Thread: Time-effective alternatives in sharpening

Originally Posted by BobL

I recommend licking.

There are those who would say that's a good idea in my case, but it wouldn't stop my fingers from typing.

To get back to the original post, just a few points...

1. With acute bevel angles, the smaller the grind wheel the more the actual angle drops below the nominal angle set (see Lee's book on sharpening). So 6" wheels need adjusting for and produce a greater hollow in the bevel which in some cases is not desirable.

2. Speaking from experience of the Tormek T7 and a dry grinder (8", #46 3X wheel), the former is nice cos you can't blue the edge. Otherwise, if what's intended is a change of bevel angle or major regrind due to edge chip out, it's not especially fast. Expect to clean the wheel with the stone grader every 2-3 mins when working on something like a 1" chisel. Then if you want the fine grind (c. #1000) you have to regrade it. If you want to use the honing wheel, the chisel has to be remounted in the square edge jig. If you're going back to the std grit of 220 on the wet wheel for the next tool, it has to be regraded again. (All of this is an inducement to small batch methods of course).

And in due course you'll need to retrue the wheel.

3. The 3X dry grinder wheel works to the edge if you're patient. Otherwise, yes, just leave a micro-bevel for a whetstone and something coarser than #1000 would speed things up. (The greatest point of risk with a dry grinder is the corners when you're grinding to the cutting edge; there's less mass to act as a heat sink then. Dipping in water used not to be recommended because of micro-fractures in the edge; don't know what the gurus say these days).

HTH

BTW, Derek didn't like the friability of that wheel.

IMO it's a strength. The swarf ends up on the bench, along with a deal of AlOx particles. That's what's meant to happen. Better than the wheel glazing/clogging, by far.

Originally Posted by rsser

BTW, Derek didn't like the friability of that wheel.

IMO it's a strength. The swarf ends up on the bench, along with a deal of AlOx particles. That's what's meant to happen. Better than the wheel glazing/clogging, by far.

Hi Ern

Not always.

It's a strength when you want to keep down the heat. That is why the wheel was developed with such a friability.

However, it is hugely messy. The grit flies everywhere. Importantly, it flies into the air we breath.

I have been using this wheel for some years now. I also have a white 46 grit Norton wheel that is less friable, and this is the one I inevitably use. With a light touch I get the sae results as on the blue 3X wheel. For those who are starting out, with a heavy hand, the 3X wheel is excellent. Just wear breathing gear.

Regards from Perth

Derek

Yes, protecting your airways is important.

I haven't had much stuff floating around judging by the snot test and the wheel gets plenty of use.

It's a trade-off. The 3X wheel cuts HCS and HSS faster than any other alox wheel I've used (white, pink, ruby and BlueMax), clogs less and so needs dressing less often (at which point you really do need good PPE regardless of wheel composition).

Hi Ern

Are you using the 3X wheel for HSS or HCS?

For the average turner who only uses HSS, I cannot see the benefit. Speed is not critical. Neither is heat.

I am repeating myself when I say that 3X is of greatest benefit to the newby sharpening HCS, especially plane and bench chisel blades.

Regards from Perth

Derek

As posted Derek, both.

For HSS turning tool bevel reshaping, and I've been doing a bit of that for my students, it's excellent. It eats HSS, even the stuff with 10% vanadium.

The OP talked about 'time effective'. This wheel is IME as I don't care about the mess on the grinder bench.

And with HSS heat isn't critical; we can blue an edge without the temper being affected.

Thank you Ern and Derek for sharing your wisdom, as a result of which I have conducted some experiments, learning a lot.

I have sharpened plane irons and chisels for a few years now, to shaving-the-arm sharpness (my only criterion), freehand with chisels and a honing guide for plane irons.

My query involved saving time in sharpening. In answering this query, I am on track to much better sharpening, also faster.

I have spent time and $$$ on an enjoyable experiment. I talk about it here for the possible benefit of other learners.

Note: in order to save time and to avoid possible micro-cracking, from the outset I resolved to avoid quenching altogether.

BEVEL ‘CREEP’
All my sharpening had been done by reference to existing bevel angles. Chisels had been getting chipped too much.

In an effort to save time, I decided to standardize bevel angles: 25deg., 30deg. etc. In the process I discovered my bevel angles have been creeping lower because there has been no standard. A close-to-20deg. bevel angle, even on a paring chisel, is a good reason for chipping.

SHAPING
I bought both a slow-speed Creusen 150mm bench grinder and a Tormek and a second Veritas tool rest. Belt and braces, yes, but I had the money set aside.

I took the 40mm wheels off the Creusen and mounted a Norton 3X 19mm wheel and an Optigrind 20mm wheel, each with a Veritas tool rest; the rests share a Veritas grinding jig.

On advice from Derek I cambered the 3X wheel and wore a respirator when dressing the wheel. I suspect it may not be necessary to wear breathing protection when grinding with the 3X wheel but it certainly is when dressing the wheel; when grinding, coarse grains litter the bench; when dressing, masses of coarse grains litter the bench and a ‘smoke’ fills the air.

Cambering the wheel gives so much more control. The 3X wheel runs cool and the only time I burned the edge was this: if you want to reshape a fine bevel angle to a larger bevel angle and you push the edge onto the wheel (rather than starting at the shoulder) the edge is utterly unsupported and blues, but you are getting rid of that edge anyway and once the edge has another approx 0.20 mm on the wheel, it is pretty much impossible to burn any steel.

I contacted Optigrind and ascertained:

• Given the choice, they prefer a slower bench grinder
• The grit equivalent of their CBN wheel is 200.

I took the guards off the Optigrind end of the grinder (it is a steel wheel) so I can use the Tormak Angle Setter. For my first (and so far only) experiment last night I set at 25deg. for a Hock A2 Cryo iron.

UNBELIEVABLE. A light touch…fast and cool. Reshaped, and straight off the wheel of a slow-speed bench grinder, you can grasp the tool (edge to shoulder) between thumb and finger and feel virtually no heat.

Only time will tell how long this expensive wheel lasts.

HONING
I set the Veritas Mark II at a bit higher than 25deg; straight to a secondary bevel on 6000 and 8000 waterstones…. quick hone and arm-shaving sharp. The rest of the face, the primary bevel, remains at 200 grit coarseness…..does that matter? I can’t imagine how or why, but am happy to hear.

TORMEK
Was there any need to buy the Tormek? In a strict woodworking sense, and given my desire for speed, probably not, but I had other intentions: knives and scissors, plus the potential for woodturning tools, a project that is ahead of me..

I won’t go into knife sharpening here, but will say: the transition from linishing knives and scissors freehand to the Tormek is beautiful. The human arm and hand cannot consistently replicate a robot or jig; rounding happens.

The Tormek is a superb machine. I have shaped some irons and chisels but I don’t want to spend all that time. In due course I may end up using it a lot; it’s a privilege to have the choice.

ANGLES
There is a disconnect between the same angle set with the Tormek Angle Setter and the Veritas Mark II honing guide….too may variables here: they are approximations only; which one is measuring from edge to shoulder, which is measuring the more acute angle within the hollow?, etc. It doesn’t really matter: if a direct transfer from the Tormek or the Creusen to the honing guide looks like struggling to achieve a secondary bevel quickly, I do this:

On the Veritas Mark II set the secondary bevel setting at the first setting (3 o’clock) and do a quick hone on a 1000 grit stone; move to the second setting (6 o’clock) and hone at 6000/8000 (or whatever you wish) to create the micro bevel. Seems to work well and quickly.

Thanks to all who made positive and helpful suggestions; these have resulted in better and faster sharpening which means it’s less of a chore.


Any questions from other learners, please ask.


Mark

Thanks for the update Mark.