Thread: Scratch pattern pictures

Originally Posted by Bart

I decided to go ahead and remove the smile on those Double Arrows. I took me almost a full day, and heavy backache the next day , but I now have 8 razors that are easily "honeable" in my drawer, all HHT-positive after the DMT 1200.

I've also put a razor-performance-sheet together, that we can use to compare the differently honed razors. I call upon anyone reading and caring about this experiment to review the document (see attachement). I would like this thing to be as solid as possible, before we start using it.

Thanks for your attention,

Bart.

hey Bart, I really like your attached form. A great way to systematize things. Looking forward to the results.

We finished the first round of test shaves.

After some consideration we decided to hone the razors with the following progressions:

Razor 1: DMT1200 till HHT positive / 100 laps on clean leather
Razor 2: DMT1200 till HHT positive / 100 laps on Coticule A
Razor 3: DMT1200 till HHT positive / 100 laps on Coticule B
Razor 3: DMT1200 till HHT positive / 100 laps on Coticule C

All coticules were used with water only (+ a drop of dishwashing soap)
As explained before, there are 2 groups of 4 razors and they are randomized in order to do all shave tests without knowing which razor received which treatment. A standardized form is used to keep track of results. I've attached a picture of the Coticules.

The first results are not impressive. With exception of the DMT-edge, all razors performed more or less the same: they felt smooth to the face, rather promising with the grain, but not living up to that when going against the grain. There was a very mild pull. No post shave irritation. All within acceptable limits. The real downside was closeness. The razor left something like a 5'O clock shadow. (We decided up front to do one pass WTG and one pass ATG, and leave it there)
The DMT edge performed similarly, but with a bit more pull and some mild irritation. Closeness was the same. (I compared my well used DMT to a new, freshly broken in, DMT recently. The difference between those two was strikingly: The new DMT was much coarser, even after lapping a coticule with it and honing razors all night. Under magnification, both scratch patterns looked very different, we even wondered for a while if the new one had a defect.)

Trying the interpret the results, I'd say that the Coticule edges were all (equally) smooth, but they all lacked keenness. I suspect the edge width of the DMT being not fine enough for great shaving results. The coticules performed well on polishing the bevel, but not on refining it. I have banished the Belgian Blue to my woodshop some time ago, assuming it could not do anything that the Coticule couldn't do better. I suspect to improve the keenness of the above honing paradigm, we need to add some mediator between the DMT1200 and the coticule with water. Could be a coticule with slurry (but that would introduce the slurry-effect in the process), or a DMT-8000 (not in our possession), or the Belgian Blue (reported to display less of the slurry-dulling effect than his big sister Coticule). In a later phase we'll compare those three possibilities in one experiment, but for now, we are focused on the differences between the three Coticules.
Hence, for experiment 2 the honing plan is this:
Razor 1: DMT1200 till HHT positive / 50 laps on BBW
Razor 2: DMT1200 till HHT positive / 50 laps on BBW/ 100 laps on Coticule A
Razor 3: DMT1200 till HHT positive / 50 laps on BBW/ 100 laps on Coticule B
Razor 3: DMT1200 till HHT positive / 50 laps on BBW/ 100 laps on Coticule C

All coticules are used with water only (+ a drop of dishwashing soap). The Belgian Blue Whetstone is used with a slurry (milk-like consistency).

This second experiment is still in its early stages, but the first results show a very clear improvement in closeness of the shave, and also seem to reveal some differences between the coticules. It is too soon to draw any real significant conclusions, though.

regards to all,

Bart.

Are those custom razor boxes? I'd like to see more of those! lol

Yes, they're custom. Just a solid block of Merbau, with 4 deep pockets for the razors. Finished with a quick coat of yacht varnish.
They're made in a few minutes with a stationary chain mortiser.

I could make them for you, if you like.

Bart.

Series 2 of the hone experiments is closed.

I present the results in a PDF attachment.

The resulting edges are definitely better than the edges of series 1, that we only honed with 100 laps on a coticule with water after the DMT-E.
The 50 laps on Belgian Blue with slurry in between the DMT and the Coticule make a clear difference.
The Blue-only edge (1D) is slightly less keen and causes some irritation.
One of the three coticules might be performing slightly less, although the difference is not big enough to be of much significance. It might very well be that it's just a slower hone, and that 100 ultralight laps, simply is not enough .

All in all, these are certainly decent edges.
But we're not yet at the end of the scale, and we are setting up the next experiment, that opens horizons for better edges. The hyphotesis of this new experiment is that 50 laps on the Blue and 100 on the coticule is not enough to completely remove the coarser marks of the DMT. If, for the sake of science, you hone with a toe leading X-stroke on the DMT and with a normal heel leading X-stroke on the Blue and the coticule, it is fairly easy to see under magnification that the 50 on the blue and the 100 on the coticule are not enough to completely remove the scratch marks from the DMT (that run in the other direction for a better visual). Doubling the amount of work on the blue and the coticule, however better, still does not completely remove the DMT-scratch marks.
I occured to me that the easiest way to make sure a cutting edge is build by nothing else than the final hone, is to use Tim Zowada's tape honing method. So, after the DMT and the Belgian blue, I added a double layer of tape to each spine and performed 20 laps on one of the coticules per razor. This creates a small, but clearly visible (at 40X magnification) secondary bevel, carrying only the scatch pattern of the hone in question, and in therory also offering the maximum keenness that particular hone can provide.
I have compared two such edges during one shave, and the results are impresive enough to go ahead with a full experimental round. The score of the razors improved with about 4 to 5 points, going from 19/30 to 24/30. We'll see if more test schaving comfirms these promising results.

Together with the results of the closed series, I'm also attaching a picture of a secondary bevel edge.

Bart.

I hate to revive a long dead thread, but when it's this good...

Actually, I dredge this thread up and look at the pictures every few weeks. That and the TZ bevel pics...and the Microscope analysis of the Japanese hones.

Originally Posted by FloorPizza

I hate to revive a long dead thread, but when it's this good...

Well Sir, it's not dead, just dormant till Kris and I find time to analyze the test results on the last experiment.

Thanks for the encouragement,

Bart.

Originally Posted by Bart

Well Sir, it's not dead, just dormant till Kris and I find time to analyze the test results on the last experiment.

Thanks for the encouragement,

Bart.

Man, Bart, I look forward to seeing the results of your last experiment! And I didn't mean the "dead thread" thing in a bad way by any means... I thoroughly enjoy following your results.