Silly question on tsuba thickness.

[Alex A]

Thickness at the seppa dai, 

 

Dont know much about tsuba but know 6mm is not uncommon for tsuba, does anyone know if tsuba thickness goes further beyond this?

 

Cheers

[ROKUJURO]

This seems to be a general thing. A thickness between 6 and 5 mm is often seen, but there are rare exceptions up to 10 mm, and many early iron TSUBA of the TÔSHÔ and KACHUSHI type are much thinner.

[Alex A]

Aye Jean, i was curious enough to go through Aoi tsuba a few weeks back and from memory never saw one much thicker than 6mm.

 

There is a reason, im not going mental lol

 

Have a koshirae where it would be easier just to find a real thick tsuba rather than start messing around with finding real thick seppa

 

One of those things where eventually it gets worked out.

 

 

 

Cheers

[Scogg]

Probably not relevant to what you're looking for, BUT

Early Type 95 shin-gunto tsuba were 11mm thick! Later they shrunk them down to 9mm. 

So even up to the late 1930's, very thick tsuba were being made and used en masse.
-Sam

[DKR]

This one is probably 3gen Akasaka .

Seppa dai 9mm thick.

Inside of the nakago ana you can see traces from the chisel.

[Steve Waszak]

I have an Owari sukashi tsuba (Momoyama) with a 7mm rim, and a Kanayama guard (also Momoyama) with an 8mm rim.  Not common, but they do exist.    

[Alex A]

Is there a reason there are these real stocky tsuba?

[cluckdaddy76]

Here is a brass tsuba that is 10.1 mm, but the seppa dai is inset at roughly 6mm. This one looks like it has been set a couple times and sepoa dai may have been thicker when first made.

 

Jason

[Steve Waszak]

Hi Alex,

 

Well, there could be factors like aesthetics, structural reinforcement, and even just the personal preferences of the person commissioning the tsuba.  In the two pieces I mentioned above, these are both ji-sukashi forms with quite a bit of "air" within/among the metal forming the sukashi walls and the rim.  Perhaps the very thick rims could be seen as a way to "counter" the relative lack of material substance in the guard?  

[Curran]

3 hours ago, ROKUJURO said:

This seems to be a general thing. A thickness between 6 and 5 mm is often seen, but there are rare exceptions up to 10 mm, and many early iron TSUBA of the TÔSHÔ and KACHUSHI type are much thinner.

 

As Jean said above.

In addition to think Ko-tosho, Ko-kinko, and Ko-Katchushi,  you rarely will see a honking large tachi tsuba that will clock in at 10mm. 

In all the years collecting, I have only owned one of those. I should have kept it.

[Alex A]

Saw a real thick tsuba in a plain style, like Tosho. It was on a sword at an arms fair. Convex shape, remember thinking it seemed odd and a bit overkill.

 

One of those things where if you don't usually look for them, you don't seem to come across many.

[Shugyosha]

I've read that tsuba from Sado island tended towards the upper end of the scale thickness wise but I've no figures to back it up. I once had a wakizashi tsuba with a fukurin 9-10mm thick IIRC but the body of the tsuba itself was more slender. 

[kissakai]

Thickest one I have

66 x 67 x 12.5mm. Why so thick?

 

 

[Shugyosha]

One could guess that it had a functional purpose in terms of balancing a long or heavy blade? Is there any suggestion that tsuba were used in fighting to deliver a blow like the knuckle guard on a western blade? Other than functional reasons it has to be purely aesthetic?

[Jesta]

On 8/22/2025 at 5:33 PM, Shugyosha said:

One could guess that it had a functional purpose in terms of balancing a long or heavy blade? Is there any suggestion that tsuba were used in fighting to deliver a blow like the knuckle guard on a western blade? Other than functional reasons it has to be purely aesthetic?

My guess is that if it has a function then it’s to do with balance. A heavy tsuba would bring the center of balance back towards the hands. There are some techniques involving locking tsuba against each other in sword combat, but I’d say it is debatable as to how much they were ever really used. Probably not enough to warrant any redesign of tsuba or we would see this kind of thing more often.