mm) so that one could simply 3D print a sleeve (e.g., using a 0.2mm nozzle) to slide over the shaft whenever mounting a wheel, or perhaps turn a thin sleeve on a lathe?

I would be wary of anything that might increase strain on the stone, as it seems to be rather fragile. I wouldn't want to initiate a crack in the stone when the stones expands ever so slightly because it is wet.

As to the wobble in the stone, tightening the nut when the label is upright has become second nature. I don't even think about it anymore, it really is not that much of a loss of time.

The SJ wheel is tougher than one might think, given how friable/soft it seems to be.  By no means should it be handled roughly and without care, but they can survive even severe cracking and still be usable. 

In 2018, my SJ wheel fell off of a folding table that did.  And in the process got soaked with acetone.  It was cracked in several places well beyond anything I could image it would survive.  It did:
Farmers Markets Ends in Disaster - or - Don't Drop your SJ Stone

The cracks closed as the acetone evaporated and I was able to true it and use it as though nothing ever happened.  There are videos in this post of the stone being trued and a slow rotation view of the surface after initial truing. 
Truing Damaged SJ Stone (the one we thought was beyond hope)

Even so, I would not do anything that might induce cracks unnecessarily, which I consider attempting to install a bushing to be. 

Further, I think that using the label alignment trick, with truing and use in that orientation should take care of any bobbing up and down of the outer surface.  I also think that lateral wobble is immaterial to the sharpening function/action, considering that the effective "wobble", that is side to side movement of blades across the surface, are far more extreme than any little bit of lateral movement in the wheel. 

In short, I think attempting to stall a bushing is a solution for a problem that does not exist.

Rick

These wheels cost around $70US, and one is enough.

In France, I couldn't find those aside from Amazon, priced at a modest EUR 200. The BDX line of wheels is more widely available and more reasonably priced. Does anyone know how they compare to the 3X ?

I think just about any standard grinding wheel, in the 64-80 grit range will do about the same.  I was gifted the 8" Norton wheels that I first used in this manner, which were great.  Then I was gifted a no-name/don't even know the grit 10" grinding wheel.  It works every bit as good as the Norton and I much prefer the 10" diameter as it is more similar to others on my T8. 

These standard grinding wheels are trued just like any the SG or SB wheels using the Tormek Truing Tool.  An excellent choice for anyone wanting faster metal removal.

Norton 8", 64 grit wheel on T8 sharpening a drill bit

10" standard grinding wheel on being trued on a T8

It's not so much the spine thickness as it is the "thickness behind the edge".

...snip...

And as the same knife is ground with repeated sharpenings, the "thickness behind the edge" begins to increase as the bevel migrates toward the spine.  This would result in much smaller differences, hardly noticeable until it has gone a long way and probably not nearly as much as shown in the OP's photo. 

I'm kinda confused. I bought the Tormek T-8 with the knife angle setter and the knife jigs. I follow the tuturials the same as on the YouTube videos.

But the thing is, their wheel is turning away from them and the knife edge. But my wheel is turning toward me toward the knife edge.

I have the 600 grit diamond wheel. But that wheel will get damaged if I sharpen with the wheel grinding toward the edge.

So is there any way to reverse the spinning direction? Because obviously I can't sharpen knifes like this.

I think it is simply a matter of which side of the unit you are standing or sitting on.  Viewed (and working) from the front, the wheel is turning away from you (edge trailing).  Viewed (and working) from the back, the wheel is turning towards you (edge leading).  Those who work from the rear of the machine typically stand.  Those who work from the front can stand or sit.  I sit. 

I've not heard before that the diamond wheels will be damaged by edge leading sharpening.  I've been doing it that way for years and they all still work fine (DC, DF, DE).  This Tormek video shows a knife and a chisel being sharpened edge leading, starting about 0:22 - 0:25. 

Where did you get that idea? 

Rick

...snip...
      it appears there is more than one way to achieve his results.  Technique is the key.

I have to agree, just last week I got a 67 BESS result using the composite honing wheel followed by stropping on a hanging leather strop.  The latter step contributes significantly to the final sharpness.  Got some others that hovered around 100.   All were polished on the SJ wheel prior to deburring. 

Anyone ever used their diamond wheels for grinding glass?  Diamonds supposedly cut everything and may be the only thing that would work on glass.  Only talking about taking small amounts of of an edge.  I'm thinking on the flat side of the wheel. 

Hello, I bought the DBS-22 Drill Bit Sharpening Device. But I couldn't do it as described in the videos. Let me tell you, after the primary grinding, I do the secondary grinding, but I can't provide parallelism between the two sharpenings. I wonder where I'm going wrong?

Please tell us which videos you are referring to has having watched.  I would only trust the ones done by Tormek, in particular the one by Alan Holtham. 

Pictures would help a lot.  Hard to have any idea what you are saying about parallelism without seeing it.

You have to very carefully follow the instructions. Any slight deviation can lead to disaster. It took me a few drills before I was getting perfect results. Use the instructions that came with the guide and follow them very carefully and you should be good.

Also note that if you are taking out bad chipping then you may need to do the primary grind, then reset the drill and re-do the primary grind again since the leading edge may have rotated with respect to the jig if a lot of material is removed.

I agree that the instructions/process has to be followed quite carefully. It is easy to miss steps or not do them appropriately/adequately.  Slow and deliberate, checking every aspect, until you get proficient. 

I also agree that if much grinding is done on the primary facets, repositioning the drill to realign and regrind the primary facet is often necessary. When I know there is a lot to be taken off, I have sometimes rotated the drill so that once that material has been taken off, the primary faced.  Sort of "advancing" it. 

Rick

In fact, if bad chipping or broken flutes, etc. need to be taken out, it will likely be better done on a conventional high speed grinder to do the heavy metal removal before taking it to the Tormek/DBS-22. 

Good evening
I've got a T8 with DBS22 set up as per the instructions and had ago at sharpening a few drills, all have negative clearance angle so they will not drill holes!, I've trawled through a few sites on you tube, found one with exactly the same issue but the question was not answered (response's went off on numerous tangents, none related to the initial question)
Looking at the drills, it seems that something is out by 180 degrees, what should be the cutting edge is now the flank, so I have drills that may cut in reverse!
I've been hand sharpening for 55 years and thought I would give the Tormek system a go but it's not going very well, any suggestions what is going wrong?

Posting some photos of bits you are having trouble is the best way to get the feedback you are after.  Given the notion things are out by 180º, I'd say Rich Colvin's comment about flute alignment should be looked at carefully.  I found that it sometimes takes "re-alignment" of the flutes if much grinding has occurred, as the flute is ground away, it looses its proper alignment. 

Alan Holtham's video and Joseph Mazoff's article were game changers for me and primary reasons why I bought a T8 in the first place. Like, Ken, I don't sharpen drill bits very often, but when I do, I watch Alan's video to refresh my memory.