My first hamon disappears with polish

T

T.J. Fears

Joined
Apr 2, 2013
Messages
6
I have made a katana style machete from Admirals 1075. I differentially heat treated it using furnace cement. It was quenched in warm water for 3 seconds and finished off in mystery oil from 1550°F. I hand sanded it with 80, 220, 320, 400, 1000, 1500, and finally 2000 all under running water. I have etched it with lemon juice, 6% white vinegar, and 4:1 H20/FeCl. The hamon shows up very well with any one until I polish it. With polish it goes away about 99%. I have used oil and 0000 steel wool, Cloverleaf 800 grit lapping compound, Flitz, and Brasso. It goes from a mirror polish/no hamon to dull grey with awesome hamon. I try to lightly polish it to get the mirror back and a kill the hamon. What am I doing wrong.
 
I picked some of that steel up because I wanted some 1075 that I didnt have to forge into the proper thickness and to be honest getting a hamon out of it has not been going well. Sometimes I would see something after etching but to get it to come out isnt working. Gonna try a couple more times but not sure of exact specs for the steel. I can get great hamons out of aldos 1075, 1095, and W2 so I know its not necessarily my technique.

Ofcourse then again I also got some 1095 from them on that order as well. I made two blades out of it and when heat treating and quenching in parks 50 they both had cracking. One was just a single crack, the other I could hear it popping almost like it was a piece of glass. I was very suprised.
 
With 4:1 H2o/FeCl, It should take only 3 or 4 cycles of etch/flitz to get something that stays in dramatic fashion. How long are you etching for in the ferric solution? I use a minute at a time.
 
I'm new at this so I'll simply ask it as a question. Couldn't he simply be polishing the etch right out? Can you get a good etch on a mirror polished blade?
 
When you say "polish it", how are you doing the polish. A buffer will kill a hamon in seconds. Polish by hand, and try to stay off the hamon.

Here are a few tricks:
1) Etch and get the hamon the way you want it. Put nail polish over the hamon, closely following the frosty edges and any utsuri. Carefully polish (by hand) the ji ( surface above the hamon). Once it is as you wish, remove the nail polish with acetone. The ha (edge) will be gray, the hamon white, and the ji shiny. You can vary this technique to polish the ha, too.
2) Use small polishing stones to burnish and polish the ha and the ji. These are called jizuya and hazuya. Use a tongue depressor or your other thumb to keep them off the hamon while polishing.
3) etch the hamon selectively. Use a Q-tip and etchant to get the hamon to stand out. It is sort of like painting along the hamon. Wipe off any drips or runs with a damp cloth.
4) try a different etchant. 100:1 hydrochloric acid works well on stubborn hamons. 10:1 FC works well, too.
5) Leave the ji and ha dark. I like a Flitz finish with a white hamon. Some blades just should not be mirror polished.
 
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I read in a previous post that someone used white vinegar to bring out a hamon. Is that effective? I have a knife in O1 that a friend wanted differentially hardened with clay. I told him O1 is fine with straight hardening and tempering and very unlikely to show a hamon, but he insisted. When I got to 400grit, I could see the slightly different colors in the steel, following where the clay line was. I quenched in canola oil at 150f, after a 10 min soak at 1525 in the forge (out of the direct flame behind a steel baffle.) I will try to take pictures, but my photography skills are lacking. I have HCL here, but haven't sourced the ferric chloride locally yet.
 
Salem Straub - I have soaked it in 6% vinegar twice each time for 5 minutes. I hand rubbed everything else in: lemon juice, different vinegar, and the FeCl. I usually hand rubbed it for about 5-10 minutes. I have done about 10 different hand rubs. each time produced a very distinct hamon. The flitz made it almost invisible.

Stacy - I did not buff it with a buffer. I have used hand buffing with paper towels or old cotton tee shirt material. I think I will end up following your procedure.

Willie71 - I am pretty sure you can make FeCl from HCl acid very easily. Google it for details. O1 is deep hardening. It will show something but not a highly active hamon.
 
The hamon is a rough surface on a micro scale, when you polish it you make it not rough, stay off the hamon with your glitz and you should be fine

-Page
 
W1 or W2 would be a much better steel choice.

The Mn is really too high in 1075 for a lot of hamon activity.
 
Yes, I have 24" of W2 specifically for this, for future projects and some 1095 on order. The O1 was an accident. I didn't think it would show anything and was surprised with what I saw. Its faint but its there, right along the clay line. :)

@ TJ Fears, I have used the cotton pads available in the pharmacy for buffing small items, the ones used for makeup removal, or face cleansers. They are really consistent in texture, and buff finer than even the softest kleenex I have tried.
 
I have experienced the same exact problem, with various steels, over the years. Put it in the Fc and the hamon looks great, but it simply disappears when you start to work it. When I did encounter this problem, I have never gotten a satisfactory hamon. I think it's due to the blade not reaching full heat. Another possiblity, and a strong one, is the clay is popping off before the quench. I've started letting the clay dry on the blade for a couple of days, just to make sure it's truely set. I've gotten to where I hate hamon's, yet I keep coming back for more and more, like an addict. In fact, I'm starting a project soon, with W2. Cross your fingers, Brothers.
 
bladsmth said:
When you say "polish it", how are you doing the polish. A buffer will kill a hamon in seconds. Polish by hand, and try to stay off the hamon.

Here are a few tricks:
1) Etch and get the hamon the way you want it. Put nail polish over the hamon, closely following the frosty edges and any utsuri. Carefully polish (by hand) the ji ( surface above the hamon). Once it is as you wish, remove the nail polish with acetone. The ha (edge) will be gray, the hamon white, and the ji shiny. You can vary this technique to polish the ha, too.
2) Use small polishing stones to burnish and polish the ha and the ji. These are called jizuya and hazuya. Use a tongue depressor or your other thumb to keep them off the hamon while polishing.
3) etch the hamon selectively. Use a Q-tip and etchant to get the hamon to stand out. It is sort of like painting along the hamon. Wipe off any drips or runs with a damp cloth.
4) try a different etchant. 100:1 hydrochloric acid works well on stubborn hamons. 10:1 FC works well, too.
5) Leave the ji and ha dark. I like a Flitz finish with a white hamon. Some blades just should not be mirror polished.
Click to expand...

This ^, although I only etch to find the hamon in the first place, and I replaced the jizuya with grades of Micromesh from 4000 upwards.
If you've done enough with the hazuya the white frostiness will stay even when you polish the surface with the other grits (of micromesh & using water only).
I think flitz, autosol etc. not only polish the surface but fill in the voids in the rougher surfaces. The hazuya stones seem to give a surface somewhere between 2400 grit and 3600 grit.
The "scratches" it leaves are retained for longer in the hardened part and polish out quicker in the soft parts. Polishes just buff everything the same irrespective of hardness.
 
I'd like to see pictures: before etch, after etch, and post polish.

I've seen a LOT of guys try to bring things out in steel that aren't REALLY in it.

A really good hamon will show up at a 50X rough grind and no etch (in the right light).
 
But Nick, if you can see a really nice hamon after it comes out of the Fc, is it there or not? It's just plain weird, I see it, and then it simply vanishes (well, almost anyway) during the sanding and polishing. And I sand very carefully.

I do agree, the few times I've got a nice hamon I could see it even without the Fc. Just doesn't happen very often, Lol.
 
After HT I do a quick grind to see that I have a good Hamon (Activity and Location)... You can see it easily right after you take it off the belt if held at the right angle in the right light.

I would lose the Steel wool and use Cotton makeup pad (Thanks Nick) with Green Liquid Flitz to polish.
 
What you are doing with sanding and polishing is leveling the high spots to meet the low spots and in extreme cases smearing the surface. A hamon is a delicate surface effect that shows the underlying crystal structure as it breaks the surface plane where different crystal structures at the surface reflect light in different ways unless you get some oxide coloring from alloy elements. If you buff and sand it of course it disappears except for the basic differences between hard and soft areas. That is why a japanese polish is done with loose grit hand rubbed. if you look at a real prewar japanese blade, or any that are done traditionally under magnification, the surface is not smooth, there is distinct topography where different crystalline structures resist abrasion in different ways and that topography interacts with light in different ways. With the FC etch you are sort of cheating a bit as the different phases of the steel crystal structure etch differently creating the same effect, and alloying elements react and color the etch to really make it pop sometimes, but then if you buff that you lose most of it as you smear that wonderful topography down into the valleys. If you don't believe me get a microscope out and look yourself.

-Page
 
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