Thread: The Unicorn method

Originally Posted by RossM

I actually prefer longer videos like DWs. I despair at the ever decreasing attention span that the electronic age seems to be driving people to.

I meant it from a production perspective.

The video is RAM-PACKED with information. My hassle is the really juicy bits are interspersed with other info.

Nothing wrong with a conversational video (as Ian Hawthornes box making videos are long conversations), but this info seems like an idea that will change how sharpening is done WORLDWIDE FOREVER.

Hence the importance

Hi David,

I couldn't see a bright strip because the secondary bevel was bright off the stone and back 1-2mm or so - so the whole front end was bright.

Although a late thought was - I recalled now that I was using a loose wheel instead of a stitched wheel (on the other wheel, that I usually use with black fast-cutting paste). Do you think that could be making a difference? That might have meant I was actually mostly touching up the area behind the edge, as I was conscious of not jamming it in, but the fluffy loose bits might have been making contact a bit far back from the edge and preventing me from getting the effect.

I will have another crack.

Imagine that you are looking at a dull blade. The edge will show light, which indicates there is wear (the converse is that the absence of light shows it is sharp or, rather, that the face meets the back cleanly).

Now, after adding the nano bevel via stropping, this light returns. If it is not there, then there is no rounded nano edge. Too much of this and the edge is dubbed. Just enough and the edge remains sharp (or sharper).

Regards from Perth

Derek

Thanks for all the information here. It been really interesting and valuable.


I've been putting off buying a bench grinder but I think I may need to do so - and a buffing wheel!

Cheers

It is said there is a problem using the technique to do plane blades.

Would doubling the width of the buffer overcome this?

Hi David,

What's the method for touch ups? Straight back to the buffing wheel or back to the stones followed by the wheel?

Cheers
Zac.

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Originally Posted by Fergiz01

Hi David,

What's the method for touch ups? Straight back to the buffing wheel or back to the stones followed by the wheel?

Cheers
Zac.

Sent from my Nokia 4.2 using Tapatalk

if you see small damage occurring, then you can buff for a second or two again to try to improve the strength of the edge, but generally, you shouldn't need touch ups between sharpening.

Unless you have to grind, it's just 15 seconds or whatever it takes on a medium diamond hone and then hit the buffer again.

Originally Posted by woodPixel

It is said there is a problem using the technique to do plane blades.

Would doubling the width of the buffer overcome this?

There's a little narrower range for the amount and orientation of the buffing, but it will do plane blades OK.

Our experience on woodcentral (where some of the members are in clubs and they're pushing this whole thing at club members) is that most folks can take any chisel (Without all of my suppositions about ideal use) and stick it in a buffer and be better off the first time, but my guess with plane irons is that folks will need to stick with finding the right feel a week or two and then they'll have excellent plane irons.

I'd be surprised if most people make the effort to get the right feel for planes with their setup, but it's worth doing. Speed and type of wheel changes things, so there's no preset angle to tell anyone. As far as wider, I think the 1/2" wheels are ideal for everything. It's not so much the wheel width that's an issue, it's just nailing the right amount of buffing and not forgetting to work the back of an iron on a stone to keep geometry good.

Originally Posted by Fergiz01

Hi David,

What's the method for touch ups? Straight back to the buffing wheel or back to the stones followed by the wheel?

Cheers
Zac.

Sent from my Nokia 4.2 using Tapatalk

Zac, you will want to try this with knife, chisel and spokeshave blades ...

Take a sharp blade and test it. Then take this blade and hold the bevel in line to the circumference of wheel so that the wheel buffs the bevel. Try the edge again. I did this today with spokeshaves I was using, and the edges were sublime. This is not the Unicorn edge. This is just buffing an edge to get sharp.

Now try again. This time increase the buffing angle by 20 degrees, but very lightly and for about 2 seconds. This should leave a very sharp edge that will have a nano bevel (i.e. Unicorn). Remove the wire edge.

Regards from Perth

Derek

Thanks David and Derek,

I'm still waiting for my cloth wheel to arrive and I'm running through the work / sharpening scenarios in my head. I'm doing a bit of a reorganisation of my set up at the moment and the grinding and sharpening station is next.

Cheers,
Zac.

Sent from my Nokia 4.2 using Tapatalk

Originally Posted by Fergiz01

Thanks David and Derek,

I'm still waiting for my cloth wheel to arrive and I'm running through the work / sharpening scenarios in my head. I'm doing a bit of a reorganisation of my set up at the moment and the grinding and sharpening station is next.

Cheers,
Zac.

Sent from my Nokia 4.2 using Tapatalk

Have at it once the stuff gets there. Before then, no worries setting up too many scenarios. In general, this is easier than you'll expect it should be. There may be some learning curve to really get things ideal, but it's short and the result is otherworldly.

Originally Posted by Chris Parks

Derek, judging from the responses or lack of the word has not spread yet. ....

Originally Posted by derekcohen

Yeah Chris, I expected that at least there would be questions and a discussion. Is no one interested? Confused? Both?.......

I am one who saw the initial post and sat on it, not sure what to do.

My initial reaction was incredulity, disbelief ....... but the posters were Derek, Chris and DW, all with extremely high credibility.

My second, and continuing, reaction was puzzlement; how could something so simple and so close to traditional wheel buffing yield such superior results? And what if the primary bevel is not 20* - will it also work with 35* bevel on a mortice chisel?

Finally, do I go and buy a buffing wheel, or wait and listen while other Forumites experiment, test and refine the method further?

Hi Graeme

Here is a picture taken last evening ...



At the rear are two Fujikawa mortice chisels. I spent Sunday preparing the 6mm, which involved flattening the back (which was low at the bevel end) and then changing the bevel from 35- to 30 degrees. That was a lot of work as the steel is very hard - much harder than I expected. Even the "soft" iron was as hard as most tool steel. When it was done, I tested the edge by paring end grain Jacaranda (the softest wood to hand). It did okay but not as well as I hoped (compared to a bench chisel). I gave it a 2" lick on the buffing wheel, and the edge was transformed. Note that I was more interested in sharpness here and had hone to 13000 on a Sigma waterstone.

Yesterday (Monday) I did the 8mm mortice chisel. This was a Lot more work, with a 40 degree bevel! I did not have as much time by this stage, so stopped after a 600 diamond stone on the bevel (the back was polished to about 10000), and then used the buffer along with a nano (Unicorn) bevel. It simply reeled off shavings leaving a smooth, silky finish ....



I made new handles for my two gennous. The previous handles were too skinny for my taste, and these are chunkier. To shape them I used three spokeshaves, two LN (one with a hollow blade) and a Stanley #84. These were buffed on the wheel. The result absolutely transformed their performance into the effortless!

I also honed blades for the cutting gauges, which is an interesting discussion for another time, suffice to note that the edges are sharp.

The point is that none of these have a 20 degree primary bevel. The mortice chisels are 35 degrees. The spokeshaves are 30 degrees. The earlier post of the Marples chisels were 20 degrees, but the Stanley chisel was 25 degrees, as were the block planes I did.

Regards from Perth

Derek

p.s. I have probably mentioned this before, but it is worth repeating for the confused: I have used a Tormek leather buffing wheel for donkey years, and never really been happy with the results on anything, especially curved blades, such as gouges. The wheel on the Tormek is hard, covered in leather with little give. The stitched cloth buffing wheel is a different kettle of fish.

Derek - i noticed you purchased a second bench grinder for the buffer. I am about to purchase my first bench grinder and wonder if I can get by with one grinding wheel and the buffer (replacing the finer grit wheel). I am only sharpening plane blades and chisels at this stage.

Or would be best to have the two grinding wheels and put the buffer on a drill?

Thanks for any advice.