Strop care and maintenance

[Andrew Pitonyak]

In a recently reopened older thread about strops, I saw this question, which was left unanswered:


One question I would like to add. How often do you recharge the strop? Every Time? When you see it turn black? When you haven't done it in a while?

And I started thinking about it and decided that I have no idea, so, I let Google be my guide. One bit of advice that I found said something that I think said "when it turns black, it is full of metal, so clean it and apply more compound". They were also talking about "strop oil".

Clearly, there is much that I do not know. If I strop using compound...



Do I oil the strop before adding compound?
What oil would I use?
Do I oil after compound?
How do you clean a strop?


To be clear, I am assuming a leather strop as opposed to say a piece of wood that has been charged with something.

[Jim Koepke]

1. Do I oil the strop before adding compound?

The most oil that gets on my strop is what is left on a blade after being wiped clean from the stones.


2. What oil would I use?
3. Do I oil after compound?

See answer to #1.


4. How do you clean a strop?

Mine are leather and have never been cleaned. Compound is added when it seems stropping isn't having the desired effect on a blade.

Note of clarification: my strops are cleaned of dust occasionally.

There may be some debate whether or not swarf left on a strop is helping or hindering the strop's work.

jtk

[Kevin Hampshire]

Well, Now I find out I’ll need to buy $400 a pint strop oil!

Okay, I don’t know how much strop oil actually costs, and I didn’t know I needed it.

I will have to follow this thread.

[Jim Matthews]

A strop should be wide enough for your widest iron (3" for me) and charged with jeweler's rouge, if anything.

Most important, it should be easy to locate and reach.

[bridger berdel]

I have 2 kinds of strops; for razors and for tools.

For razors i use hanging leather and canvas. I don't use that for tools, but some woodworkwrs do, so it's not really off topic. I have the leather very lightly charged with red jeweller's rouge. I charged it about 20 years ago and have cleaned it 3 or 4 times since with shaving soap.

For tools i use a scrap of wood charged with green chrome oxide. When it gets dirty i throw it away. If it's for convex, straight or straightish edges like chisels or planes i use a flat piece of wood. If it's for something concave like an incannel gouge i'll use a dowell or carve an appropriate shape in a scrap of wood.

[Andrew Pitonyak]

If it matters, I was reading about "strop oil" in a knife forum. It was the first I had ever heard of it. It was also the first I had ever heard someone say that I should "clean" a strop. I have little experience with it, so, I thought that I would ask.

[Jim Koepke]

Well, Now I find out I’ll need to buy $400 a pint strop oil!

Much cheaper to pick up a little elbow grease.

Better than a barrel of hard knocks!

jtk

[Tony Zaffuto]

I do not strop everything-sometimes a few licks on my hard arkansas, sometimes on my strop. Seems my vintage steel likes the strop, seems modern likes the hard arkansas. My strop is a piece of horse butt, bought from Tools for Working Wood, way more than a decade ago. I laminated the leather to a flat piece of cherry (just happened to be laying there when I was looking for something close to the 3" width of the leather). My strop is well worn in, and has been oiled with whatever I use on my stones! Sometime Marvel Mystery Oil ($3.00 for a quart at WallyWorld), or mineral oil or Norton honing oil. No other compound used.

[Jay Larson]

In a recently reopened older thread about strops, I saw this question, which was left unanswered:



And I started thinking about it and decided that I have no idea, so, I let Google be my guide. One bit of advice that I found said something that I think said "when it turns black, it is full of metal, so clean it and apply more compound". They were also talking about "strop oil".

Clearly, there is much that I do not know. If I strop using compound...



Do I oil the strop before adding compound?
What oil would I use?
Do I oil after compound?
How do you clean a strop?


To be clear, I am assuming a leather strop as opposed to say a piece of wood that has been charged with something.


Hey, people DO read my posts.

Thanks for bringing this back up, Andrew.

[Andrew Pitonyak]

Hey, people DO read my posts.

Thanks for bringing this back up, Andrew.

I was sad that it was not answered and I really wanted to know too!

[Pete Taran]

My only strop experience is with the strop on my Tormek, which is a leather coated wheel. I've noticed over time that the strop compound and abraded steel build up and it can get sort of glazed and doesn't seem to cut as well. Additionally, since the leather is under all that, applying more compound just gets smeared around.

As a result of this, I took a simple card scraper and applied it to the wheel while running. With proper technique, you can scrape all that off in just a few revolutions and get back to the leather again. Then recharge and it's like new. If your leather strop (motorized or not) gets that way, try scraping it off with a card scraper and reapplying the abrasive. Strops work best when there is some roughness to hold the abrasive media.

[Osvaldo Cristo]

I strop my blades more frequently than to use stones. Actually I stropped all my plane irons (all three of them!!) as well chisels (eleven) today morning.

I do not add any oil but probably some residual oil incorporate into the strop. I add green compound when it looks necessary. The results in the sharpness of my cut tools are great - I could not be happier.

For years I thought stropping was something for nerds and I confess I was very wrong: it makes difference for all my blades and is way easier to restore sharpness for a blade than the "full sharpening process" at most of the cases.

[William Fretwell]

Strop frequently in between sharpening. No oil just green compound, when black more green compound. When strop worn replace the leather. Must have 5 different size strops at any one time.

[Gary Ragatz]

Here's an article on strops from the place I got my sharpening kit: https://www.sharpeningsupplies.com/Understanding-Strops-W111C60.aspx

They don't make any recommendation for using oil on a mounted strop. They sell a "dressing" liquid for unmounted razor strops, but I think that has more to do with keeping the leather supple than cleaning or lubricating for sharpening.

[alan west]

1,2 and 3- I do not use oil.
4- I have never attempted to clean the black off a strop. I sharpen a lot and strop after the oil stones. My strops end up with cuts and gouges from mistakes. So I make a new one about every 3-6 months.

[Rob Luter]

Where do you all source your sticks of green compound? I picked up one from a local Harbor Freight and it's pretty much trash. It's like a big stick of chalk. It works OK once you can get it on the leather, but charging the leather is a tough trick.

I see Lee Valley has a 6oz bar and it has good reviews. Next time they do free shipping I may pick one up.

[Stewie Simpson]

Based on ease of application, a better option for hand strops is the Pure Chromium Oxide Paste. IMO


https://oi1009.photobucket.com/albums/af219/swagman001/pure%20chromium%20oxide%20paste/_DSC0202_zpsm5idgwfd.jpg (https://s1009.photobucket.com/user/swagman001/media/pure%20chromium%20oxide%20paste/_DSC0202_zpsm5idgwfd.jpg.html)

https://oi1009.photobucket.com/albums/af219/swagman001/new%20stropping%20block/_DSC0211_zpsnnpftuwb.jpg (http://s1009.photobucket.com/user/swagman001/media/new%20stropping%20block/_DSC0211_zpsnnpftuwb.jpg.html)

https://oi1009.photobucket.com/albums/af219/swagman001/new%20stropping%20block/_DSC0212_zps1wng0fyv.jpg (http://s1009.photobucket.com/user/swagman001/media/new%20stropping%20block/_DSC0212_zps1wng0fyv.jpg.html)

[Rob Luter]

Based on ease of application, a better option for hand strops is the Pure Chromium Oxide Paste. IMO


https://oi1009.photobucket.com/albums/af219/swagman001/pure%20chromium%20oxide%20paste/_DSC0202_zpsm5idgwfd.jpg (https://s1009.photobucket.com/user/swagman001/media/pure%20chromium%20oxide%20paste/_DSC0202_zpsm5idgwfd.jpg.html)

https://oi1009.photobucket.com/albums/af219/swagman001/new%20stropping%20block/_DSC0211_zpsnnpftuwb.jpg (http://s1009.photobucket.com/user/swagman001/media/new%20stropping%20block/_DSC0211_zpsnnpftuwb.jpg.html)

https://oi1009.photobucket.com/albums/af219/swagman001/new%20stropping%20block/_DSC0212_zps1wng0fyv.jpg (http://s1009.photobucket.com/user/swagman001/media/new%20stropping%20block/_DSC0212_zps1wng0fyv.jpg.html)

I guess I didn't know the paste was available. Thanks for the tip Stewie.

[Pete Taran]

Perhaps Stewart can set us straight, but I think that chromium oxide stick is just chromium oxide in a wax base. Heating some up in mineral spirits or whatever will dissolve the wax will get that brew which I agree will be much easier to apply than the crayon. Stewart, what do you use to dissolve it?

Pete

[Barney Markunas]

Heating up anything in mineral spirits is not for the faint of heart. I'd make sure you have a beefy fire extinguisher handy.

[Patrick McFate]

408932

While we're on the subject of strops, I am curious about the leather that you are using. I found some scraps of suede at my local hobby store and tried to make a strop out of that stuff, but the "fuzzy" side is veryusfuzzy, making for a very uneven, bumpy surface. Where might I get something more like the tooling leather that you're using here? And can it be gotten in small quantities?

Thanks in advance for helping a baby Neanderthal.

[Andrew Pitonyak]

Where do you all source your sticks of green compound? I picked up one from a local Harbor Freight and it's pretty much trash. It's like a big stick of chalk. It works OK once you can get it on the leather, but charging the leather is a tough trick.

I see Lee Valley has a 6oz bar and it has good reviews. Next time they do free shipping I may pick one up.

The Lee Valley bar has good reviews. The Formax Green Chrome Oxide Compound has an excellent reputation from what I can tell. Woodcraft sells two sizes of this bar. https://www.woodcraft.com/products/green-chrome-oxide-compound-6-oz The larger bar has a description on their web site, but in store, while reading the package, they appear to be the same https://www.woodcraft.com/products/micro-fine-honing-compound This is also available on Amazon for about $17 with prime delivery.

I think that Lee Valley sells the Formax compound, but I could be mistaken. I don't remember how I came to that conclusion. On multiple other forums, many people swore by (rather than at) Formax as the only green compound that they would use.

At one time, I spent time reading about the FlexCut Compound. I do not remember off hand, which has the finest average size. I belivee that the FlexCut compound has a good reputation, but I have never tried it on knives or chisels, but I do have two bars of it to try. https://www.amazon.com/Flexcut-Gold-Polishing-Compound-PW11/dp/B000ZRZQIO

Finally, many people like to use the Tormek PA-70 compound even on hand strops. This is a paste and a little goes a long way. Numerous places sell this, and here is an amazon link https://www.amazon.com/Compound-Tormek-Sharpening-Grinders-leather/dp/B00149DIBE

[Andrew Pitonyak]

Here's an article on strops from the place I got my sharpening kit: https://www.sharpeningsupplies.com/Understanding-Strops-W111C60.aspx

They don't make any recommendation for using oil on a mounted strop. They sell a "dressing" liquid for unmounted razor strops, but I think that has more to do with keeping the leather supple than cleaning or lubricating for sharpening.

Great link, thanks!

[Stewie Simpson]

Perhaps Stewart can set us straight, but I think that chromium oxide stick is just chromium oxide in a wax base. Heating some up in mineral spirits or whatever will dissolve the wax will get that brew which I agree will be much easier to apply than the crayon. Stewart, what do you use to dissolve it?

Pete

Pete; the process you describe never happened.

https://www.workshopheaven.com/chromium-oxide-paste.html

[Tony Zaffuto]

I find putting a bit of Marvel Mystery Oil on the leather does a fine job of disolving my stick of LV green compound on the leather.

[andy bessette]

...Where might I get something more like the tooling leather that you're using here?....

McMaster-Carr.
https://www.mcmaster.com/8706K58

[Andrew Pitonyak]

While we're on the subject of strops, I am curious about the leather that you are using. I found some scraps of suede at my local hobby store and tried to make a strop out of that stuff, but the "fuzzy" side is veryusfuzzy, making for a very uneven, bumpy surface. Where might I get something more like the tooling leather that you're using here? And can it be gotten in small quantities?

Thanks in advance for helping a baby Neanderthal.

I live near a tandy leather store (see https://www.tandyleather.com/en/)

I bought a large piece (about $50 ish, I don't really remember). Thicker is more expensive. The leather has a rough side and a smooth side. Note that you can also purchase smaller pieces.

As an example, see this:
https://www.tandyleather.com/en/category/tooling-shoulders-bends-bellies

I just cut off what I want to use. I told them what I wanted to do with it and I have some vegetable tanned (I think they called it) as opposed to some kind of chemical that they said could cause issues with my tools longer term (rust??).

[Jim Koepke]

Interesting the Tormek PA70 paste, on Amazon and ebay, lists this specification:


Abrasive Averages 3 Macrons

Anyone know how big a Macron might be?

The Chromium Oxide paste linked in Stewie's post has this in the specifications:


Chromium Oxide (Cr2O3 ) is a superfine, 0.3 micron, polycrystalline abrasive

Is the particle size really different by a factor of 10?

One of my green bars came from a lapidary shop. (think gem and mineral shop)

The other bar came with an oilstone purchase.

jtk

[Pete Taran]

In typical Amazon fashion, it's a typo. The paste has particles 3 microns in size. 3 microns is about 8000 grit.

https://www.tormek.com/uk/en/accessories/other-accessories/pa-70-honing-compound/

https://www.gessweincanada.com/category-s/11328.htm

[Jim Koepke]

In typical Amazon fashion, it's a typo. The paste has particles 3 microns in size. 3 microns is about 8000 grit.

https://www.tormek.com/uk/en/accessories/other-accessories/pa-70-honing-compound/

https://www.gessweincanada.com/category-s/11328.htm

Which begs the question of the paste Stewie linked, is it actually 0.3 micron? Could that be a numeric typo?

Okay, it looks like the Amazon and ebay listing may have two typos unless macron is a tenth of a micron. My Websters says a macron is a dash used over vowels to indicate a long sound.

Found this with a little searching:

408966

Thems be small particles.

jtk

[Pete Taran]

Jim,

There is no such unit as the macron, unless Emmanuel Macron decided to name one after himself. At 5'10", those would be some very large particles.

If .3 micron is real, that's about 80,000 grit which is indeed pretty fine.

For reference, here are the prefixes used in the metric system:
408988

Patiently waiting for some yoctometer sized polishing compound. Perhaps Stewart has a source?



Which begs the question of the paste Stewie linked, is it actually 0.3 micron? Could that be a numeric typo?

Okay, it looks like the Amazon and ebay listing may have two typos unless macron is a tenth of a micron. My Websters says a macron is a dash used over vowels to indicate a long sound.

Found this with a little searching:

408966

Thems be small particles.

jtk

[steven c newman]

Andrew: You have seen what I use as a strop. They are $9.95 at the borgs, sold as leather belts to hold nail bags. That is all my strop is, and I use the rough, inner face of the belt. H-F crayon for the green stick. K.I.S.S.....

[Jim Koepke]

There is no such unit as the macron, unless Emmanuel Macron decided to name one after himself. At 5'10", those would be some very large particles.

Thanks Pete, the initial typo made me laugh. At one time my occupation was in the printing trade. Typos often make me chuckle. In this ad, not only did they get the word wrong, it appears they also had the number misstated.

One of my favorite typos (improper word usage) was on a sign on a sidewalk in front of a computer shop in Berkeley, CA. It claimed they provided "On Side Service."

Let us know if you ever find some of that yoctometer polishing compound.

jtk

[Stewie Simpson]

Patiently waiting for some yoctometer sized polishing compound. Perhaps Stewart has a source?

Pete; why am I being targeted. ??

Stewie;

[Pete Taran]

Stewart,

"Tis merely a lighthearted jest. Considering an angstrom is 10^-10 which is what they measure atoms with, 10^-24 would be the micro fragments of atoms or smaller. I doubt anyone is going to make any abrasive that small in this universe.

Pete

[Stewie Simpson]

Pete; its all cool.

Did you notice I answered your previous question.


Perhaps Stewart can set us straight, but I think that chromium oxide stick is just chromium oxide in a wax base. Heating some up in mineral spirits or whatever will dissolve the wax will get that brew which I agree will be much easier to apply than the crayon. Stewart, what do you use to dissolve it?

Pete


Pete; the process you describe never happened.

https://www.workshopheaven.com/chrom...ide-paste.html (https://www.workshopheaven.com/chromium-oxide-paste.html)

[Pete Taran]

I did and thanks for the source. I may have to order some and try it with my Tormek(s).

[Michael Bulatowicz]

At one time, I spent time reading about the FlexCut Compound. I do not remember off hand, which has the finest average size. I belivee that the FlexCut compound has a good reputation, but I have never tried it on knives or chisels, but I do have two bars of it to try. https://www.amazon.com/Flexcut-Gold-Polishing-Compound-PW11/dp/B000ZRZQIO

I have both the Flexcut Gold and the green compound from the local Woodcraft (I presume it’s Formax, but I threw out the packaging right after I confirmed that it worked fine so I can't confirm that it is indeed Formax). In my experience using both, the Flexcut Gold cuts faster but doesn’t leave as fine a polish. For better or worse, it also tends to “crumble” off the surface of the strop more readily, keeping the coating thin without any extra effort on my part but requiring more frequent reapplication; the green compound is more gummy and doesn’t initially adhere as well to either my leather strop or my wooden strop unless I heat it up somehow and keep the coating thin (i.e. scrape off the old before adding new). Before it’s been heated, the green compound tends to “peel off” both the leather and wood and gather into clumps. This is particularly a problem in the colder months when my shop isn’t so warm. When reloading a stop with the green compound, I will often try to kill two birds with one stone by (further) polishing my scraper burnisher while using it to friction-heat the green compound and evenly load the strop. It only takes a minute or so of vigorous action to get the green compound to load properly, and at the same time I polish out any marks left on the burnisher from the last time(s) I used it to turn a hook. Once loaded in this fashion, the green compound adheres better than the Flexcut.

[Andrew Pitonyak]

I wonder how a hair dryer would work if you wanted to heat things.....

[Tony Zaffuto]

I wonder how a hair dryer would work if you wanted to heat things.....

For the third time in this thread, try some "Marvel Mystery Oil"! Put a few drops on you leather strop, then rub the compound on the strop: it will dissolve the stick into paste form. The oil is available for about $4.00 a quart at WallyWorl.

[Dave Zellers]

I wonder how a hair dryer would work if you wanted to heat things.....
Both a heat gun (hair dryer) and light oil will soften and dissolve the wax in a stick of honing compound and help to distribute it evenly.

When it's time to recharge the strop, I get good results if I heat the leather before applying the new compound. Probably very little difference from applying a few drops of oil.

[bridger berdel]

For the third time in this thread, try some "Marvel Mystery Oil"! Put a few drops on you leather strop, then rub the compound on the strop: it will dissolve the stick into paste form. The oil is available for about $4.00 a quart at WallyWorl.

Marvel mystery oil is pretty good stuff. I also use mineral oil from the pharmacy. Cheap and clean enough to eat. Literally.

[Jim Koepke]

Marvel mystery oil is pretty good stuff. I also use mineral oil from the pharmacy. Cheap and clean enough to eat. Literally.

Check in the home health care section of most large grocery stores and you will also find mineral oil. Often labeled for use as a lubricant/laxative. It is great on cutting boards and oilstones. Add some mineral spirits if you want to reduce the viscosity on the oilstones, not the cutting boards.

jtk

[Tony Zaffuto]

I've heard, years ago, from an oldtimer (his age at that time is now younger than what I now am), that viscosity on oilstones is gaged to coarseness of the stone: fine stone, use very lightweight oil. Coarse stones need thicker stuff. I'm now wondering what how a lubricant, such as Ballistol would work (safe to ingest).

For strops, with over charging with compound, we're just making up a stone, but with a resilient surface, that gives under the blade. My charging is very light, and not built up.

[Warren West]

If .3 micron is real, that's about 80,000 grit which is indeed pretty fine.


80 k grit is about 10 times finer than what is needed. Sharpen to 1200 - 1500 and go to a strop. The grit levels some sharpen to today is insane.

[Jim Koepke]

80 k grit is about 10 times finer than what is needed. Sharpen to 1200 - 1500 and go to a strop. The grit levels some sharpen to today is insane.

Tool sharpness is an addictive pursuit. For me the various levels of shaving arm hair are usually sharp enough. If my straight razors were regularly used, my face's comfort considerations might get me to take it up a notch into the realm of hanging hair tests for sharpness.

jtk

[Warren West]

Tool sharpness is an addictive pursuit. For me the various levels of shaving arm hair are usually sharp enough. If my straight razors were regularly used, my face's comfort considerations might get me to take it up a notch into the realm of hanging hair tests for sharpness.

jtk

Yup and with razors, sometimes a duller blade is better. Duller in razor terms is still very sharp, but I don't see anyone raving about the shaves they get off diamond stropping compound, but many use CrOx or Coticule and other naturals as finishers and love the shave they get. There is NO woodworking that can't be performed effectively coming off a soft Arkansas and a strop.

[Andrew Pitonyak]

YThere is NO woodworking that can't be performed effectively coming off a soft Arkansas and a strop.

On the other hand, there is a ton of woodworking that I am unable to do even if sharpened to a perfect edge!