Checking shinai

[Anorymous]

I have noticed that, on new shinai, there's a sticker that says "Make sure to check shinai before and after each use." (There's more, but I didn't bother to translate any.) I used to pay little heed to that, only checking my shinai when I disassembled them, but now I'm thinking of doing quick check-ups every practice or so. Thing is, I'm not really sure what to look for. So, I was wondering if there were any specifics to checking shinai without disassembling them, things to look for, tricks for making faults more obvious etc.

Thanks in advance.

(I apologise if it's been asked before; I checked the last two years and there wasn't anything on that.)

[ender84567]

You should be checking it periodically to make sure its safe. I always check shinai before practice, and probably a half dozen times during practice. some of the things to look for are: large splinters, the beginning of a splinter, broken/loose nakayui, broken/loose tsuru, hole in sakigawa, cracks in take.

[rfoxmich]

I entered the google phrase Check Shinai and get among others:
http://www.bestkendo.com/SHINAI.html
http://www.kendo-guide.com/choose_a_shinai.html
http://www.shinai.org/housemef/shinaimaint/shinaimaint.html
http://www.kendoniagara.com/ShinaiMaintenance101.pdf

and so on. I would be really concerned that you have not yet been instructed to check/maintain your shinai.

[ender84567]

Best kendo is the only one of those that show what a splinter and a crack looks like, I disagree with their 'hot glue trick' as well as the nakayui leather will stretch and that is what makes it loose, not the knot.

[JByrd]

What ender said.

Note that a crack in a stave may not be readily apparent when inspecting a fully assembled shinai. At least once a month I untie and remove the tsuru and nakayui, and slide off the sakigawa, leaving the handle on. That allows me to separate the staves and inspect each one thoroughly. I bend each stave in both directions (toward the shinai, and away from it) while looking at the side for any cracks to open up. More than once I have found cracks using that method in shinai that appeared OK from an external inspection.

I recommend routine partial disassembly to all my students since it is quick, reliable, and encourages them to practice retying their tsuru and nakayui. One of my peeves is people using shinai with very loose nakayui. If the nakayui is not tight, the shinai staves do not flex together properly, and the force of impact is unequally distributed, raising the chance of failure.

[ender84567]

Cracks on the inside are usually detectable by how a shinai 'behaves' it tends to just not bend/feel right. I usually put a shinai down when something feels 'off' about it and use another one that I know is good, usually later inspection of the first one reveals a cracked take on the inside). Unfortunately that kind of sense is only developed thru practicing kendo.

[Anorymous]

I would be really concerned that you have not yet been instructed to check/maintain your shinai.

I do know how to maintain my shinai, thank you very much. Thing is, I don't do that more than once per month, so I was looking for a way to check them without disassembling. The information I was looking for was in your first link, so thank you for that (and ender for pointing it out).

That said, JByrd's "partial disassembly" suggestion looks mighty interesting; it saves fully half of the hassle. I think I'll start making it a routine.

[ender84567]

Ron was mentioning the fact that you only do it once a month is concerning.

[ShinKenshi]

Thing is, I don't do that more than once per month, so I was looking for a way to check them without disassembling.You should be checking it much more often than that. A good habit to get into is at least give them a cursory inspection after each practice and if you see something that isn't right, set it aside when you get home to tend to when you can.

[CauseImSmaller]

Hey guys, I happened to look at the shinai maintenance links posted above. If my shinai is waxed on the inside, is oil necessary?

Note: Shinai came waxed.

[Anorymous]

Ron was mentioning the fact that you only do it once a month is concerning.I fail to see where he mentioned that.

Anyway, I'll admit that it was a mistake to not adopt that "cursory inspection" earlier. As far as the maintenance is concerned, though, I don't think that more than once per month will make a difference. Of the three shinai that I've had to "retire" so far, not one of them had any "faults" (splinters, cracks and the like). Maybe the humidity here does them good.

CIM: Were I you, I'd avoid sanding the inside (to allow the wax to remain) but I'd definitely sand, and apply oil to, the outside of the shinai. I don't have much more than my gut feeling about that, though.

[jd111]

i used to sand the edges of shinais before use, but i dont anymore, and they rarely splinter or crack. it could be that im using better quality shinai than before, but i dont do the whole ritual or sanding and oiling with new shinais anymore.

I usually wait untill a fault develops before i oil or sand. that way the balance is not affected

[ShinKenshi]

I fail to see where he mentioned that.Checking your shinai after each practice to see if any splinters or cracks have developed is a relatively normal and commonly taught to beginners from the onset. Coming from that point of view, Ron was concerned that you hadn't been taught that given you only check yours once a month.


Anyway, I'll admit that it was a mistake to not adopt that "cursory inspection" earlier. As far as the maintenance is concerned, though, I don't think that more than once per month will make a difference. Of the three shinai that I've had to "retire" so far, not one of them had any "faults" (splinters, cracks and the like). Maybe the humidity here does them good.Could be but at the same time, in the long run, quick checks much more often will save many slats from cracks since you'll catch any splintering and will be able to mend them before they reach the point of no return. Not to mention it'll also save your wallet from extra shinai expenses.

[ShinKenshi]

i used to sand the edges of shinais before use, but i dont anymore, and they rarely splinter or crack. it could be that im using better quality shinai than before, but i dont do the whole ritual or sanding and oiling with new shinais anymore.

I usually wait untill a fault develops before i oil or sand. that way the balance is not affectedYou can't really attribute the lack of sanding and pre-treatment to a drop in cracks and splinters in your shinai since it could also be the result of overall better cutting form and a lack of right arm bludgeoning. At the very least I feel it is better to round the edges of the slats so they don't get stuck. I've had several last at least a year from regular checks, sanding the edges, and applying oil after each fix.

[jd111]

You can't really attribute the lack of sanding and pre-treatment to a drop in cracks and splinters in your shinai since it could also be the result of overall better cutting form and a lack of right arm bludgeoning. At the very least I feel it is better to round the edges of the slats so they don't get stuck. I've had several last at least a year from regular checks, sanding the edges, and applying oil after each fix.
Im more so saying that i dont think its entirely nessecary, and that some people may get carried away with sanding and oiling new shinais, rather than it being a factor in my shinais not breaking

and to be honest (+ modest), my cuts are alot better this year :D

i decided at the start of 2010, that i wouldn't oil shinais initially, and its been about the same as when i did oil them

i am an absolute stickler when it comes to my equipment though, and agree with all above posts, especially the second one in the thread. I dont think anything more needed to be said TBH

[Anorymous]

Checking your shinai after each practice to see if any splinters or cracks have developed is a relatively normal and commonly taught to beginners from the onset. Coming from that point of view, Ron was concerned that you hadn't been taught that given you only check yours once a month.

Ah! Yes, I can see that now. Still, I do think that his post was ambiguous.

Anyway, the frequent "five-minute checks" were usually done by our sensei, before practice, while we were stretching and warming up. Oddly, we were never taught how to do that; I had indeed noticed him pushing the slats together to check the edges, and trying to move the nakayui up/down to see if it's snug, but I wanted to see if there was anything more to it than that.
This, however, was in my previous doujou; nowadays my shinai had gone unchecked. Andy's post in the myopia discussion got me worried. Thus, I wanted to know what to look for myself.

Also, ShinKenshi: I've already agreed that I should be checking them often--from the first post, in fact. You don't need to repeat that point any more.

[Anonymous]

I wanted to see if there was anything more to it than that.


Shinai aren't exactly the most complicated pieces of equipment on the planet, just visually inspect them before and during practice to see if any problems are starting to pop up.