The stropping myth and how to sharpen tools with leather

hi I'm James Hamilton from stumping UPS woodworking journal and there's so much misinformation out there about stropping your woodworking tools even I was confused for a long time to stropping make a tool sharper is it necessary for woodworkers well soft leather round over an edge why not use MDF instead what about charging straps with paste in this video I'll try to cut through the nonsense and answer those questions so you can get an edge you need with minimal expense and hassle this was my great-grandfather's razor and leather strap the strap used to hang from a post I remember how he used to pull the leather tight with one hand and Stroke the razor back and forth across its surface he'd do a few strokes on each side every time he shaved what was he doing I hear many people say that stropping was just intended to remove the wire edge that was left behind by the sharpening stone that's the last remnants of Steel that the stone pulled away from the edge and left loosely connected like a fine wire but my great-grandfather only occasionally used his razor on a stone I saw him use the stone all the time for his pocketknife and then he brushed the edge against the palm of his hand to remove any wire edge the strop had a more complex purpose and understanding that purpose is key to understanding how a strop can be valuable for woodworkers as well a straight razor is a bit different than a woodworking tool it has an edge so micro thin that the whiskers on your face can bend and mash it so it can actually become wavy the outer surface can also form microscopically shallow scratches and even find chips from the hair by stroking a razor's edge back and forth on a leather strop you are realigning the steel bending it back in place so it'll cut cleanly again you're also burnishing the edge actually moving the surface of the steel around to fill in some of those microscopic Nicks and scratches that may have formed and depending on the material you're using to strop you may also be abrading the steel wearing away some of those fine chips and scratches granted the edge of a chisel is not nearly as thin as the edge of a straight razor but a strop can still do those same three things it can bend and change the alignment of the steel it can burnish or move the steel around the surface and it can abrade the steel away to remove the flaws if we as woodworkers utilize these three capabilities properly we can get razor-sharp edges as quickly and cheaply as our ancestors did some modern woodworkers say you should just use plain old wood for strapping the old-timers head wood so why did they use leather because good quality vegetable tanned leather is unique it's much smoother than wood but it also contains natural silicates making it a very fine abrasive would contain silica as well but you need only rub your hand on a piece of nice leather to see the difference this is a piece of vegetable tanned hide that's typical of what many people prefer for strapping tools I think it may be horse hide or cowhide maybe buffalo hide one side has a rough surface the other has been made smooth and shiny by repeated compressing under smooth glass rollers before an edge got dull an old-timer would strop it on a shiny surface like this because it's just hard enough to bend and realign an edge just abrasive enough to wear off a tiny bit of steel and just smooth enough to burnish and polish what's left of course for that to be effective he had to keep his head nearly razor sharp at all times otherwise he needed a more aggressive strop like linen or he was going back to the stones today instead of using a more aggressive strop we can just flip it over and use the rougher surface which is ideal for applying abrasive pastes that are more aggressive than the leather itself but still ultra fine we'll talk more about pace a bit later but what makes leather uniquely useful as a strapping material is the rough side holds compound better than wood or MDF and the smooth side is just the right surface for the finest honing some folks say it's better to use MDF than leather because the surface of MDF is hard while leather is soft if you press a tool against soft material you can compress it and actually curl it up a bit against the edge you're trying to sharpen potentially dulling it in theory this can be true especially if you're using a very soft leather that compresses easily let's go back to the barbers strum he may pull it tight and there's some technique involved to avoid rolling over your edge completely but even if he's careful the leather belt is still going to deflect a bit as he's stroking it wrapping around the edge more than a stiff piece of leather on a nice flat surface would compress so how can a barber get an edge sharp enough to shave your face if he's dulling it with every stroke less because there's a fine line between blunting and edge and dulling it a sharp edge occurs where two planes meet to be perfectly sharp those two planes would have to just keep going on and on and tell the steel at the meeting point is just Adams thick how long do you think an edge that thing would last not at all on the other hand if those planes meet at a slightly thicker point the edge will be more durable I'm not talking about taking your edge and rounding it right over I'm just saying that the slight deflection of leather combined with just the light abrasiveness of honing compound is not enough to dull a tool more than its sharpen so that said if you have a really soft leather or you've really bear down on your tool you could have some problems and that's why some people do prefer to use MDF instead I've done my share of MDF honing I'm not saying it's wrong if it works for you but I find that the rough side of the leather holds compound better there are quite a few options out there when it comes to adding abrasive compounds to your straps there diamond paste but these seem a little bit pricy for me and as we'll discuss shortly strapping is really a good way to save money not spend more of it one thing I've used a lot of lately is abrasive sticks these are mixtures of minerals and wax or grease and many of them can be identified by their color black Emery is the most aggressive one it's grit sizes about 25 to 35 microns which is comparable to about an 800 grit diamond stone since I sharpen with a thousand grit diamond stone before I strap black Emery compound would be a step backwards for me the next finest is white Rouge which typically contains aluminum oxide and it's often about 8 to 15 microns in size or comparable to a 2,000 grit stone next comes brown Tripoli which is four to eight microns or four thousand grit and then red Rouge which is two to four microns or about eight thousand grit the green and gold sticks that are common these days are around one micron or smaller which is comparable to ten thousand or finer grit I say sometimes because you never know for sure manufacturers don't always tell you what's in their compounds I can tell you this if it cuts really fast it probably contains some coarser particles in it a good example is this white paste trend doesn't say what's in it they don't say what the grit size is all I know is it removes steel really quickly as you can see by how a single stroke turns the paste dark with fine metal shavings but it leaves a super fine edge I've also heard of folks using Auto Body pastes and rubbing compounds so what should you use you have to find a balance between something that's fast enough and fine enough for your tastes I wouldn't go coarser than about 5,000 grit so that would encompass that red green or gold compound or the paste like the trend stuff that I use that is unless you're going to use multiple straps with progressively finer pastes we live in a world with a lot of sharpening options you can buy ceramic water stones with grits and the tens of thousands why would you want to use a leather strop because it will do the job with less hassle and less money a ten thousand grit water stone will cost you over a hundred bucks you have to maintain it to keep it from dishing out as you use it it can make a mess sometimes and eventually is going to wear away on you a chunk of leather like this will cost you a few bucks depending on where you get it the paste will cost you a bit more but it will last for years there's no maintenance no mess so here's my hand sharpen process if I have a really beat-up edge I'll grind a new bevel with a power tool like a grinder then I sharpen it with a thousand grit diamond stone which also requires zero maintenance I do own a five thousand grit ceramic stone paid a couple hundred dollars for it some time back but I don't need it if I'm strapping I can go right from the diamond stone a strop for final honing sometimes I take a few strokes with a coarse paste like that Brown Tripoli then I use another strop with a fine paste and I finish up with a few strokes on the clean shiny side of the straw it's just like working through the grits of sandpaper or water stones except I only need to invest in a single stone in fact if you want to keep it really simple use one stone and one strop with one paste on the rough side and no paste on the shiny side after that the key is just keeping your edge honed return frequently to the strop and you'll have to use the stone less and the grinder hardly at all that's fast easy and cheap I'll put links below this video to the leather I use if you need some and to the pace that's my favorite and diamond plates if you need those as well so check them out if you sharpen your tools by hand do yourself a favor try one of trends' Diamond stones you can start with the card but before long you'll want a full Bend stone because these things cut fast they stay perfectly flat you can go from stone to strop to wood and be back to work in under a minute I'll link to my favorites in the notes below this video wait don't go yet if you're new here please subscribe and remember to ring the bell I would really appreciate that give us a thumbs up or better yet leave us a comment I always read them and be sure to check out the latest issue of stumpy nubs of woodworking journal it's always packed with tips tricks and tutorials designed to make you a better woodworker

Channel: Stumpy Nubs

Views: 255,477

Rating: 4.9489918 out of 5

Keywords: woodworking, stumpy nubs, tips, workbench, table saw, scroll saw, drill press, quick tip, band saw, bandsaw, lumber, hack, hand plane, sharpening, tormek, worksharp, diamond stone, water stone, wood turning, bowls, lathe

Id: Gg2w_MobIW4

Length: 10min 16sec (616 seconds)

Published: Tue Jun 25 2019

Reddit Comments

[u/FerricInsanity]

Didn't get past 2 minutes in, this guy himself spreads misinformation. I suspected so as he did the same in his video on diamond sharpening stones.

A strop is nothing else in principle that a sharpening stone, abrasive media and something that holds abrasive media. Sometimes stones are hard bond/ ceramic meaning the abrasive is attached to itself but the principle doesn't change.

Putting an abradive on leather or other soft media makes the abradive particles embed themselves in said media and effectively making it finer since only part of it sticks up and can be pushed in further. You can actually test this yourself, test the same compound on leather and wood, the wood strop will cut more aggressively since the oarticles aren't embedded as deep and can't be pushed down as much. So a strop is basicly just an extremely fine sandpaper. Sharpen your knife properly, cut off burrs on your stone and use a strop to refine an established and clean edge.

A strop won't "burnish" or effectively realign your edge, it'll polish it. That's all. If you put enough pressure on a strop to realign steel, you're very likely using enough pressure to round your apex and you're missing the point ar this stage.

Listen to people who actually know what they'ee talking about. Cliff Stamp, Michael Christy, Big Brown Bear, etc.