Thread: Zowada Website - double bevel info. updated

I've got a couple of questions. Tim's write-up says do traditional honing as you'd usually do. I took this to mean hone as normal to the point where you would then take the razor and shave with it. Then, whack some tape on the spine, increase the angle, and do some more finishing.

First, what happens to the edge created under traditional honing when the angle is increased? Do you create a small wire edge that breaks off?

Second, and maybe I'm not visualising this correctly, but I'm not getting how a steeper angle is any more effective at removing coarser grit cuts than polishing at the original angle

Can anyone help me out here?

James.

Originally Posted by Tim Zowada

I've just update the razor care and double bevel honing sections of my web site. I hope it makes a little more sense. Or, at least, is not totally confusing.

www.tzknives.com/razorcare.html

www.tzknives.com/twobevel.html

Thanks for your patience with my weird ideas.

Tim Z.

Tim thank you for contributing valuable information to our community it is greatly appreciated. Look forward to meeting you in Person Next Friday.

James,

The reason is because the number of strokes you hone depends on the AREA of the bevel you are working on.

The number of strokes goes up as a square of the dimensions, so if you double the width of the bevel, you can easily multiply by 4 the number of strokes needed.

By taping, you tip the razor up and are contacting a much smaller area of the bevel, which means the honing goes orders of magnitude faster.

The Clauss I just did has about a 3/64" wide bevel after I ground out the chips. But after taping, the the secondary bevel is less than 1/4 the width of the full bevel. I probably over-did the polishing with the 8K at 40 strokes. I believe it could have been accomplished with 1/2 that. Polishing out the scratch marks without taping would have hundreds and hundreds of strokes, I know, I've done it before.

That's why I said it is great for restorations where the bevel has gotten wider due to having to grind out big chips. It really speeds things up.

I lathered up the other side and shaved again with this razor. This time, no bleeders, no irritation--I just backed off on the pressure. You really need a very light touch with such a sharp razor.

I have always been fascinated with creating a straight line on the edge.

A while back, I tried creating that line by dragging the edge on the stone, point down, the blade perpendicular to the stone. It created an awesome straight line but of course, a totally dull blade.

Then I tried to hone carefully so that i *just* reached the point where the two bevels met again. My skill was not so good, and this never really worked.


However, now this secondary bevel thing gives me an idea.

If I get a razor close, then make a flat on the edge, it might be a lot easier to get the two sides of the bevel to meet with two layers of tape, i.e., creating the secondary bevel.

The next step would be to remove the tape and *carefully* hone the sides down till just *before* they meet. This would, theoretically, create the absolute minimum size secondary bevel. The idea would be to make this bevel smaller and smaller until it just disappears. It seems like this might create a better edge.

I don't want to try it with a restored razor with a wide bevel though. I need to do it with something already in good shape...maybe my filly.

Whaddya think, am I off in la-la land? Probably.

Paul

Ah, thanks toolarts! I generally tape all my spines anyway, which is maybe why I wasn't understanding that there was an issue.

James.

Originally Posted by sebell

Tim, did you use the factory finish on the UF to
give the edge that you photographed, or had you
lapped the stone previously? If so, how did you
lap it?

I've been curious

- Scott

Scott,

It was lapped so that the original factory marks were about 50% gone. I used 400 grit Silicon Carbide paper on a surface plate. I wish I had a DMT !

Tim Z.

Originally Posted by Tim Zowada

Garry,

I don't mean to be contrary, but that's not what those photos are. They show the regular honing bevel relative to the un-etched Damascus on the main grind of the razor.

You need at least 200x just to see the micro bevel we're talking about here. Taking good pictures is difficult due to the reflections and depth of field at the high magnification.

You can see some edge close-ups here:

http://www.tzknives.com/razoredges.html

The page is a comparison of stones and the finish they give to the cutting edge. There aren't any double bevel photos here either.

I'm doing some experimenting with the compound step. I'll be posting photos that show the Chromium Oxide finish on the double bevels someday...

I'll be bringing my microscope to Lynn's "shindig" for those who want to play.

Tim Z.

Oops .. thanks for clearing that up Tim

Garry

Originally Posted by Tim Zowada

Scott,

It was lapped so that the original factory marks were about 50% gone. I used 400 grit Silicon Carbide paper on a surface plate. I wish I had a DMT !

Tim Z.

I'll trade you my DMT 325 grit for a damascus blade

I have had many long conversations with our friends down at the Japan Woodworker (since my sailboat is 100 yds from their door).

They really push the sandpaper on flat granite or glass approach for plane irons and chisels--woodworking tools. I think others call it the "Scary Sharp" method.

The 325 DMT is nice, but it degrades. No matter what they say, they loose significant agressiveness over time.

Also, I still have concerns over the DMT's uniformity. It produces little scratch marks and BIG scratch marks.

My next restoration experiment will be sandpaper on glass.

Anyway, MUCHO thanks to Tim Zowada for this excellent string and the double bevel idea.

I just did a silver steel full wedge and created a secondary bevel that can only be seen at 100X, and the results are unbelieveable. I have *never* been able to get this thing to shave, and it is shaving nicely now.

Regards,

Paul Houtz

Tim,

Thanks for the info! Man this sure is enticing to try
out on one of my blades... except that I have just
one

- Scott