How to Make an Indestructible Money Box




About: To see more of my work you are welcome to follow me on Instagram @cam_de_burgh

Money boxes are a great way for kids to save money for a special purpose.

Unfortunately we can get tempted to spend the money on other things before we have reached our goal. That's when this money box is useful.

Most money boxes have an opening that allows us to simply take out the money whenever we want. The sad thing about this is that it usually means then box never gets full.

Made from chequer-plate steel, this money box is easy to put coins into, but it's really really hard to make withdrawals.

Please note that you might need to use a grinder or oxy to get the money out, so perhaps it's only for coins, not banknotes.

Step 1: What You Will Need

Steel plate. Whatever you can lay your hands on. It should be light enough to work on, but heavy enough to weld easily.
Measuring and marking gear. Tape and chalk.
Something to cut with. I used an angle grinder.
An angle grinder for grinding.
A welder. I'm lucky enough to have a MIG. It's fantastic.
A hammer also might come in handy.

Step 2: What to Do

To make a cube you only need six square sides. If you have enough steel you can cut out a single shape that can be folded to make a cube. That will save some cutting and welding.

  • Mark out the shapes you need on the steel.
  • Cut the steel.
  • Grind the edges so they weld nicely.
  • Assemble the cube and tack it together.
  • Weld all joints.
  • Clean up the welds with a grinder.
  • Cut a slot to drop coins through. Position it where coins won't easily come out.
  • My steel was a bit rusty so I cleaned it a bit wit a wire brush.
Check out this video to see how I did it...

Step 3: Other Possibilities

As you can see I've made a few different shapes.
The smaller cube has been opened twice. You can see where I have patched it.

I hope you have enjoyed this Instructable.



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    19 Discussions


    3 years ago on Introduction

    Nice! I like your examples, especially the heart-shaped box! Have you ever been asked to cut one open to retrieve the money inside?

    2 replies

    Reply 3 years ago

    I just used the angle grinder to open the money boxes. Then weld a patch over the hole. The patches actually look quite cool.
    We did learn that heat isn't good for plastic bank notes though.


    Reply 2 years ago

    If you were making a money box out of a milo tin and wanted to use it upside down so that the lid could be used to get the money out of, how would you make the slot in the top (the bottom of the tin) to drop the money in?


    3 years ago on Introduction

    I am trying to get some ideas on a money drop box safe for a business, the door has got me allittle an really cant find a decent lock

    1 reply

    Reply 3 years ago on Introduction

    I know how you feel. You will notice I did not include any door at all on mine. Very secure, but not very convenient.

    inventor scout

    4 years ago

    I might have missed it, but how does one open the box?


    4 years ago on Introduction

    I want to buy one right now, if anybody makes these and let me know. I seriously seriously want this.

    3 replies

    Reply 4 years ago on Introduction

    That's pretty big! Enough to hold about a million bucks. I'll make one for you if you are in Australia, but if you are elsewhere, freight would be excessive.

    Great, i just love this ,i bet it makes quite a noise when messed with.
    Was just thinking that large diameter pipe ( square or round ) might work also.

    1 reply

    Reply 7 years ago on Introduction

    Thanks. I'm glad you like it.
    Good idea. Square or circular hollow section would be easy to use for one of these. You could make them as long as you liked.

    lolz, sad thing is that i use a 10cm *10cm * 10cm 3mm metal cube like this for a place to keep coins, the only diff is there is no lid on one side.

    i think yours is neater, i only welded on the inside of the box.

    how did you do the curves on the heart? is it one piece, it is very neat
    and the edge of the box with the coin slot?

    if i may add one point is. i think it would b nice to have it like a puzzle cube or soemthing, and some how have a solinoid holding one plate and it caould only b opend by someone who knows how it works putting a current in it, even a pattern with an adrino?
    your oppinion?

    1 reply

    Thanks for your comments.
    The heart is four pieces. I made the curves by tacking the edge piece to the heart shape and hammering it into shape progressively around the shape.
    I like the idea of the puzzle to open. I'll be pondering that one.

    Phil B

    7 years ago on Introduction

    65 years ago when I was a baby my aunt gave me a nice porcelain piggy bank. I eventually was able to shake all coins out of it without breaking it. Would you consider making this with an opening for easier removal of the coins?

    Nice job.

    2 replies
    cammersPhil B

    Reply 7 years ago on Introduction

    Thanks Phil. I could do that, but really my goal was to make something that was impossible to beat.
    Perhaps a determined child could shake some coins out of this one. I suspect it would be easier if the box was half full.
    Thankfully steel is more forgiving that porcelain; if you cut it open you can fix it.

    Mr. E Meatcammers

    Reply 7 years ago on Introduction

    My Grandfather used to keep all his change in a pottery piggybank with only a coin slot. Each summer my brother and I stayed with my grandparents and we used to get to fish all the coins out of it to use as spending money for the summer. We inserted a butter knife an jiggled it until a coin aligned with the slot. It usually took a while to empty and kept us out of the grandparents hair for a while!