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Genius of you don't mind me saying. My son has a 3D printer and he whipped up these for me, as well as the screw knob you referenced. I had to get the heat nuts which came earlier this week. I bought a kit of heat nuts, well two kits, one for my son.

It worked as advertised and produced a perfect edge. The router was an old Stanley from about 1910 and belonged to my dad an has his initials on a knob. I am guessing that he bought it new when he was an apprentice. I am so pleased that the blade is now looking as new thanks to your jig.

Really pleased it worked well for you John (and also thanks for the review on printables.com)

I don't have a lot of faith in grit numbers, at least as the only determining factor. I have found that my DC-250 360 grit diamond wheel cuts faster than my 220 grit SG-250, even after being freshly trued. Also, I do not consider the DC especially coarse. Have you considered using your 80 grit CBN wheel wet with your Tormek? I used mine this way with Honerite Gold anticorrosion solution before I acquired my diamond wheels. Looking at your website, adapting the bore size and thickness to the Tormek would not seem difficult for you.This is not as fast as dry grinding; however, it is noticeably quicker that regular wet grinding and it is both cool and dust free.

I hadn't considered that, but I will now 

It would certainly be nice to have a grit free grinding method.  The CBN wheel is smaller in diameter, but I imagine that would be okay.  I'll have a look to see what the bore is at some point (and hence whether it can be fitted to the Tormek).

Like CB, I do not own a BGM-100.I do have the parts; however, for the rare occasions when I want a coarser wheel, I use a Norton 3X 46 grit wheel wet with my Tormek. I am not a fan of the BGM-100 used dry. In my opinion, dry grinding defeats the purpose of the Tormek.

I completely understand that sentiment if the Tormek + Norton 3X works for you. I haven't found a good UK source for coarser Tormek wheels (like the Norton 3X one you mentioned), otherwise I might have bought one. I got the 1450 rpm grinder as a result of frustration with the Tormek (which I'd bought primarily for regrinding bevels).

I'd been regrinding a few tools (notably 6 mm thick plane blades) to a different angle & in the end had given up: it felt like the Tormek was going to take all day to regrind the bevel, either with the standard wheel or the coarse diamond one.

With the 1450 rpm grinder & an 80 grit CBN wheel, it was done in a few minutes, albeit requiring frequent dips in water. At least it runs a lot cooler than a 3000 rpm bench grinder: dipping in water is every minute or so rather than every few seconds.

Right now if I was ever forced to sell either the Tormek or the 1450 rpm grinder + BGM it would be a no-brainer: the Tormek would go first (but I'd keep the Tormek jigs to use on the 1450 rpm grinder ).

Tormek has a patent on the TTS-100. The two metal wheels automatically with diameter changes, including switching from 250mm to 200mm wheels. I don't worry too much if the bevel of the coarse wheel is identical with the final wheel. The coarse wheel is for rough work.

Ken

I'm really interested in understanding this better. I'll have a play with the maths & see what comes out.

Thanks Ken, that's interesting.  The TTS-100 does sound like it might work well for consistent set-up.  How consistent is it across different wheel diameters?  If, for example, you rough ground a tool on a 150 mm bench grinder with the BGM thing and then took it across to the Tormek with a 250 mm wheel, would you get the same bevel angle?

The reason I ask is that only this morning I was regrinding a scrappy old chisel and I used my calculator to set up the jig for rough grinding on the bench grinder with the BGM and then moved across to the Tormek (resetting the projection with the jig) and the angle was pretty much spot on, so the Tormek work was a matter of seconds.  It would be good if the TTS-100 can achieve that as well.  Maybe I'll have to add a calculator for custom angles with the TTS-100!

What I've since done is played around with the calculator a bit and I worked out that if I set the Tormek (250 mm wheel) up with a 33 mm setting tool (so 10.5 mm gap) and the 1450 rpm bench grinder (200 mm wheel) up with a 40 mm setting tool, then the protrusions work out roughly the same (at least for the two angles I'm most interested in: 20° and 25°).  With that set-up, I can go directly from bench grinder + BGM to Tormek.  Of course that would have been a heck of a lot easier if I'd bought the T-4 with the same size wheel as my bench grinder!

Despite saying I wasn't going to do it today, I've added tip angles to the calculator: the maths was really very simple indeed so it didn't take very long at all.

A bit more on bevel vs tip angles that will hopefully answer your question along the way...

I'm using tip angle to refer to the angle right at the tip, straight off the Tormek and bevel angle to refer to the line that joins the cutting tip of the bevel with the back edge of the bevel:

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Let's say I want to sharpen a chisel with a 25° cutting edge.  There are different ways I could go about this: I could target a 25° tip angle or I could target a 25° bevel angle.

Let's target a 25° bevel angle.  I put 25° into my calculator and set up the Tormek accordingly.  I then grind away a hollow bevel.  Once I've done this, I plonk it on my waterstone and fidget it around until I can feel the tip and the back of the bevel lying on the stone:

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In theory I could do this in a honing guide as well, but to get exactly the right angle could be a bit difficult.  Having said that, as long as it's roughly the same angle as ground in the Tormek (i.e. I use my Tormek calculator for the Tormek angle and my honing guide calculator for the honing angle), then it should be close enough that I can get to the finished angle without too much bench stone work.

Once I've rubbed it back and forth on the waterstone a few times, the front and back of the bevel have been worn away and now the tip angle is the same as the bevel angle (25°):

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Another way I can approach this (and probably the way I do most often) is to grind it to 24° (or lower) bevel angle on the Tormek and then put the chisel in a honing guide at 25°. That is equivalent to tilting up the blade very slightly and hence I take away a bit of steel at the tip but not at the back of the bevel, and end up with a 25° secondary bevel.

This latter method has the advantage that the next time I sharpen the chisel, I just go to the bench stones and grind at 25°, gradually increasing the size of the secondary bevel until it's time to regrind the primary bevel on the Tormek.  As I'm only taking material off near the tip, the resharpen process is very quick (less than a minute usually, and about the same time with or without a honing guide).

If I'd targeted a 25° tip angle on the Tormek, but still wanted to finish with a 25° secondary bevel off the stone, I'd have a lot more material to take off at the back of the bevel before I'd be able to touch the tip (this was modelled with a 200 mm wheel):

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Of course if I was happy with going straight from the Tormek to using the tool, then the tip angle is what I'd be interested in.  For me however, it's much, much quicker to resharpen an edge using a bench stone than it is to using the Tormek, so I want to be able to maintain the edge without the Tormek: the Tormek comes out again when I need to recut the primary bevel.

The maths associated with the tip angle is quite a lot simpler than the maths for the bevel angle, so I can't see any reason why my calculator can't do both.  I'll need to do some more detailed drawings explaining the difference and why you would want one or the other, so I doubt I'll get it updated today (I spent far too much of Saturday working out the maths for the bevel angle and I'd like to do something else with my Sunday!), but I'll post again on here when it's done.

Thanks for the interest and the very good question!

The reason for the tool thickness having an effect is different for a honing guide to the SE-77.

As you've read, on the honing guide it's because of the protrusion being measured from a different face to the reference face.

On the SE-77 it's because the grinding stone is circular rather than a flat surface. As the tool gets thicker, the inner end of the bevel moves around an arc, slightly changing the angle. The effect is small, but there is an effect.

Does that make sense? If not, I can draw a couple of diagrams to make it more obvious.

I guess it does depend on what you define as the bevel angle. As I'm usually taking chisels to a bench stone after grinding on the Tormek, for me it's the angle created by a line joining the two ends of the bevel. If you're only using the Tormek, it's arguably the angle at the tip, which won't change with tool thickness I think.

[quite]

Setting a tool in an Eclipse style honing guide for a given bevel angle is really quick: shove the tool in, offer it up to a pre-made stop, tighten the guide.  Even without a pre-made stop, using one of these edge distance gauge things things makes it very quick.

By contrast, setting up the SE-77 square edge jig requires using the WMB-200 and squinting to see whether the angle is right while you tweak the support bar up and down. That felt to me like a bit of a faff, so I thought I'd figure out the maths that gives the protrusion for a given support bar offset.  It ended up being quite complicated, but I like maths, so that's okay 

Anyway, what that ends up with is the ability to set the support bar to a particular distance from the wheel (which is easy with a setting tool a la Micha Schmid and Keld Petersen) and then set the tool protrusion in much the same way as you can with an Eclipse honing guide.

Unfortunately, it's not quite as simple as that as the wheel diameter and tool thickness have an effect.  For most practical uses, small changes in wheel diameter can be ignored, as can tool thickness changes so I think it's okay.

Anyway, having done all the maths, I thought I'd turn it into a calculator and stick it on my website (so it runs in a browser and doesn't need any spreadsheets or other software installed on your PC).

If anyone is interested, the calculator is here:

https://www.cgtk.co.uk/woodwork/calculators/tormeksquareedge

There's also one for manual honing guides here:

https://www.cgtk.co.uk/woodwork/calculators/honingguide

I'd welcome any comments

Screenshot:

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I really see no reason why the DBS-22 would not work unless they are made from some metal composite which is extraordinarily hard to grind.

They're HSS, so I'm not concerned about the Tormek grinding them.

The stuff I'd seen on the DBS-22 seemed very focused on conventional twist drills & I wasn't sure whether any difference in geometry would be significant (as you can probably tell, I don't know much about drill tip shapes).

This is my little collection of spot drills that I'd love to be able to sharpen:

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I probably use them more than any other drill bits as most holes are started with these bits.

This is the best photo I could take (of a 12 mm spot drill) showing the tip geometry:

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Sorry it's blurry: they're hard to photograph!

This photo shows the lengths of all the spot drills (3 mm, 4 mm, 5 mm, 6 mm, 8 mm, 10 mm and 12 mm diameter):

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The grid on the paper is 5 mm squares.

Just in from support:

"Hi Ken.
You need the protrusion and at least 1/3 of the length inside the drill holder. 2-2,5" in length is minimum. Do you know the length of the drill bits?
Have a nice day."

Ken

The shortest drill bit is 50 mm (so about 2"). The bigger sizes are a bit longer.

...
As a side benefit, they're sharpened at 90°
...

The DBS-22 manual on page 4 says:

Centering drills usually have a 90° point angle.

Might be a clue that it will?

Sounds promising, unless it means centre drills (for drilling centres in the lathe). These have a point (I'm not sure of the angle; I can check when I'm next in the workshop) and a short narrow section. They then have a 60° larger section for cutting the centre itself.

Having said all that, centre drills are very short, so I'd be surprised if you can hold them in the jig. Also, I tend to break the fragile tip long before they go blunt, so I probably won't ever need to sharpen a centre drill 

For that matter, spot drills are quite short too: perhaps that's a limiting factor regardless of geometry? My smallest spot drills (3 mm diameter) are about 50 millimetres long I think; when you set the drill protrusion with the stop on the DBS-22, how much sticks out of the clamp?

I'm wondering about getting the DBS-22 sometime soon.  I have quite a large collection of spot drills and quite a lot of them are blunt now, so I'd love to be able to sharpen them.  Can the DBS-22 sharpen this sort of thing?

Example of the type of drill I'm talking about: https://www.scribd.com/document/276985270/Nc-Spot-Drills

If you want to send me one, I will try to sharpen it on my DBS-22 and send it back to you. If interested, PM me.

Thanks for the very kind offer Rich, but your profile suggests you live in Ohio & I suspect that sending a drill bit across the atlantic ocean & back again will cost too much to be worth the hassle.

[a lot]

...snip...
except for drilling centres in the lathe, obviously).  The spot drills are even better at starting in the right point than centre drills and they are a lot more robust.
...snip...

If the latter statement above is true, why would you not also use them for drilling centers on a lathe? 

Rick

Because the point is 90°, whereas centres are 60°. Also, the little nib on a centre drill gives oil somewhere to go when you push the dead centre into the hole made by the centre drill.

Note that this is for skewed chisels (as used by woodworkers for cleaning out dovetail sockets etc), not skew chisels (as used by woodturners).  Skewed chisels (like these ones) have a single bevel at a steep angle and make it much easier to get into the sides of dovetail sockets than straight chisels do.

I was finding it quite awkward sharpening skewed chisels on the Tormek: mounting them in the square edge jig was awkward and the other jigs just didn't seem to suit this sort of chisel very well.  To solve that, I made a very simple to use 3D printed jig that seems to work really well.  I printed this about a year ago, but I've finally got round to publishing the model so I thought I'd post it here as well in case anyone's interested.

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The model is available here (along with more photos and details): https://www.printables.com/model/535539-tormek-skewed-chisel-sharpening-jig

I made this a while ago, but only just got round to making it available on-line.

Router plane blades can be a bit of a pain to sharpen.  I thought it would be a nice to be able to be able to sharpen them with the Tormek, but it didn't seem to be very straightforward.  One of the Tormek sharpening videos shows a router plane blade being sharpened but it's a very unusual shape one that looks a lot easier to sharpen than any of the ones I've got 

Anyway, it occurred to me that a 3D printer could be persuaded to make this job easier and hence:

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If anyone else is interested in this, the model can be downloaded from here: https://www.printables.com/model/332395-tormek-router-plane-sharpening-jig

There's also a jig for hand sharpening router plane blades available here: https://www.printables.com/model/535546-router-plane-blade-sharpening-jigs, but that's got nothing to do with Tormek