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Stropping on CrOx/FeOx reduced blade quality?

I've applied CrOx/FeOx powder to the balsa strop from Whipped Dog a couple of times. When I ran my John & Ragg over it last night and inspected the edge under a microscope, it looks as if the blade edge is slightly damaged.

It appears, by examining the before and after images, that there are microscopic nicks on the blade edge after running the blade over the CrOx/FeOx pasted strop.

What's going on?

(I'll post images once I figure out to get them off the SD on the microscope)
 
I would suspect contamination, dirt, dust or silica from balsa. Pasted paddles must be kept covered in a sleeve to prevent contamination, just from laying on a dirty/dusty bench.

Paste a clean piece of cardboard, inside of a cereal box, joint the edge straight and bring back to meeting and see if the paste chips another blade.

Typically, new stroppers on paddles use too much pressure.

If the blade was hand sanded, or buffed it is not uncommon for edges to chip after the first honing if the bevel was not well set.
 
I have found that the balsa I used caused the problems so I used denim from old pants for my pasted strops. You can either attach to a paddle or make a hanging strop. I also prefer the black paste to others for a finishing paste. Its slower but also more comfortable for my skin.
 
All good feedback, I'll go through each a bit later. Is it also possible that I applied the paste too thick?
 
Could be, and it hardened. With paste less is more. I only apply, 3 inch X’s about ½ inch wide. That is plenty and once a strop is pasted it lasts years for razors.

For knives and tools, they build up swarf and edge burrs,turn black much more quickly. I scrape the leather clean with a sharp card scraper or knife and reapply.

Was the razor hand sanded or buffed?
 

Slash McCoy

I freehand dog rockets
All good feedback, I'll go through each a bit later. Is it also possible that I applied the paste too thick?
I would be surprised if you did NOT apply it too thick. Everyone does. If it looks like just enough, it is probably about 3x too much.

The secret for me was lapping the balsa, and applying barely any, and rubbing it in good, then wiping the surface clean so there is NO coating, only abrasive embedded into the balsa.

I do not care for FeOx or CrOx. YMMV but I find them slow and variable, with the light pressure that we use with diamond pastes. I was able to make it work and deliver quite a nice edge, but it takes longer. Pressure is the enemy. Long strokes cover a lot of ground quickly but ending with very short x strokes and pull strokes adds a lot of refinement to the edge and ensures that there are no artifacts hanging on the edge. If you read the pasted balsa strop thread and do the same except with 3x as many laps, you will be in the ballpark. Feedback is almost non existent so you just have to count laps and look at the edge. maybe do a treetop or two as you go, and see what the shave test gives you at the end.

One thing a lot of beginners do wrong is paste the same balsa with two different grades of abrasive, one on one side, one on the other. It doesn't take much to contaminate the finer with stray particles from the coarser. FeOx has a nominal grit size of .1µ and CrOx between .3µ and .5µ, with all that variation within one sample. So on a background of FeOx finished bevel face, just a few scratches from the CrOx stands out pretty good. The good news is it might still shave pretty good.
 
I've applied CrOx/FeOx powder to the balsa strop from Whipped Dog a couple of times. When I ran my John & Ragg over it last night and inspected the edge under a microscope, it looks as if the blade edge is slightly damaged.

It appears, by examining the before and after images, that there are microscopic nicks on the blade edge after running the blade over the CrOx/FeOx pasted strop.

What's going on?

(I'll post images once I figure out to get them off the SD on the microscope)
If you Google Abrasive Particles under the SEM. You can find SEM images of TI white paste. This abrasive can contain particles in the 10-12 micron range. I.e. particles equivalent to a 1k stone. For this to work the abrasive needs to be worked into the substrate. It will also require, as have been mentioned, a minimum of product.
Too much product, combined with too many laps with pressure will probably not be good for the edge.
I only tried the TI paste one time on balsa. It did not do anything positive for my edge.
Crox is a little better in my opinion. It also needs to be of good quality.

I have had better results with CBN on balsa.
 
First - shave with i=the blade and see how it feels. we don't shave with our eyes.

Every abrasive contains particulate greater and smaller than its alleged 'grit'.
Depending on the abrasive, the numbers may or may not be important. Most people don't even understand how grit is determined, particles are not measured with a rule or a scale. Forget grit, it's almost irrelevant.
What matters is results, not numbers, not pictures.

No edge is a 'perfect' line. The more magnification you use, the worse things can seem to be.

FWIW - most Crox is not all that highly refined and it is not uncommon for it to leave less than stellar edges. I am talking about feel, not looks. Coticule bevels can look awful, but can also deliver wonderful shaves.

Crox, like - the stuff you get in blister packs in auto shops, is often not even all Chromox and ungraded. So you can wind up with a lot of sharp and not so much smooth. Esp when applied badly, and used with too much pressure.
You wrote that you applied the substance more than once - I would suspect there is too much compound on your strop. Crox needs to be reapplied verrrrry infrequently unless you are honing a ton of blades.

FeOx falls into similar categories and situations.

This doesn't mean you can't get a good shaving edge from the stuff. People have been using it, and some are good to go with it.
But, some people are less attracted to it than other abrasives and sometimes getting a better quality product can help. Applying and using it correctly is key.

Too much compound on the strop will always cause issues. It should go on like a faint dusting, not a layer.

I prefer abrasive compounds on cloth. It's more flexible and less prone to pushing back at the steel. Very light passes, only a few of them - like, 5-6 passes over 5-6" of surface is usually more than enough. Trying to bring back an edge that is too far gone will often result is enhanced roughness. Takes time trial/error to figure out; one-size-fits-all recipes usually don't fly.
 
Great feedback everyone! Thank you!

First some background. My adoption of the CrOx/FeOx balsa strop from Whipped Dog was pivotal for me. It's allowed me to continue use of my Ralf Aust for 48 shaves.

The Whipped Dog balsa strop has CrOx on one side and FeOx on the other. He sends it wrapped in newspaper. I now have it wrapped in waxed paper.

The error I made occurred when refreshing the paste. I applied too much FeOx powder. I can correct this with @Slash McCoy ’s advice. I've purchased Red Velvet and Tomo-Chromo sharpening compound from TomoNagura and will use this (applying powder and mineral oil free hand, as required for the Whipped Dog balsa strop is too variant). I've also purchased balsa wood, so I can make a better strop surface.

And how was the shave? Good. Post-shave treatment, I notice some stinging, but it was not uncomfortable. I decided to take the blade back two steps in the progression and see the difference. Also good, but not as close. The step I took it back to was whetting on a Nagura Mejiro slurry on a coticule.

I took the blade back -2 then -1 in the progression -- Mejiro slurry followed by finishing on an Arkansas Black with honing oil to see how that felt. Unfortunately, before I could shave with it, I damaged the blade edge when measuring its sharpness on a BESS test fixture. Lesson learned on how to use that device.

Regarding stropping, after I take a blade back to the stones (or paste) I end with stropping on leather 70 laps.

Regarding using a microscope, it's an essential part of my process. Through blade use (shaving) followed by inspection (microscope) I've leaned when a shave is going to be poor just by inspection alone. Because I'm still learning, when I see something that looks off, inspection is not enough. That's where you fine gentlemen fit into my education!
 
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