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View Full Version : Passing Along a Great Tip - Stropping!!



Mark Roderick
06-05-2009, 8:58 AM
A couple of months ago, deep in the obscurity of a long thread about something else, Derek Cohen suggested that if you stropped a chisel or plane iron frequently, you could postpone or entirely avoid sharpening on a stone.

Well, I've been doing that ever since, and the results are remarkable. I don't think I'll ever sharpen a chisel again, unless it falls on the concrete floor. And sharpening of plane irons will be much less frequent, saving lots of time and metal. I've been cutting and chopping dovetails and flattening boards with my planes and if I strop frequently I find that sharpening is really unnecessary. Plus, stopping for minute to strop an edge is a pleasant break.

Anyway, this tip of Derek's seems so important I wanted to pass it along to those who might have missed it.

Thomas Pender
06-05-2009, 9:18 AM
What you say is consistent with the article in the most recent FWW. However and here is the question - where can you get a good strop? And I know this sounds dumb, but while I know you can do it with a chisel, how can you do it on a plane blade without taking the blade out and readjusting, etc.? Figure you cannot, but it is a tad messy using waterstones all the time and this seems like a good suggestion - if it works on chisels alone that would be great.:D

Thank you.

Danny Thompson
06-05-2009, 9:21 AM
When you say "frequently?"

Richard Dooling
06-05-2009, 9:23 AM
Thomas beat me to the punch but I'll add to the question.

What compound - green honing compound?
What are the differences between backers? Hard vs soft leather. MDF. Granite stone.

I believe that Derek uses the horse butt leather which I imagine is quite hard.

Matt Benton
06-05-2009, 9:49 AM
This is particularly timely for me, as I was planning to buy a Tormek in the next few days.

I'd be happy to do rough work on a stone if I can use a strop only for final sharpening/maintenance.

I'm assuming horse butt leather on granite would be the most preferable way to go?

harry strasil
06-05-2009, 9:52 AM
My Strop is just a piece of leather, an old belt or shoe leather will work, after sharpening I strop on the rough side, then turn over to the smooth side which has brown jewelers rouge on it, and when done the chisels go back in their little leather boot, same with my hand saws, they get the wooden edge guard put back on after use.

Joe Denney
06-05-2009, 10:02 AM
I strop frequently (kinda sounds dirty! :D) when I'm turning, and I very rarely have to sharpen my turning tools. I got my strop and the green stropping compound from Tools for Working Wood. Not sure about posting links to vendor sites, but you can google it and find it. Looking at about $30.00 or so for the horse butt strop and the compound.

Hope this helps.

Joe

Derek Cohen
06-05-2009, 10:11 AM
Thanks Mark for the vote of confidence. :)

Here is an article I wrote several months ago about stropping ..

http://www.inthewoodshop.com/WoodworkTechniques/Stroppingwithgreenrougeversesdiamondpaste.html

Hope it helps.

Regards from Perth

Derek

Barry Rowland
06-05-2009, 10:17 AM
I have the T-7 and the stropping wheel does and excellent job keeping a my chisels and plane blades razor sharp. I only go to the stone, other than initial grinding and honing, if I have managed to put chips on the blade edge some how.

Much more economical to use a strop if you don't want or have a T-7....

David Keller NC
06-05-2009, 10:32 AM
What you say is consistent with the article in the most recent FWW. However and here is the question - where can you get a good strop? And I know this sounds dumb, but while I know you can do it with a chisel, how can you do it on a plane blade without taking the blade out and readjusting, etc.? Figure you cannot, but it is a tad messy using waterstones all the time and this seems like a good suggestion - if it works on chisels alone that would be great.:D

Thank you.

Thomas - this is an age-old technique, and is absolutely typical for carvers - I've never met a carver that didn't strop his tools. Honing on stones (only) seems largely confined to the hand-tool woodworking community that doesn't do the carving thing.

As to where to get a strop, you can of course buy a commercial one from TFFW, and a few other sources. If you want to make one yourself, see if your town has a Tandy Leather store (most big cities do). Most of these stores have a "scrap bin" of bargain leather made of horse or cow hide. One can usually get fairly large pieces that will not be useful to an upholsterer or leather artist for very little.

As far as compound goes, there are lots of different ones on the market, and all will work very well. One source is a carton of "rottenstone", which is ground limestone used for rubbing out finishes in the french polish method. It works exceedingly well for stropping blades, as does the white goo that Tormek sells, yellowstone (generally sold at carving outlets), diamond paste, and even nothing at all.

From the staind point of plane blades, stropping will certainly work - I do it all the time in my shop. If the chip-breaker is set fairly far back from the edge (say 1/16" or so), you can strop the edge without dissembling iron/chip breaker. One simply gives the iron 4-5 strokes on the bevel, then flips it over and carefully runs the back of the edge flat on the leather once. Presto - instant surgical sharpness restored.

For a substrate, it's important to keep the leather flat. While you can strop a double-bevel knife blade on a loose strop (think barber's strops), keeping the leather flat when stroping a single-bevel tool is necessary to avoid rounding the bevel. In my case, I prefer that the leather be glued down to a stable wood scrap (mahogany in my shop, other stable woods, preferably quartersawn, will work as well).

Dominic Greco
06-05-2009, 10:45 AM
What you say is consistent with the article in the most recent FWW. However and here is the question - where can you get a good strop? And I know this sounds dumb, but while I know you can do it with a chisel, how can you do it on a plane blade without taking the blade out and readjusting, etc.? Figure you cannot, but it is a tad messy using waterstones all the time and this seems like a good suggestion - if it works on chisels alone that would be great.:D

Thank you.

Tom,
I use a piece of 3/4" MDF that was charged first with a drop or two of mineral oil. Then I drew a couple of lines with the green Veritas Honing Compound "crayon". Then I just ran the bevel of the iron over it a couple time. I could see and feel the wire edge forming and disappearing. And talk about an EDGE!!! I'd say "scary sharp" but that's over used. How about "Atom Splitting Sharp"? :D Yeah, it works that well!

The MDF is nice and flat and I never noticed it dubbing over the edges of my plane irons or chisels. Since I started using this technique, I find myself honing" less and less, and "stropping" much more.

Don C Peterson
06-05-2009, 10:52 AM
As for where to get a strop, just about any piece of smooth leather will work. I don't bother to glue the strop down to a piece of wood, my bench makes a great flat surface... plus if you glue it down you can't use both sides.

I hadn't thought of using rottenstone as a compound, but that makes sense. I typically use the green compound sold by toolsforworkingwood.com I bought one stick a couple of years ago and it will probably last at least 5 more years.

Julian Nicks
06-05-2009, 10:52 AM
I use a method similiar to Dominic. The difference is that I cut a 6" disc out of it and mount it in the low speed grinder and charge the side with the compound. It only takes a few seconds on both sides to bring the edge back, and I am back working. I have been doing this method for over a year, and have only been back to the scary sharp system after dropping a chisel on the concrete floor. It's so nice being able to not have to worry about the mindless task of sharpening through the grits.

Robert Rozaieski
06-05-2009, 10:55 AM
Stropping is a great method for keeping a sharp edge longer. You will still need to hit the stones at some point but the stropping extends the time in between stone honing. I keep my strop righ on my bench when I'm working and stop and strop very frequently while I'm working. Just a few swipes to renew the edge and right back to work. It becomes an automatic part of the process of working after awhile and you don't even have to think about it. You just instinctively stop, strop and them get back to work.

Russ Massery
06-05-2009, 11:04 AM
Does it matter? I'm getting ready to make a strop.

Derek Cohen
06-05-2009, 11:28 AM
Which side of the leather?

It does not matter. I have used both rough and smooth sides, and they work the same. In fact the rough side becomes smooth after a while, so ...

Leather does have a grain, just like wood, and you want to strop with the grain. It is a bit like running your hand against the growth on a cheek before shaving.

Hard leather is preferred by a mile to soft leather. Hard leather resists dubbing better. So does gluing the leather to a hard, flat surface.

I have experimented with hardwood and MDF (used the latter for afew years). They are not as good (for me) as leather. Leather holds rouge better, and just feels better in use.

I have also used power strops. I have a Tormek, and the wheel is good. Not as good as the (chamois) leather disk I make for my belt sander/disk sander combo. The latter is amazing ... but hand stropping is less hassle.

Regards from Perth

Derek

Marco Cecala
06-05-2009, 11:29 AM
I got the dubious honor of being a student for a trip to the sharpening doctor for Fine Woodworking. (It will appear in the August issue) 2 of us got to spend 2 days with Gary Rogowski at his shop. He tried many things, but ended up with a piece of leather, using the split side (rough) and Herb's yellowstone honing compound, available from Craftsman supply.

Dave Anderson NH
06-05-2009, 12:34 PM
I have various strops in the shop. I have the Betz carvers strop of rough out leather and it has been charged with Yellowstone for 20 years. I'm still on the original cake of the stuff, a little goes a long ways.

I also have have a set of maple plywood strops charged with diamond compound in 7, 3, and 1 micron grits. These work well too. I had made my original set out of MDF and finally replaced them with the maple ply on Garrett Hack's recommendation. In my experience both the MDF and the maple ply work just fine with little or no difference between them.

Russ Massery
06-05-2009, 12:35 PM
Derek, Thanks again! You and your website have been a big help with my hand tool endeavor.

Marco, I just read the article just last night. You lucky dog.:D

george wilson
06-05-2009, 4:33 PM
Most people use the suede side. I like to use the hair,or smooth side. A little Simichrome works fine for an abrasive. it gets finer as it is used,leaving a dark gray surface on the leather,which is very fine particles of steel. Just let the Simichrome wear ever finer. Any fine compound will work. I have found that stropping while the Simichrome is still wet feels like you aren't accomplishing anything,but really makes an extremely sharp edge.

Stropping won't make an edge last forever,but you can strop several times. Eventually,the edge will become too rounded over by the stropping,and you will have to hone a new acute angle,and start stropping again.


I DO NOT recommend this,but I heard about a Mexican wood carver who jammed his carving tools into a bag of sand several times to keep them sharp!! I do not imagine that produced a truly sharp edge,though. Maybe enough to carve pine.

Derek Cohen
06-05-2009, 10:43 PM
Thanks George.

And here is another method to try ...

About a month ago mention was made (on another forum) of using diamond paste on paper - ordinary copy paper. Of course I had to give it a go. Just curious.

I placed a strip of white copy paper on a glass plate, sprinkled with a little baby oil (mineral oil plus scent), and then mixed in a dab of .5 oil-based diamond paste.

And it worked very well ... to increase the sharpness of the edge. Just too messy for my liking, however. It may be less so with a non-oil based mix.

Regards from Perth

Derek

Jeff Willard
06-05-2009, 11:29 PM
I DO NOT recommend this,but I heard about a Mexican wood carver who jammed his carving tools into a bag of sand several times to keep them sharp!! I do not imagine that produced a truly sharp edge,though. Maybe enough to carve pine.

I remember reading something similar, years ago. But the story I heard was the carver kept jamming the gouge into a small pot full of a waxy substance, that obviously was charged with some sort of abrasive.

Tim Put
06-06-2009, 12:07 AM
Sounds a lot like sewing needle sharpeners.

Mark Roderick
06-08-2009, 11:44 AM
Others know a heck of a lot more than I do, but here's what I do:

My "strop" is just a piece of MDF, about four inches wide by a foot long. I charged it with the green compound and voila. It seems to me the only important thing is that it's flat.

For chisels, I stropped the blade after cutting the dovetails on one end of one board (I cut away most of the waste with a bandsaw first). Just 30 seconds on the MDF and I'm back to the dovetails.

Yesterday I was using a block plane to clean up the dovetails after the box was joined together. It's hard wood (maple) and there was a fair amount of hardened glue. I stropped the block plane blade after cleaning up each side of each corner, and there was no visible deterioration in the cutting from beginning to end.

Thanks again, Derek.

Griph0n Brown
06-08-2009, 2:03 PM
I sharpen with a veritas jig and waterstones to get a 25 deg. bevel (leaves a flat full bevel) and 30 deg. micro bevel.

When freehand stropping on mdf with lee valley green cmpd does it just hit the large 25 deg face and miss the microbevel? (seems so when I look at the mirror polished larger face, the microbevel looks duller or darker)

Would hard leather hit the microbevel better?
Would it polish slightly cambered plane blades better?

Thanks

Jim Koepke
06-08-2009, 2:31 PM
I sharpen with a veritas jig and waterstones to get a 25 deg. bevel (leaves a flat full bevel) and 30 deg. micro bevel.

When freehand stropping on mdf with lee valley green cmpd does it just hit the large 25 deg face and miss the microbevel? (seems so when I look at the mirror polished larger face, the microbevel looks duller or darker)

Would hard leather hit the microbevel better?
Would it polish slightly cambered plane blades better?

Thanks

What is being hit or missed is dependent on the angle at which you hold the blade.

jim

Derek Cohen
06-08-2009, 8:16 PM
When freehand stropping on mdf with lee valley green cmpd does it just hit the large 25 deg face and miss the microbevel? (seems so when I look at the mirror polished larger face, the microbevel looks duller or darker)

Hi Griphon

That is precisely why I wrote this piece ..

http://finewoodworking.taunton.com/item/8521/a-sharpening-strategy-beyond-a-sharp-edge

I could have called it "Sharpening for the Big Picture" :)

Regards from Perth

Derek

Mark Kosmowski
06-08-2009, 8:48 PM
Making a stropping board has been on my list for some time. I already have a four rouge kit by Craftsman. Will one of these sticks be useable or should I invest in a different abrasive?

As far as hard or soft leather, what exactly do you mean? When I hear hard leather I think rawhide and maybe a suede could be the soft leather? This leaves a lot in between though. I already have on hand a bunch of vegetable tanned cowhide that I was planning to use - either 1/4" or 1/2" thickness depending on the size and flatness of my scraps.

Thanks!

Bill Keehn
06-08-2009, 8:48 PM
I DO NOT recommend this,but I heard about a Mexican wood carver who jammed his carving tools into a bag of sand several times to keep them sharp!! I do not imagine that produced a truly sharp edge,though. Maybe enough to carve pine.

This doesn't sound strange to me at all. When I was little my grandmother used to keep a bucket of sand and motor oil in the shed. She would shove her gardening spade in it a few times after she was done with it, to keep it clean, oiled, and supposedly sharp.

Still, I don't think I'll be trying that on my carving tools :).

Griph0n Brown
06-09-2009, 6:57 PM
That was exactly what I needed Derek.

Thanks

(but now I need, (want?), a grinder.... crap)

Mark Roderick
06-10-2009, 10:55 AM
If you use a jig to sharpen on a stone, just use the same jig on the MDF, at the 30 degree angle. If your main bevel on the blade is 25 degrees, you're not going to be able to freehand the 30 microbevel.

Chris Padilla
06-10-2009, 10:59 AM
That was exactly what I needed Derek.

Thanks

(but now I need, (want?), a grinder.... crap)

Woodcraft almost always has a good deal on their slow-speed grinders and right now, they have free shipping....

Try this code: 63009 for $10 off a $20 order...it may work along with the free shipping...it did for me. :)

Kevin Hartnett
06-10-2009, 2:57 PM
I know a lot of you won't believe this, but I have a small pocket knife I always carry and I seldom have to sharpen it because I always strop it after just about every use. Why do I carry a strop around with me all the time you ask!? Well, I don't. I use the palm of my hand -- carefully.

What's a strop after all but a piece of animal hide. I even give my small chisels a quick strop on the plam of my hand every so often during use and it makes a difference. I learned this trick from an old fisherman who stropped his filet knife on the palm of his hand and always had the keenest edge.

Just be careful and strop in the right direction!!!

Kevin H.

Cliff Rohrabacher
06-10-2009, 3:30 PM
Does it matter? I'm getting ready to make a strop.

Well now, that raises an interesting question and a point that deserves making.


Abrasive Compound Stropping on leather wood etc., is a great way to get a finely sharpened edge. However, one might be well to bear in mind that the edge resembles more of meat cleaver grind. A real meat cleaver is thick and the grind is not concave ( or hollow) but rather Convex. The point in the cleaver being to heave things apart with the force of the blow. This is dramatically different from Chinese cleavers which are used like knives. and often sharpened on only one side.

Stropping creates a convex edge geometry (albeit on a nearly microscopic scale). When that little bulbous edge is tiny it works great. When it's larger after lots of stropping it becomes an issue you gotta grind away

The softer the leather ( or wood) and the more aggressive the abrasive used the more readily that convex edge will develop. Think of what's happening on the micro scale. The metal pushes into the strop which yields in a round-ish way which eventually becomes the geometry imparted to the edge. The softer the stropping material the mor pronounced the bulbous curve.


I should think that if you went with a piece of plate class (buy cheap cast offs and scrap from your local glass house) and a bit of diamond compound you'd get the same result but with no deviation from a straight line edge.

Of course at the scale most people are going to experience there is no real down side to stropping on a soft substrate. But over time without grinding on a hard surface it can build up.

As to which side of the leather to use: The hard shiny side.
The soft fibrous side will round the edge over faster.

Of course this all takes on a dramatically different element if there is no abrasive in the strop. as in the old school barber's strop. Those guys almost never went to the stones but, the blades were thin, thin, thin.

John Schreiber
06-10-2009, 3:55 PM
. . . I use the palm of my hand -- carefully. . . .
When carving with a knife, I often do the same on my pant leg. Like you said -- carefully.

Chris Padilla
06-10-2009, 4:26 PM
Hmmm, brings all new meaning to "hand stropping"!!!

george wilson
06-12-2009, 10:29 AM
It has been said that the palm of the hand is the ultimate strop. I wear a 1/2" wide belt made of English harness leather. The Harness shop (now closed) made it for me. I sometimes strop on the backside of it without abrasive for a touch up.

Even a sheet of paper will work if you keep at it long enough. When I was a kid with no money I did that.

harry strasil
06-12-2009, 1:09 PM
I remember on Okinawa, the native barbers sharpening their straight razors and then stropping, and whenever they started shaving me, they would strop on their hands. I had a really tough (hog bristle) beard and very tender skin then, and they would pinch up the skin the second time around and somehow shave my beard under the skin, I didn't need to shave for 2 days and normally I had to shave twice a day.

In boot camp that was real problem, and the jerk Company Commander had them dry shave me after inspection, they cut me up so bad I couldn't shave for almost 2 weeks and that really ticked him off even more, he tried to punish me for not shaving, till one of the Doctors came and had a nice chat with him.