Shuriken Throwing Star From Bicycle Sprocket


Introduction: Shuriken Throwing Star From Bicycle Sprocket

About: Professionally I have been a summer camp counselor, a Draftsman/designer, salesperson, bicycle mechanic, laminate flooring machine mechanic, teacher, and designer of the OP Loftbed. Personally I am a human...

This Instructable will show you how to make a Shuriken (Japanese throwing star) from an old bicycle sprocket.


Step 1: Materials

The only material you need is an old bicycle sprocket.  Front or rear sprockets would work.  Rear sprockets wear out faster, so they are easier to find.  If you do not have your own old sprockets, you can ask at your local bicycle shop.  My local shop had a special trash can full of old metal bicycle parts set aside just for "artists" like me.  Remember to say Thanks.

Step 2: Tools

You will need the following tools:
P.P.E.  Safety Glasses and Gloves
Something to mark with.  I used a Sharpie
Something to cut metal.  I used a hack saw, but a band saw would make it easier.  Just make sure it has a metal cutting blade.
Something to smooth and sharpen after the cuts.  I used a file, but a grinder would really make quick work of it.
Something to hold the sprocket while you cut and file it.  I used a Workmate clamping table, but a table vise would hold better.
Sounds like I need more tools, but that is what it is about, working with what you have.

Step 3: Mark Your Sprocket

The first thing you will notice is that your sprocket looks like it wants to be a throwing star!  Mark your sprocket where you want to make your cuts.  You can freehand it or make a pattern to get your points just right.

Step 4: Cut Off the Non-Shuriken Parts

Use your saw to cut on the lines you made in the previous step.  Do not worry if you are a little off.  You can straighten up your lines in the next step.  Whether you are using a hack saw or power saw, remember to saw with peace.....never saw while mad or angry.  A valuable lesson that I learned from a young student ,in a wood working class I was teaching

Step 5: File to Shape and Sharpen

Use your file or grinder to shape and sharpen the points that you made.  You don't need razor sharp points.

Step 6: Decorate and Enjoy

I usually leave a bunch of my projects unfinished but I was inspired by the contest purple to add a bit of fancy to my Shuriken.  I looked up Japanese symbols for fig  (Another point of the contest purple).  I was pleased that there were more than six, so I could use a different symbol on each of the points.  I painted the symbols with purple finger nail polish.  It makes the shuriken something that you could display with pride.  Instead of just something to throw at an old piece of plywood.

As always,  Have fun and enjoy.

Thanks for reading.



    • Make it Move Contest

      Make it Move Contest
    • Oil Contest

      Oil Contest
    • Casting Contest

      Casting Contest

    We have a be nice policy.
    Please be positive and constructive.




    Dear Charlescranford,

    You are right; it does look like it wants to be a throwing star.

    I've made stuff from old cassette cogs before but had never noticed the similarity until now.

    Despite not having any use for these, I will have to make one.

    Nice Instructable.

    Kind Regards


    2 replies

    Thanks for the comment. I am not sure if anyone has a use for these. I don't even know if they were useful to ninjas. I think you will find that they are great fun to throw at a big piece of cardboard, plywood, or the side of an old shed.
    Just remember to be careful.

    Cool, very cool - - ya didn't just sharpen up the sprocket tips and call it done, ya took some time and trouble - really like this - aaannndd ya get more than one star for ya money.

    Good job - you get my vote.


    1 reply

    Thanks for the comment and vote. Multiple sizes are pretty cool. And remember, you can get old sprockets free at your local bike shop. Free is always good.