hamon help

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lratclif

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Feb 22, 2013
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I have a problem when it comes time to etch and bring out my hamon in my knives. I use 1095 that I grind, drill, normalize, clay treat and quench in parks and get a really good differential HT out of it. I got on to finish grinding and hand sand down to 2000 grit WD. At this stage I etch in ferric for about 10-15 min and while the blade goes into the etch very smooth and level after hand sanding it comes out with light grooves lengthwise down parts of the bade almost like there is small strips of metal that the etch is more effect to than others. It looks like I stopped hand sanding at 220 in some places, I was wondering if anyone else has had this problem and if so what am I doing wrong?

If it helps this problem seems to be most prevalent in the transition area and in the softer metal, the hardend edge does not get this problem nearly as much if at all.
 
Several things. First, how clean is your 2000 grit finish? In other words, did you get all the scratches out from 220 before you went to 400, 800, etc? And how do you know you did? The best way is to sand at a different angle for each grit up to at least 600. With all scratch marks running the same direction, it can be easy to miss a deeper scratch unless you specifically avoid it. My guess is that you might already be doing this.

Second, 15 minutes is a long etch in ferric chloride. Is it diluted? How much? I typically etch for 30-40 seconds in a 3:1 water:ferric mixture. I may do this for several cycles, polishing in between.

--nathan
 
I do my hand sanding in alternating directions like you mentioned to avoid missing scratches from the previous sand paper. The ferric is a 4:1 water to ferric mixture. I will try shorter etches and see if that helps, my first etch is long then I usually polish and do much shorter etches afterward polishing between the etches.

I was looking at some pictures on other websites and think that this could be a problem with alloy banding, what do you think? Could that be it?

It sure looks a lot like this http://www.knifenetwork.com/forum/showthread.php?t=30162
 
15 minutes seems like a long time to etch for a Hamon in ferric. When I use ferric to etch a Hamon I use a cotton swab and just wipe some on. Just enough to darken it. Then I start polishing and doing my routine.
 
Ok thanks for the help guys, I will shorten my soak time or try the cotton swab etch and see if that fixes things, thanks again.
 
Try adding several drops of Dawn or other dish soap to your diluted FC. It's a wetting agent and ensures even coverage with
less chance that bubbles develop and sit on the blade surface & inhibit the etch. This works with a swab as well and has saved
me some sanding.
 
Like stated start with a 10 or 15 sec dip, wipe it down with cotton swabs, another 10 sec dip, then repeat with wiping and 2 sec dips for a few times. This should be good enough.

There are a couple of different other factors also. How was the clay layed on and how thick. If its really thick and even then you can get just a temper line without all the different patterns. Temperature plays a big role and also quenchent. Ive only done a few hamons with 1095 but have gotten great results. Try and nail the target temperature that your aiming for say 1475 or so, let it sit for 10 minutes then quench right away. Hopefully your clay stays on nicely or breaks evenly. How the clay holds and breaks will also affect the hamon. There are alot of little tweaks that can really change the results.

Lastly and maybe most importantly is where did you get the steel from. Batch to batch and from different suppliers will have a effect on how the steel reacts. As you assumed it very well could be due to the steel banding and maybe makeup of the steel.

Thats my 2 pennies. I think the temps, quench, temper and steel makeup play a much bigger role in the hamon then the etch and sanding.
 
D.Crawford said:
Try adding several drops of Dawn or other dish soap to your diluted FC. It's a wetting agent and ensures even coverage with
less chance that bubbles develop and sit on the blade surface & inhibit the etch. This works with a swab as well and has saved
me some sanding.
Click to expand...

Forgot to add that. That's great advice
 
There are good hamon tutorials available by search, so I won't go into the whole thing, but there are several parts of your problem that are major.

Time - Long soaks in 3:1 FC is fine for getting a deep etch and topography on a damascus blade, but in a hamon it is way too long. Short repeated dips is the way to go. Sometimes it is dip, wipe with steel wool, dip, wipe, etc for an hour or more. Other times it is carefully applying the etchant with a Q-tip.

Concentration - The FC in hamon development is 10:1 up to 50:1. Some use vinegar, lemon juice, or 100:1 nitric acid. The thing is that it needs to be weak.

The lines- When a bar of steel is put in FC and just left there for a long time, the bubbles rise from the steel surface. As a bubble runs up the surface, it grabs other bubbles on the way, wiping them off the blade. This exposes the steel along that track to fresh FC. This will cause the bubble tracks to etch deeper than the rest of the blade. Once a track gets started, the problem increases, and the line becomes a deep groove.
 
Thanks for all the great advice guys, I will absolutely try weakening the FC and doing shorter soak times with the dish soap. As far as the clay procedure I used, I do a very thin layer followed by a thicker layer (roughly 0.2") thick and the clay I use is Satanite. I watched a few very good "how to" vids and they covered applying the clay and the ones I watched only worked with vinegar and lemon juice and that may be where I went wrong. I happened to have FC on hand from my college days and used that and didn't even consider the huge variation in ph. The steel is 1095 from Admiral steel.
 
Should be good steel then, Ive got some great results with Aldos 1095 with the few hamons Ive gotten the chance to try. I have used FC to bring out all my hamons with good luck. Just very short periods in the mix. Seconds. Other then that sounds like a good start.
 
Haven't used 1095 in a long time, but last blade I did with 1084 and a 15 minute etch came out fine. I'm wondering if you'r maybe getting alloy banding? Might try a higher heat for the first normalize heat, then lower the temp for the rest. Steel from Aldo should be clean and good, which was my first though, dirty steel. Of course my etch is a mix of feric and water, approximately 5 parts water to 1 part feric so it's a slow etch. How clean is the blade before etching? Any streaks left on the blade will resist the etch.

Got any pics? That would help.
 
I never submerge a differentially hardened blade in Ferric. Even if you only dip the blade in very shortly, you are most likely to bring things out above the transition that you don't want.
 
I think the post above are on your issue. But make sure the blade is very, very clean befor you etch. Especially if you are sanding with oil or something other than water. Even be sure what you use to clean the blade with before etch is cleaned off. If you clean with acetone follow with alcohol or some good dish soap.
 
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