"Showa" or "Dept of Interior" stamp?

[DaveR]

You could in fact describe quite a few of us, myself included, as Ohmura-san's "ardent fan"!

[Nick Komiya]

I came across a drawing of the contraption they used to do impact testing on the Guntos. The anvil-like weight they dropped on the blade weighed 12 kgs. So only the blades that passed this test got the Seki stamp mentioned earlier in this thread.

[Bruce Pennington]

Dang, that really good stuff, Nick, important history for the sword collecting community - Thank you!!!

[ghp95134]

I came across a drawing of the contraption they used to do impact testing on the Guntos. The anvil-like weight they dropped on the blade weighed 12 kgs. So only the blades that passed this test got the Seki stamp mentioned earlier in this thread.

Hmmmmm .... the French had it backwards ..... their blades were at the top, and impacted on the target below.

(^___^)

Image of Weidmann just before the "bend test".
source

[Kiipu]

Out of curiosity, I had a look at some other Japanese sites to see what they had to say about the 昭 in cherry blossom mark. The Ohmura site did not really explain what the marking was for, so my interest was in the purpose.
...
As to the origins for the mark, I understood that there were many cases of such mass produced blades snapping in the freezing cold weather of Manchuria. So the people in Seki decided to do voluntary impact testing on their products to ensure quality on blades for use by the military. They stamped blades that passed this test initially with the Kanji for Seki 関, signifying the guild. But later, one of the army arsenal factories happened to adopt the same kanji for marking, so the Seki people deferred and changed their impact test mark to the 昭 in cherry blossom mark for army orders and an anchor mark for navy orders. Anyway, that was what I took out from other sites.

I enjoy reading your various articles and posts and hope you do not mind a question out of the blue. You mentioned Seki used an anchor stamp on swords for naval orders. Can you provide a link to the website where you found this information?

[Nick Komiya]

Sorry, not anymore. It was in one of several Japanese sites found through a Google search, but I saved nothing of the page, as it was no topic of great interest to me.

[Nick Komiya]

Though I cannot tell you what sites I read 3 years ago, I was able to find for you a sword polisher's site that declines to accept swords with the Showa as well as the anchor mark for polishing. All swords on the page are examples of what he refuses to work on. You will find the reference to the anchor mark midway. お受け出来ない御刀見本 - 日本刀研磨工房

If you can be more specific about what you want to find out about the anchor mark, I might be able to get more to the point next time I do some browsing.

Of course, there is also my general discussion thread on navy anchor acceptance markings here, which includes swords.
Navy acceptance marking regulations

[Kiipu]

Thank you for the followup reply. I am trying to identify an encircled anchor marking that shows up on non-traditional made naval officer swords. See the link below for an illustration. When I read your statement about the anchor mark, I thought that maybe that could be the explanation for it.
Arsenal Stamps. - Page 2 - Military Swords of Japan - Nihonto Message Board

[Nick Komiya]

The navy acceptance marking regs define 4 anchor sizes of 15, 10, 6, and 3mm. Of these, metal items (including swords) were to use the 3 and 6mm size anchors. Furthermore when the production flow involved multiple quality checks, later checks were to get the larger anchor sizes or the marking location needed to be selected in a way that pointed to the section that had been checked. In case of the army, a triangle stamp was applied when the material passed inspection and interim checks gave out the W mark, ending with the army star earned at the final inspection.

The navy further used the 10mm marking as the material inspection mark and the 15mm anchor as the final acceptance (equivalent to the army star). Non-metal products were to use the 6mm and 10mm stamps.

I will keep my eyes open for the anchor in the circle, but let me know the metric size of the anchor, as size matters greatly in the navy as seen above.

[Nick Komiya]

Here's a site that suggests that the anchor in the circle had the same meaning as the Seki or Showa in cherry marking. So, here, the anchor marking is discussed within the same context as the polisher's site, namely swords treated as not representing any artistic value under Japan's registration law. It says that these markings were normally intentionally ground off after the war in the hope to sneak them through the registration inspection and those that still retain them are rare.