Build Your Own: Chiishi

Hello!

In an effort to make karate training even more accessible & affordable for everyone, we'll be showing our readers how to build their own training tools. This article is about building your own chiishi!

I've seen basic 10lb chiishi advertised for as much as $60 each. I've even seen some fancier models advertised for over $100! I don't know about you, but as a teacher working my way through grad school I certainly don't have that kind of money. Plus, it's difficult to find appropriate weights. Some students may need lighter and others may prefer heavier chiishi.

If you have $10 and some elbow grease, you can make your own chiishi customized to your specifications.

All you need are:

-Concrete mix (found at most hardware stores)

-Dowels (cut to your desired length)

-A few nails or screws per dowel

-Stirring tool

-Chiishi moulds (we used Dollar Store mixing bowls, a deep pie tin, & a small bucket)

-Cooking spray

-Water

-Drill or hammer

Directions

1. Insert the screws or nails into one end of your dowel sticking out of the side. This will provide additional support to eliminate the risk of your dowel sliding out of the concrete onto your toes while training. 

When choosing a dowel, choose a wider one. Not only will this provide additional strength to the chiishi, but it will make your training more realistic. Gripping the chiishi should mimic the gripping we do when we grab an opponent's clothing or wrist. Too thin and you're missing this training point.

2. Spray your mould with cooking spray. This will allow the concrete to pull out smoothly when it's set.

3. Mix the concrete and water in your mould. I prefer using slightly less water than concrete but nearly a 50/50 ratio. 

4. Slide the nail-end of the dowel into the concrete mixture. If the concrete was properly mixed it should be solid enough to hold the dowel up straight. 

5. Wait overnight for it to set and then voila! You're one step closer to your own hojo undo collection. You'll likely have plenty of concrete mix leftover and your moulds are reusable. Experiment with using smaller or larger moulds to find a weight that suits you.

When adjusting sizes, it's better to have a mould that is wide but thin, like a pie, rather than compact. By moving the weight out you will increase the amount of inertia due to the change in the chiishi's center of gravity. This increases the force needed for you to stabilize the chiishi's weight & will activate more muscles, even with a lighter weight. You'll decrease the amount of work needed by pulling the weight in; think about figure skaters pulling their arms in for a spin. Train smarter for a better workout!