Morning, while watching an episode of Woodwright’s Shop a fellow who workins with hand tools in the Japanese tradition mentioned how when sharpening its important to avoid creating a wire edge, then breaking it off.
When I thought about what the gentleman said I began to see his point. If sharpness is the meeting of two flat planes at an angle, then creating a wire edge from honing etc., then breaking the edge off kind of defeats the purpose of honing the blade edge doesn’t it? The new cutting edge now has a ‘broken’, jagged edge.
I am not a sharpening guru. I was just curious if anyone has thought of this and if there are methods of eliminating the wire edge. Perhaps alternating strokes on the bevel side and then flat, back of the blade, to minimise the creation of a small wire that has to be broken off. Thanks for your consideration.
Ian
Edited 5/28/2008 7:18 am ET by Barrel
Replies
Barrel,
I always use the creation of a small burr or wire edge as an indication that I've gotten past the rounded-over (dull) portion of the edge. As you say, alternately working the bevel and flat side of the blade on fine stones eliminates the burr. I don't try to "break it off", so much as let it fall aside as the edge is polished.
Since the burr, however small, is a portion of blade that gets discarded, I try and make sure that it is small as possible; makes the blades last longer. For hobbiest workers this probably isn't an issue, but for someone using and sharpening blades every day, it becomes one. I've used up several block plane irons, and nearly as many smoothing plane irons over the past 35 yrs. Fewer as I've gotten less heavy-handed at grinding bevels.
Ray
Barrel,
After using Scary Sharp down to 2000 sandpaper, and really getting a bright bevel, there is still a bit of a wire left on the edge of the blade. I knock it off with a few quick passes of a bastard file, or sometimes I just hold it perpendicular to the floor and run it over the cement a few times. Either way, the stupid wire is gone!!!!!! Damn, I hate those things. :-)
Mel
Measure your output in smiles per board foot.
For shame, Mel! Aren't you concerned about your reputation on this Forum?Frosty"I sometimes think we consider the good fortune of the early bird and overlook the bad fortune of the early worm." FDR - 1922
Frosty,
Sometimes the humorous part of my brain takes over.
I do try to make it obvious when I am not being serious.
Was the comment about the bastard file too subtle?
Mel
PS posts on sharpening don't really get serious until they start talking about primary, secondary and tertiary bevels and a back bevel, and possibly a secondary backbevel. Every woodshop should have an electron microscope to check the sharpness of ones tools. Without one, you can never know just how sharp a tool is. I suppose you could use it and see if it works, but an electron microscope eliminates all doubts.Measure your output in smiles per board foot.
Subtle? "Subtle-Mel" is an oxymoron! Keep up the good work.By the way - are they going to use one of your bowls to repair the toilet on the space station?Frosty"I sometimes think we consider the good fortune of the early bird and overlook the bad fortune of the early worm." FDR - 1922
Frosty,
NASA does not have enough money to buy one of my bowls. :-)
MelMeasure your output in smiles per board foot.
Geez Mel,
You're talking about the primary and secondary back bevels and you completely forgot about the most important part of all--the fore bevel.
T.Z.
Thanks for the replies everyone. Derek, I have been performing the same ritual as yourself, removing the 'burr' after each progressive grit with a sideways motion, on the surface plate used to lap and polish the back of the iron. I use an old 1 micron lapping plate found in the back of the lab for this. Likewise I continue honing until a new wire edge is created on the next grit.Strangely enough, I do have access to an electron microscope at work, however, I have no idea how to operate the thing and would hate to explain why I was spending the tax payers dollars examining the edge of a plane or chisel blade. It would be interesting and perhaps informative to examine the wire edge produced through various methods of sharpening, then remove the wire edge using a couple of methods and finally examine the tool again to note any differences in the cutting edge.Maybe not, sound like a fair amount of work.Perhaps I'll go back to sandpaper... Thanks again folksIan
Ian,
would hate to explain why I was spending the tax payers dollars examining the edge of a plane or chisel blade
Not worry, I'm sure you won't be breaking any new ground. :-) Who knows mebbe you could get a grant for the analysis.
Regards,
Bob @ Kidderville Acres
A Woodworkers mind should be the sharpest tool in the shop!
Ian,
If you're a government employee, you work for the people. As one of the people for whom you work, I give you my permission to use the electron microscope to use on your blade edges so you can get an idea about what's going on.
Better that use than some of the others my money has been going for..
ZoltonIf you see a possum running around in here, kill it. It's not a pet. - Jackie Moon
Tony,
Making a fore bevel is just play. That is why they call it fore play.
MelMeasure your output in smiles per board foot.
Mel,
You're wearing your concrete floor un-necessarily. Use a pair of vice-grips (I like the ones for sheet metal work, with the big wide jaws) grab that wire edge with 'em and bend it back and forth 8 or 10 times, comes right off. Or you can take the blade to an anvil and using a 3# cross-pein, hammer it loose. Use a cold chisel (don't want to mess up the temper) to clean up any ragged parts. Be sure you are wearing safety gear for this , or at least your tool belt, and a flannel shirt.
Cheers,
Ray
Huh Ray? You guys that are just so darned fussy about getting a fine cutting edge. I just don't know. Slainte.Richard Jones Furniture
Richard,
"You guys that are just so darned fussy ..."
This, from a guy whose "fine stone" is a cinderblock.
Hah,
Ray
"This, from a guy whose "fine stone" is a cinderblock".
Yeah, but it's well worn, so it's ultra smooth.
I like to start the fine sharpening process with coarse gravel followed by a bit of nutty slack, and finish on the cinder block for that ultimate atom splitting edge. Slainte.Richard Jones Furniture
It's only "ultra smooth" 'cause you forgot to lubricate it with an adequate amount of woofle oil. Flush out the swarf and it'll start to cut once again.
Banzai!
Mike D
Ray,
If you alternately heat and cool the tip of the blade, the wire will just fall off. Propane and Ice. That's the ticket. Watch out. That Richard Jones character is going to steal some of your ideas. I think that is what "slainte" means. Actually, I am jealous of Richard. He has a sign off "word" which identifies him, much like the newscasters on TV "Good night, and good luck". or cowboys "Happy Trails to you.". I gotta get me one a them sign off words or phrases. I will work on it. So far, I am only coming up with
- may your wires be little ones.
- may your tenons fit like .... (naw, cant use that one)
- y'all hurry back, y'hea (naw, overused)
- "Kiss my grits" (naw, thate's been used)I gotta keep working on this. If you come up with a good one, let me know.
MelMeasure your output in smiles per board foot.
Mel,
How about this:
"Measure your output in smiles per board foot."
Catchy, huh? You have my permission to use it.
Ray
Ian,
Creating the wire edge, I think, is important both as a visual or tactile way to monitor progress and for ending up with a sharp edge. I remove the wire edge through stropping with a strop loaded with a fine abrasive. But then I'm into getting a sharp lasting edge. I'm not into producing mirrors and have no use for 6,000 or 8,000 grit anything when sharpening. The finest stone I use is a translucent hard Arkansas.
Hi Ian
The creation of a wire edge is the natural consequence of one side of the bevel. It is never "broken off" since, as you note, this produces a ragged edge.
When honing a blade, whether for a plane or a chisel, there are two ways to deal with a wire edge:
In the first method, the edge is honed through a succession of grits and the wire edge is removed at the end. The wire edge diminishes in size as the grits become finer such that, by the final polishing stone, it is small enough to remove without tearing.
In the second method (one that I prefer), the wire edge is removed at the end of each grit. This is completed on the polishing stone. It takes only a few seconds to do - I run the edge sideways along a 8000 or 12000 waterstone (my preferred sharpening medium). This avoids a to-and-fro bending of the wire edge, which can cause it to snap. In effect, this method will "wipe" the wire edge away.
Why do I prefer to remove the wire edge after each grit? Far from viewing the wire edge as an enermy, see it as a measurement. It will inform you whether the bevel has been honed/sharpened to the back of the blade. If one does not reach the back, then you cannot create a truly sharp edge. Remember, "sharpness is the meeting of two flat planes at an angle".
So the wire edge is a "friend", not an "enermy". There is no need to avoid it.
Regards from Perth
Derek
I have thought about the wire edge and its affect on the cutting edge and it would in theory seem to degrade the edge. Sometimes I get a wire edge and sometimes I don't, yet I can't tell any difference in the quality of the finished edge. When I do get a wire edge, it always shows up at the first honing on a coarse grit stone, after grinding, and usually falls of at that stage or on the next grit, so it has at least 4 and possibly 5 progressively finer grits to remove any problems caused by the wire edge. I do not alternate sides when honing; when I first get a tool, I lap the back flat and polish it up to 2000 grit paper, and then I only use the 2000 grit on that side followed by diamond paste, from then on.
Rob Millard
http://www.americanfederalperiod.com
Ian,
Creating the wire edge or burr is an indication that you are doing something right in your sharpening technique. As you work thru the finer grits the burr becomes progressively smaller and the last stage of proper sharpening is to remove the last remnants of this burr.
In the early stages of sharpening I don't like to work the back of an iron that I have spent considerable time working to a polish so I just turn the burr back toward the bevel by pulling it across a piece of mdf or a flat piece of hardwood. When I get to the final stages of sharpening then I work the bevel and the back with the finest grits of sharpening medium to remove the burr.
I use sandpaper on a granite surface plate so when I get to 1500 grit I just dry the paper off with a paper towel and rub some Tormek past on the paper and use this as a strop to remove the last remnants of the burr.
Ron Brese
http://www.breseplane.com
The technique I use is pretty much as Derek describes.
One thing I would emphasize: Once you've completed the initial one-time clean-up and polishing of the back of your blade, that side of the blade should never need to see anything coarser than your finest stone. So attempting to speed up the process of removing a large wire edge by running the back across a relatively coarse stone isn't necessary and creates more work in the long run.
And one thing I would add: In addition to the wire edge decreasing in size as you go to finer grits, different kinds of stones seem to create different kinds/amounts of wire edge. I find that the newer ceramic waterstones produce a wire edge that is big enough that you can tell that you've honed sufficiently, but is small enough that it's easy to remove.
-Steve
Morning, while watching an episode of Woodwright's Shop a fellow who workins with hand tools in the Japanese tradition mentioned how when sharpening its important to avoid creating a wire edge, then breaking it off.
I agree, but my thoughts are from watching my grandpa sharpen a straight razor...
I was just a child, but as I recall he 'stropped' the edge on a two surfaced leather strap (I think one side was not leather?) Not sure, Maybe linen cloth? Or a Canvas Fabric ? He would sharpen a bit, then onto the strap (Both sides).. Then back to the oil stone..
Seemed to go on for hours!
Will,
That was indeed what's called a barbers strop and was used as you observed. The canvas/fabric side was used to remove any minute filings left from honing on the stone and the leather was used to establish a keen edge. Some old timers used to add a bit of shaving cream/lather on the leather for a really smoooooooooth edge!
If you were to look at the edge of a straight razor under a microscope you would see very tiny teeth spaced across the very edge of the tool, not unlike a chisel or plane blade. These teeth are left from the stone and oftimes there are miniscule particles within the hollows of these teeth; thus the use of the canvas/fabic side of the strop to remove them.
I still have mine from days of yore (1967 when I went to barbers school) and still use it today albeit for another use - plane blades and chisels!
Regards,Bob @ Kidderville Acres
A Woodworkers mind should be the sharpest tool in the shop!
Bob,
Interesting stuff about the barber's strop! I used to shave with a straight razor, back when I was young and wanted to distinquish myself from the industrial complex that creates things like plastic disposable razors. Did it for a couple of years with moderate success, using a couple of folding razors I picked up at yard sales. Not both at the same time though...
I never knew the whys and wherefores about the canvas and leather strops though. I'm a bit unclear from your description as to which comes first. After using the honing stone, do you go first to the canvas in order to remove the small particles caught between the "teeth" of the blade - and then to the leather for final stropping?
You're a fount of knowledge..
Zolton
If you see a possum running around in here, kill it. It's not a pet. - Jackie Moon
Zolton,
You have it. I think mebbe my sharpening skills with razors has held me in good stead with woodworking tool sharpening too. I'm still weaning myself from scary sharp into oil stones but as the the honey do list is rather long it's a slow process.
I have managed to almost wean myself of jigs though.
Regards,Bob @ Kidderville Acres
A Woodworkers mind should be the sharpest tool in the shop!
Bob had it wired.
Stone weekly. Daily: In order. 1st prepare your wood for planing with a $200 Silver tip badger brush with custom bone handle swirled in a proper gents creme in a sterling cloche,whilst heating your nap with hot towels,then...Battle!!Again in order: Strop canvas, leather, neck, battle dressing, styptic...battle dressing.....battle dressing,
Safety razor. The process only adds about 25 to 40 minutes to your mornings ablutions-- depending on the bloodletting.If you want to see over the top bevel talk check out triple back bevels done with wire on the far side.-- .http://www.badgerandblade.com/Fettling an old Stanleys is for wimps. Try a Doubleduck :)Also a great examples of battle on U-Tube. search straight razor.Boiler
Edited 6/3/2008 10:55 am by boilerbay
Boiler,
Try a Doubleduck
Ahhh yes indeed.
Doubleduck razors were indeed some of the best straight razors for barbers back in the day. Then along came the insertable,disposable razor blades but the old timers would have nothing to do with them. They couldn't be sharpened and there was no gurantee that they were sharp out of the box. Hmmmmm, now doesn't that sound familiar!
As they pointed out the new fangled blades had very blunt sides where the metal meets the sharpened edge. Virtually all solid steel blades were rounded on the end so as to prevent the tip from catching on the customers skin and cutting them.
Whenever George (one of the instructors from barbers school in Boston) did a ballon shaving demonstration, he avoided these new fangled razors for that very reason.
Regards,
Bob @ Kidderville Acres
A Woodworkers mind should be the sharpest tool in the shop!
Here's a quote that is almost always apropos in every sharpening thread:
Some people have a practice of making a bushel of preparation to arrive at one gill of product - M.T. Richardson
Returns at the margin diminish very quickly for intricate sharpening protocols. In other words don't spend thirty minutes honing to get two more minutes of working time with an edge.
Edited 5/30/2008 8:59 am ET by TaunTonMacoute
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