Wooden Coin Sorting Machine (Runs On Gravity)

Picture of Wooden Coin Sorting Machine (Runs On Gravity)

Tired of sorting coins manually? Coin sorting is a tiresome job. Let's make a wooden coin separator out of common materials! The sorter uses plain old gravity to separate the coins to their designated container. You know what that means! No more batteries!

What Made Me Build This?
Every time I go home from school, my pocket always gets full of coins. Once I arrive at my bedroom, I sort the coins to my 3 huge piggy banks. It's pretty tiresome thinking that I do this on a daily basis. So I thought of building a simple contraption that sorts coins by using gravity. The idea is pretty old, BTW.

Why Are There Only 3 Compartments?
There are six Philippine coins: 10 php, 5 php, 1 php, 25c, 10c, 5c. In my bedroom the 10 & 5 peso coins share the same piggy bank, both coins are the same in size by the way. The 1 peso coins has it's own piggy bank since it's the coin that has the highest quantity & it's pretty common. The 25, 10 & 5 centavo (cent) coins also share the same piggy bank since I barely get those.

Full Video Demo + Explanation:

Demo Video:


Remove these adsRemove these ads by Signing Up

Step 1: Tools & Materials

Picture of Tools & Materials
I didn't spend anything since I have all the tools, parts & materials in our backyard (inventory).

Parts & Materials:
- MDF Material (your choice of wood)
- Bendy Straws
- 3.5mm Screws 
- Foam Board
- Super Glue

Tools & Equipment:
- 3.5mm & 6mm Drill Bit
- Jigsaw (Hacksaw)
- Right Angle Ruler
- 48" Metal Ruler
- Electric Sander
- Eye Protection
- Portable Drill
- Gas Mask
1-40 of 46Next »
Housedog1 year ago

It's very cool, but I don't quite understand how the straws sort the coins!

Maybe I'm having a bad brain day, but I don't get it.

If the straws were cut in half, and then had different size slits cut in them, it would make sense to me, but it doesn't look like that.

Can someone help me comprehend this please?

BTrey Housedog1 year ago

I don't the think the explanation is at all clear until you understand how it works. Then, magically, it suddenly seems easy and clear. The sorter works based on the height of the coin. As the coin rolls, the top of it leans against the higher straw but it can't fall because that straw us there. Just before the coin reaches the wall, there is enough gap for a coin of the right size to fall to the side. So the coin just rolls until there is a gap larger than the coin is tall between the two straws, then it falls.

ibwebb BTrey1 year ago

Thank you! I was in the same boat. I read it twice and still though I was missing something. Glad you answered! lol

Housedog BTrey1 year ago

Thank you.

Sometimes, some things just don't click!

Here is a picture from the author's instructable.

There is a few mm of space between the top straw and the wood. When you insert a coin, it will roll along the bottom straw. The gap between the two straws increases as the coin rolls further along. Small coins will fall into the first box because it will fall through the gap between the two straws. Bigger coins can't fit through that gap, so they will continue to roll along until they reach a gap between the straws big enough to allow the coin to fall through. I hope this makes sense.

Did you watch the author's demo video? He explains is pretty clearly.

Watch this video too.

I watched the authors video several times - it's too far away for me to see what is going on. Thank you for the lego video. It looks magical and unfathomable as well! Maybe I've had a minor stroke or something!

Remember those 3d pics you had to stare at while relaxing your vision, then all of a sudden it turned 3d? This seems to be analagous to that. Sometimes they would pop right into your perception, other times you could stare for minutes and still not see it!

Thanks for trying to help me.

Mr AbAk4 months ago
Nice Ible ...
builder61005 months ago
That is an excellent idea!! I will be making this next weekend because I need to find time to run to the store for the materials. I'm just wondering what size mdf you used and what kind of wood you used?
thedugsh6 months ago
made it from the things i found inside my room. :D
Great work.. thanks!
pompogi8 months ago

very ingenius!!! mabuhay ka!! kabayan!! thats filipino ingenuity at its finest!!

pompogi8 months ago

magkano? it will be a good and fun way to teach my kids about saving money!

pucksurfer10 months ago

this is so cool

mpintovsj1 year ago

Genial ! , muy buen proyecto.

I like it but i dont understand how its being sorted.
Maroga1 year ago

One question, would I be able to replace the straws with wood? That way it will look way cool!!

ASCAS (author)  Maroga1 year ago

Yup! It's up to you, it's your project afterall.

Maroga ASCAS1 year ago

Thanks mate!! Will it do the trick? Will I get the same sorting results?

ASCAS (author)  Maroga1 year ago

Yup, it actually depends on your positioning, but adding straws are much easier since you don't have to cut thin pieces of wood.

jmacangus1 year ago

I would look nicer if you carved out the coin sorting parth out of wood.

ASCAS (author)  jmacangus1 year ago

Yup! :)

cool dude, added to my favorites

rich_j_l1 year ago
I've tried this with a few variations and some British coins are so similar that I've not been able to master this so far...shame as it's really smart!
psychotron1 year ago

Nice Job!

jonobugs1 year ago

I had a bit of trouble understanding at first, too. I think the problem in understanding is the thinking that there is a chance that smaller coins might continue on but I think the trick is that the straws are positioned so that the coins are leaning as they roll and will easily fall as soon as the gap between the upper and lower straw is large enough. I think this is a great idea, but it might be better if there was some sort of funnel at the top of the sorter so that you could throw in a small handful of coins at once and not one at a time. Another addition might be to make the coins stack once they are sorted. I think you could do that by narrowing each compartment until they are the size of the coins. Very cool instructable!

iOskr1 year ago

Simple and amazing!!! Thanks for sharing

tim_n1 year ago

very clever - I was trying to work out at the start how the mechanism would work. It turns out, there isn't anything mechanical at all. I imagine the coins need to be on one side of the bottom straw (furthest to the back) or it won't work as it'll be leaning against the back of the box and will therefore drop into the last hole.

Laral1 year ago

Interesting project. I would suggest that you re-word your explanation of the sorting mechanism since it is the heart of the machine and people, including myself, could not understand your overly brief explanation. Your video does little to further explain it. The lego video, linked to by King of Clubs,, shows very clearly how it works. The upper straw segments are positioned away from the back wall so the coin tilts to one side as it rolls. You don't make this clear at all. The height of the first upper straw segment is made just high enough to allow the smallest coin to fall sideways into the first chamber before it reaches the entrance to the second chamber and so on down the line.

Arghus1 year ago

i built it on the moon but the gravity being lower than on earth where i suppose you built your sorter, it just doesn't work for me..

Hecate1 year ago

It's a great idea!

cosca1 year ago

I love these coin sorting machines!

ASCAS (author)  mikeasaurus1 year ago

I've also been amazed with coin sorters ever since I was a kid. Now, I've finally built one. Next stop... ATM at home - Bill sorting machine! :D

Great idea and great instructable!!! Keep up the good work!

(Also, I always enjoy seeing fellow Pinoys on the internet. :D)

Loved it :). Just brilliant :)

maliboo1 year ago

you have my vote


mluttrell1 year ago
Thanks! Clever way to sort. Great Instructable!
azharz1 year ago

Nice one.

BayRatt1 year ago

Well done! That's so neat!


1-40 of 46Next »