Hamon question

[Kevin McGovern]

Below is a kwaiken I have been playing with when time allows. It is 1095 with a clayed back heated to 1475 and soaked for ten minutes then quenched in warm canola oil. After hand sanding up to 2000 and polishing with a rubber block and 1500 ao powder I etched for 15 seconds in dilute FC. Below is after another polish. I am concerned about the left side area behind the tip on the edge. That area came out in the etch and does not polish out. It is not present on the other side. Anyone know what this could be, and if it can be corrected? Thanks in advance.

just to clarify, the area surrounding the anomaly appears darker, because i polished this area extra to try to get rid of the offense. It is shinier and just looks darker.

 

[kuraki]

Kevin I think that's decarb that didn't get sanded away when you finish sanded.

 

[Kevin McGovern]

I don't think that's possible. I left the edge at .02 or so prior to heat treat. It is a frog hair away from a zero edge now.

 

[Matt Rochester]

It also looks like decarb too me. I know a frog's hair is small but I haven't actually measured one:friendly_wink:. What is the edge thickness?

 

[Kevin McGovern]

I don't have my micrometer with me, but here is a pic with a dime for comparison.

 

[Matt Rochester]

The tip still looks a bit thick. Is there any chance the thicker area is partly where your spot is?

 

[Kevin McGovern]

I think what looks like thickness is a shadow, it is pretty even to the tip. I can probably take a little bit more off that side where the spot is. Thanks.

 

[Stacy E. Apelt - Bladesmith]

It looks a bit like you may have burned the steel somehow.

Here is what I would try:
1) Sand well with 220 grit paper until it is gone or the tip is ruined.
2) If it went away, sand back up the grits and finish the polish.
3) If it didn't go away, grind back the tip to remove that part.

The other thing it could be is nie/noi. The steel could have cooled too much at the tip during quench and developed a bit of a pearlite/martensite "cloud" at that area.

 

[Kevin McGovern]

Thanks Stacy. I was very careful not to burn it, maybe too carefully and I didn't get all the decarb. To be honest, I can't really remember how thick it was pre-HT. It's been in a box for a month or so.