What is the purpose?

[Ooitame]

Hello all,

 

What would be the reason for a back plate on a shakudo menuki?

[b.hennick]

Here is a suggestion. It is  suggestion because I am not sure. If the shakudo is thin, the tsukaito could crush it. This would spread the force out as there would be more surface area and so less force per unit area.

I have had iron menuki that had a similar filling. There would be no chance to crush iron menuki.

[Brian]

What is the backing material? Looks organic rather than metal? Is it pine pitch mixed with something or....?

[Ooitame]

Thank you Barry, I believe you are correct.

 

Hi Brian, no idea... awaiting there arrival. I will msg the seller and try to find out more.

[Yasaka Azuma]

Maybe it's because I don't understand your writing well. Is it a quiz that you don't try to show the front side?
The kibata, which is slightly visible in the image, is well carved, and the shakudo is also in good color. The kobakuchi (edge) on the back side is also thin and evenly finished, so it may be the work of Goto School in the early Edo period or related metalworkers.
If I  can't see any of the ne (pillars), it is possible that they have already dropped out. What is difficult to understand is that the mugi-urushi that fills the back of menuki remains new, and there are no visible marks glued to the katana handle. Genuine mugi-urushi becomes stone-hard over time and is often impossible to remove.
The image is a modern cast menuki. The back side is filled with resin to cheat that it is a casting, and it looks like a mugi-urushi. That is not the case with your item. It's just a reference.

 

[Ooitame]

Hi Yakozen, thank you for your reply. I have not considered missing pins (ne). I am having a Koshirae built for a sword I bought. I was hoping to show when complete for some discussion and kantei. However, I see your point of view and will show the menuki early. I have asked the seller about the back/plate/fill material and if the pins are intact. What school would you or others think these are from?  Other comments are welcome.

Measurements:

Length 1: 2.95cm x 1.44cm

Length 2: 3.01cm x 1.34cm

[Katsujinken]

Perhaps they were modified for decorative use on something other than a tsuka?

[Yasaka Azuma]

Thank you Eric, for publishing the image. Let me correct it, this is not an iebori like the Goto family. The style is machibori's shishi.
Therefore, I think that the era is newer than the middle Edo period (1700 A.D.), not the early Edo period.

[Ooitame]

Thank you for your reply Yakozen. I was oroginally considering late Yokowa school, as I have seen some similarities. Although, smaller (non out stretched) legs/paws on shishi is harder to find from them. However, Yanagawa, or Omori are also possibilities. I am leaning more towards Omori. Tosogu is a tough subject! 

 

I have heard back from the seller, the filling was glued in at some point, they, as Barry, stated, was most likely done for support.

[Tanto54]

Dear Eric,

 

As Yas said, the "Backing Material" or "filling" is a mixture of urushi (lacquer - or the sap of a certain kind of tree) and other materials.  Its purpose is not “support” (meaning to keep the menuki from being crushed - as Barry said, that would not be necessary in his iron menuki).  Instead, it is an adhesive or leveler.  The mixture may have several different names depending upon the use and materials mixed with the lacquer.  Mugi-urushi or nori-urushi is lacquer mixed with wheat or rice flour to make a glue.  Sabi-urushi has powdered burnt clay mixed in for building up or leveling things.  Kokuso-urushi has sawdust or plant fibers mixed in with wheat/rice flour and urushi to make an adhesive filler putty.

 

Remember that Menuki are sometimes glued to the tsuka (handle) and do not have ito or tsukamaki (the cord often wrapped around the handle) to help hold the menuki in place.  One of the urushi adhesives mentioned above can be used to fill the back of the menuki and glue them onto the tsuka (e.g., a bare samegawa - ray skin - handle).  So even if your menuki were wrapped with ito or tsukamaki, perhaps they were not at sometime in the past.  The other reason that these urushi mixtures are sometimes used is as a “leveler”.  Remember how the nodules of the samegawa or ray skin can be bumpy and uneven.  Also consider how the edges of the backs of the menuki are slightly concave and may not sit perfectly straight on the samegawa.  Therefore, one of the filler urushi mixtures can be used to “level” the menuki on the ray skin and keep them from shifting (even if they are covered with tsukamaki)...

 

The filler on your menuki looks like Kokuso-urushi to me (it appears to have sawdust/plant fibers mixed with the lacquer).

 

Here's a beautiful example of a glued menuki from www.yuhindo.com