With temperatures dropping into single digits overnight we put the snow wall up yesterday. It changes the way things feel and I miss the open vista from the shajo, but it makes a big difference. I thought I’d post something about how it’s set up.
The wall itself is composed of panels that slide on tracks built into the ceiling of the shajo. Each panel has a steel frame faced with aluminium on both sides and filled with insulation. They fit together like tongue-and-groove flooring. After all the panels are in place we stuff foam-rubber in the cracks to enhance the insulation and eliminate places where wind and snow could blow in (you can see some of that long the bottom).
Each panel has a double-pane window hinged on the bottom and latched at the top. When you want to shoot, usually the first move of the Hokkaido Hassetsu is to go forward, open the window, then go back to the honza and begin as usual. Then after yudaoshi you close it. The window panes have a red or orange vertical stripe in the middle of the glass. The reason is two-fold: with the wall up, people in the kanteki area can’t see if someone is shooting or not, but if the red stripe is visible, the window is closed, so it’s safe to go collect the arrows. We also have an audible alarm and flashing lights that that are automatically activated when kanteki door is open, but it’s always good to check for yourself. The other reason is from the other side, so someone doesn’t accidentally go ahead and shoot thinking the window is open!
Since the window glass hinges down, that leaves the glass exposed if a shot goes way low. Sometimes there are students who are still quite short, so whom this is a bit of a risk, and we have wooden panels that can fit over the glass to protect it. Using those is left to the discretion of the kyudoka. The tacit understanding is that if you break the glass, you pay to replace it.
When you open the window, there’s a layer of polyethylene with an opening cut out. The idea is to make the windows large enough that the chance of hitting the frame is next to zero no matter who’s shooting, yet keep the opening small so that there won’t be a lot of snow blown in. The plastic is soft enough that an arrow will go harmlessly through. We have two shapes. The diamond one is normal, but there are a couple that have vertical, rectangular openings. People who are taller or shorter than normal use those. The openings are reinforced with waterproof packaging tape. If an arrow glances off this it generally won’t hit but it won’t fly wildly, either. What you absolutely don’t want to do in Hokkaido winter is lose an arrow in the snow! We have a metal detector for that, but if the shaft is carbon or bamboo only the yajiri will set it off, so it can take a while to find one.
So that’s all there is to it. The wall protects the floor (and us) from wind and snow, lets us run heaters in the shajo during practice times, and helps maintain a more constant temperature for the bows and arrows stored in the dojo even when the outside temperature drops to -20 or -30 in February.
Speaking of which, I sent in the deposit for the bows. The yumi-shi says that he has the higo and inner/outer bamboo all picked out and will start making the bows in mid-November.
LATER I forgot to mention that the azuchi is left as usual, completely exposed. Since the shajo faces west and the prevailing winds during winter are also from the west or northwest (Siberia), snow doesn’t usually blow onto the targets. But what does happen is that the azuchi can freeze solid as a rock, a potential disaster for bamboo arrows and not so good for any other kind. So what we do in late autumn is dig out the sand for about half a meter behind and around each target, mix the sand with calcium chloride pellets (from the hardware store) and then put the sand back. The CaCl2 does a good job at keeping the water in the sand from freezing.
As for the yamichi, that’s exposed, too, and since we do get 1-2 meters of snow, the staff use a heavy snow blower every now and then to keep it from getting in the way.