My take on the LV chromium oxide compound

[Patrick Chase]

Hi Pat; some of the diamond pastes and honing sprays available on the market are down to 0.5, 1, and 2.5 micron in sizing. http://www.bestsharpeningstones.com/...mond-Spray.htm

Stewie;

Norton goes down to 0.25, PSI goes to 0.1, and others go even lower, particularly if you include CBN.

I have both 0.25 and 0.1, though I almost never use the latter because I've found it to be more hassle than it's worth. Probably the biggest hassle is that you'll end up polishing one or two spots on your blade unless you either use a flexible backing or your 0.1 um plate *exactly* matches the flatness profile of your next-higher plate. I mostly got it out of curiosity. For most things I stop at 0.5, and even that is probably overkill with a tightly-graded (low max grit size) paste.

[Luke Dupont]

Interesting discussion.

One thing: I notice that people are always pointing specifically to the LV compound in these discussions. Do you have any experience with other brands / find any noticeable variance?

I still am quite fond of the green compound because I feel it is one of the most cost effective, and easiest ways to get a very fine edge even if you finish on a fairly coarse stone, though. Even a 1200 grit diamond plate, or an India, when followed by a strop loaded with this compound will produce a pretty decent edge. If you use plain leather instead, you won't even be able to remove a burr often times at these grits, much less refine the edge. For this reason I used to doubt the effectiveness of bare leather, but since I've acquired some finer stones I'm beginning to be of the same impression as you.

Lately, since I have finer stones now, I've been experimenting with plain leather strops without compound, and I've been impressed with the kind of edge I'm able to produce. Ending on my Washita, I'm able to get a *much* finer edge than I would have expected just by going to plain leather. Same is true for my hard and translucent arks, though the difference (extent to which I'm able to refine the edge from its starting point) is less remarkable than it is with my Washita. My synthetics and waterstone don't seem to respond as well to an unloaded strop at the same "ballpark" grit. Mind you, the finest waterstone I have is only 2400 grit, but that should be finer than my Washita in theory. However, if I sharpen and strop on bare leather and compare the two, I'll get a significantly finer edge off of the Washita, interestingly enough. This makes me wonder if the scratch pattern left behind from the Washita responds better to an untreated strop due to... shallower valleys/scratches? Of course, I could just be judging the corresponding "grit" of my Washita incorrectly, but it already removes material faster than the 2400 grit waterstone I'm comparing it to.

As to weather stropping with compound vs stropping without improves my edge more off of say my Washita, Hard, or Translucent Ark, it's hard for me to say. I think it may improve the Washita and the Hard Ark more than plain leather, but the difference is not nearly as large as one would expect, and I think I'm able to get pretty comparable results with bare leather.

One last observation I have, though, is that I don't think people generally strop enough to get the full benefit of the green compound. Even finishing on my finer stones, I find that I need as many as 40-50 strokes to get a the full benefit of the strop, if not more, depending on how much pressure is used. And while some claim that worn-in compound works better, I find I still get better final results with fresher compound (granted, I guess it gets worn in fairly quickly with the number of strokes that I generally employ).

I'm still quite new to all of these mediums though, so this is all strictly my limited experience / early impressions.

[Jim Koepke]

One last observation I have, though, is that I don't think people generally strop enough to get the full benefit of the green compound. Even finishing on my finer stones, I find that I need as many as 40-50 strokes to get a the full benefit of the strop, if not more, depending on how much pressure is used.

One of the books in my library suggests no more than 10 strokes on either side of a blade when stropping.

Today off of my 8000 stone only 5 stokes on the strop were used on either side to get to a fine polish.

My strop is leather and is loaded with green compound from a lapidary supply store.

My experience with stropping much more than 10 strokes is the likelihood of rounding the edge.

jtk

[Pat Barry]

Stewie provided an interesting link on the stropping topic earlier. If you haven't checked it out you should. Also, I found the second page on this website very informative as well --> check it out https://scienceofsharp.wordpress.com...-strop-part-4/

[george wilson]

The likelihood of rounding the edge by stropping depends upon what the strop is made of,and your technique. I use a MDF strop which is not prone to round the edge unless the user lifts up the blade towards the end of the stroke. I don't do that,but many may. No telling what different people might do.

I wear a 1 1/2" belt custom made of hard English harness leather(The harness maker made it for me. Probably will outlast me!) I take the end out of the keeper and use its HARD suede side as a strop when sitting in the living room. It brings back my SLIGHTLY less than razor sharp ball bearing steel blade pocket knife blade,which I made, to razor keen ness. I take light strokes,and may do 100 if needed. There is no compound on the belt. Certainly gets the knife razor sharp again. I get about 8" of belt to strop on when I pull it out of the leather keeper. Only use about 3" to strop on. I CHANGE ANGLES a lot. That includes the initial stropping after honing the blade on the last stone.

I find I don't need to strop after the UF ceramic stone. It will get razor sharp just off the stone,easily shaving hairs. But,part of that is how I USE the stone. Angles,etc..

I repeat: ITS ALL ABOUT TECHNIQUE that you bring to bear on the strop. Not necessarily the strop itself,provided the strop is made of good material itself,properly compounded (for initial stropping just after stoning),etc..

[Pat Barry]

The likelihood of rounding the edge by stropping depends upon what the strop is made of,and your technique. I use a MDF strop which is not prone to round the edge unless the user lifts up the blade towards the end of the stroke. I don't do that,but many may. No telling what different people might do.

I wear a 1 1/2" belt custom made of hard English harness leather(The harness maker made it for me. Probably will outlast me!) I take the end out of the keeper and use its HARD suede side as a strop when sitting in the living room. It brings back my SLIGHTLY less than razor sharp ball bearing steel blade pocket knife blade,which I made, to razor keen ness. I take light strokes,and may do 100 if needed. There is no compound on the belt. Certainly gets the knife razor sharp again. I get about 8" of belt to strop on when I pull it out of the leather keeper. Only use about 3" to strop on. I CHANGE ANGLES a lot. That includes the initial stropping after honing the blade on the last stone.

I find I don't need to strop after the UF ceramic stone. It will get razor sharp just off the stone,easily shaving hairs. But,part of that is how I USE the stone. Angles,etc..

I repeat: ITS ALL ABOUT TECHNIQUE that you bring to bear on the strop. Not necessarily the strop itself,provided the strop is made of good material itself,properly compounded (for initial stropping just after stoning),etc..

George, thanks for the info. As a learning point for us, can you articulate how much force you use to strop on your MDF? Would you say it is high pressure or low pressure. How about when you charge the strop with fresh paste - do you use a lot of pressure then to embed the particles? How about the angle for stropping - do you try to replicate the angle used for honing on your stones or do you go to an even lower angle? Thanks

[Luke Dupont]

One of the books in my library suggests no more than 10 strokes on either side of a blade when stropping.

Today off of my 8000 stone only 5 stokes on the strop were used on either side to get to a fine polish.

My strop is leather and is loaded with green compound from a lapidary supply store.

My experience with stropping much more than 10 strokes is the likelihood of rounding the edge.

jtk

I've actually had no problem with rounding the edge, except for two exceptions that I'll mention. I use a backed leather strop, and if I test the angle that my chisel or plane iron starts cutting at, it is rarely changed much by stropping.

The two exceptions to this were:
1. When I used a very wet/loose compound that didn't stick to the strop, moved around, and therefore dubbed my edge.
2. When I was goofing around and trying to strop on my wallet, which is way too soft and has too much give. This dubbed my edge as well.

Of course, I guess there is no harm in going less - it will still help to remove the burr. But you won't get the full benefit of the strop.

Now, of course, if you are ending on a really fine stone (maybe finer than 8000), or the strop is in less than optimal shape, then there is a chance that it will degrade or just not improve your edge regardless of technique. I find this to happen if my strop is really dirty or something.

I always advocate experimenting and seeing for yourself, though! Try going significantly more, if you feel experimentive some time. Test the angle and the sharpness as you go. It's all in technique. As george says, a strop won't dub your edge, unless it's just entirely too soft or the compound isn't behaving properly.

[Patrick Chase]

One of the books in my library suggests no more than 10 strokes on either side of a blade when stropping.

I think that the overall point (that stropping too much increases likelihood of rounding) is valid, but it seems to me that the maximum number of strokes would depend on the strop in addition to the user's technique. As an example, an untreated fabric strop does next to nothing to the steel with each stroke, and so people can and do use very high stroke counts with good results. I've seen people advocate up to 100 or more strokes in that configuration.

On the other extreme a leather strop with honing compound does a fair bit to the steel with each stroke, so the limit will be correspondingly lower.

[Patrick Chase]

Interesting discussion.

One thing: I notice that people are always pointing specifically to the LV compound in these discussions. Do you have any experience with other brands / find any noticeable variance?

The LV is the only wax-based compound I've used, so I don't know how any of the similar bars on the market perform. I've seen it claimed that most of them ultimately come from the same supplier, but I haven't seen any documentation (MSDS/SDS/etc) to confirm that.

I've used the Tormek compound, which is an oil-based aluminum-oxide paste (no chromium oxide). It seem to work very well, and maybe leaves a slightly cleaner surface than the green compound. I've also used 0.5 um alumina powder on strops both with and without oil, with extremely good results.

[Sean Hughto]

Sayre: "In any dispute the intensity of feeling is inversely proportional to the value of the issues at stake."

[Trevor Goodwin]

The LV is the only wax-based compound I've used, so I don't know how any of the similar bars on the market perform. I've seen it claimed that most of them ultimately come from the same supplier, but I haven't seen any documentation (MSDS/SDS/etc) to confirm that.

Patrick here's one for you: http://www.flexcut.com/pw11-flexcut-...hing-compound/ Flexcut Gold. It's meant for carving tools. I think it uses a blend that is mostly titanium oxide. It works very well and has a good reputation. The Flexcut company recommend only stropping their knives and never take them to stones. I believe this is because the compound on a strop maintains the factory micro-bevel which makes the edge last a lot longer.

[Patrick Chase]

Stewie provided an interesting link on the stropping topic earlier. If you haven't checked it out you should. Also, I found the second page on this website very informative as well --> check it out https://scienceofsharp.wordpress.com...-strop-part-4/

+1 for scienceofsharp. I stumbled across that site a while back, and his SEM work is amazing.

I don't think that all of his conclusions necessarily hold for woodworking. In particular he's honing to pretty low tip angles suitable for razors, and has problems with tip "break-off" in some cases, for example here. My intuition is that that wouldn't be as much of a problem at common edge-tool angles, and that you might not want to sacrifice acuity at the very tip if you're starting with a more obtuse base angle.

[Stewie Simpson]

I have placed an order for a 60 inch length of 3.5mm x 76mm Cowhide Butt Leather from the U.K, to make up some new stropping paddles. The leather will be glued to the wood substrate flesh side down.

http://www.jwoodleathers.co.uk/leatherhide.html

Stewie;

[Stewie Simpson]

The Pure Chromium Oxide Paste arrived in the mail today. I completed a basis trial on the application of PCOP product compared that of the Chromium Oxide Wax Compound (COWC) to some old stock cowhide leather I had in my workshop.

The PCOP was very easy to apply. Only the smallest amount was required to cover a large area of leather. As you wipe the surface with your finger tip, you can feel the extremely fine granular polishing compound within the product. Wear rubber gloves when applying this product as it will stain your skin.

The COWC was a lot harder to apply to work an even coverage across the surface of the leather. As you wipe the surface with your finger tip, the surface feels very undulated and clumpy, with obvious signs of the fine granular polishing compound within the product.



I have read of recommendations not to use any petroleum products on leather strops, as its use long term can severely damage the strengthening fibres within the leather itself, potentially resulting in rotting of the leather.

As a test only, I rubbed the surface of the COWC vigorously with a Honing Oil to see if that allow the COWC to be more evenly spread across the leather. Due to the wax component within this product it made no difference.



I then trialled rubbing the surface of the COWC vigorously with Mineral Turpentine. Due to the wax component within this product it made little to no difference.



Stewie;

[Stewie Simpson]

When viewing the content of the Pure Chromium Oxide Paste, be aware that is all you receive within the supplied container. On opening the product, there was a very thin layer of solidified paste on top of the liquid paste below. That skin has to be removed and discarded as its not re-usable. Its represents a loss of usable product. To prevent re-occurrence at a later stage, I am storing this product in a refrigerator between use. I will make inquiries with the supplier to obtain some further advice.

Its important to note that I payed full retail price to personally trial this Pure Chromium Oxide Paste product.

----------------------------------------------------------------------
Chromium Oxide Paste 1 £15.00 £15.00
================================================== ====================
Subtotal: £15.00
Shipping (Airmail Signed): £11.00
Total (inc VAT): £26.00

Stewie;