We did it! 15 participants from all over Japan joined the Yumbo course that I helped to organise with Chio Yamada from Hosei Sansho and Isono-san from Nihon Kenki. Everyone got their skill certifications and can legally operate small construction machines: excavators, bulldozers, and tractor shovels under 3 tons.
The first day was 7 hours of instruction on the mechanics of diesel engines and the working equipment of the machines we are licensed to use – and many revelations about what this certification does not include. The government regulates construction equipment operation and they have a lot of different classes of certification. Want to break something down with a yumbo? That’s a different qualification. This 2-day course is only to excavate, level and load.
Isono-san from Nihon Kenki was a great teacher. Everyone commented how he kept the material engaging through humor and sound effects. He spoke exclusively in Japanese but it was clear and simple. His fleet of construction toys helped to illustrate points. Seven hours of lectures in my second language was exhausting but I learned a lot. Chio did the translations and I know she was more tired than anyone by the end of the day.
Everyone passed their written exam at the end of the lectures. It was full of trick questions, so even with a 60% minimum score to pass, I wonder if Isono-san graded generously. If so, thank you.
The participants in the class came from all over Japan: Okinawa, Nagano, Kanagawa, Tokyo, and all round Chiba. We comprised six nationalities and an age range from 40 to 60. A couple of guys had lots of experience already but needed the Japanese qualification. Some of us were total newbies. It was an excellent mix of people that provided a social opportunity as well as an educational one as we connected our online personas with real life faces.
Day Two focussed on practical skill. We operated a Hitachi ZX30U yumbo under the supervision of Isono-san and learned to drive, turn using the tracks, rotate the body, and to operate the boom arm and bucket to excavate. It was delightful and challenging much like learning to drive a manual transmission car. With more experience, it will all be muscle memory.
Digging requires coordination of three articulated parts on two different joystick controls. There are so many possible ways to do it by combining boom, arm and bucket movement and angles. It’s a nice tangle for the brain.
One thing that must not be overlooked are the safety checks. That means Japanese-style pointing and shouting yoshi! when getting on or off the yumbo, setting positions of the working parts, or moving it in any direction. It really does work to focus attention on the actions and environment, but is also hard to remember. The only thing I ever heard Isono-san being upset about was when we forgot a safety check.
By the end of the day, we had all passed our final practical test:
- Mount the machine hidari yoshi! migi yoshi! ashimoto yoshi! and set the safety lever. yoshi!
- Drive forward (arm at 90 degrees, bucket 40 cm up, blade up) hidari yoshi! migi yoshi ! ushiro yoshi! mae yoshi!
- Excavate a scoop of earth yoshi! and release the dirt to the side yoshi!
- Turn the body 180 degrees counter-clockwise (blade up, boom, arm and bucket folded in) hidari yoshi! migi yoshi ! ushiro yoshi! mae yoshi! hidari yoshi!
- Drive to the starting position (arm at 90 degrees, bucket 40 cm up, blade up) using the controls in reverse hidari yoshi! migi yoshi ! ushiro yoshi! mae yoshi!
- Turn the body 180 degrees counter-clockwise (blade up, boom arm and bucket folded in) hidari yoshi! migi yoshi ! ushiro yoshi! mae yoshi! hidari yoshi!
- Park the machine (blade down, bucket flat on the ground) yoshi!
- Release the safety lever, safely exit the machine hidari yoshi! migi yoshi! ashimoto yoshi! and salute the instructor.
YOSHI!
