Picture of Brass Bolt Puzzle
Bolt Puzzle.jpg
Bolt Puzzle Cross Section.jpg

This puzzle you can either 3D print or make using some M16 & M8 Brass nuts and bolts.

The origional idea for this puzzle is based on a puzzle from "homemade puzzles" http://homepage.ntlworld.com/bruce.viney/Bolt%20P...


3D files are available at Thingiverse or GrabCad

How it works

The aim is to get the washer off the bolt. The idea is the magnet is glued into the top section of the main bolt with epoxy. Which will hold the steel rod in place when the assembly is together. To open the puzzle you need to slam the base on a hard surface dislodging the rod and allowing you to remove the other parts of the puzzle so you can remove the washer.

Step 1: What you will need

Picture of What you will need
  • M16 x 60mm Brass Bolt (ebay)
  • M16 Brass Nut (ebay)
  • M16 Brass Washer (ebay)
  • M8 x 60mm Threaded Rod (ebay)
  • 2 x M8 Nuts (ebay)
  • 3.5mm x 24mm Steel rod (I used a nail that was about 3.5mm)
  • 4mm x 2mm round rare earth magnet (not shown) (ebay)


  • Drill press or hand drill
  • Center punch
  • 2mm, 4mm, 4.5mm, 8mm drill bits
  • Hand files
  • Hacksaw
plop5091 year ago

this would be sooooo cool to get my friend back for his

puzzle a few weeks ago.

bobes360 made it!1 year ago

It does not look so nice and shiny but according to your instructable I MADE IT! Thank you for posting .. I gave it to many of my friends but noone solved it.

pitty (author)  bobes3601 year ago

Nice, maybe you could shine it up a bit on a buffing wheel if you have access one.

bobes360 pitty1 year ago
Yeah that's a good idea - I will certainly try it.
karossii1 year ago

very nice. A video would do wonders...

I agree a video would be great at demonstrating this!

kracken421 year ago

This'll be great for giving my friends migranes.

willymagoo1 year ago


Cut the bolt where the nut goes. Drill the parallel holes in the top and bottom half. Glue the magnet into the top half, put the rod into the bottom part. Put all together and drill the cross hole. Then just put the cross bolts in.

The cut can't be seen when the puzzle is together as it's covered by the bolt.

fzumrk1 year ago

Regarding your plan to braze the hole after installing the rod and magnet, heating up a rare earth magnet will de-magnitize it. This would also probably melt the epoxy used to secure the magnet. You could put a slight taper on a piece of brass rod and drive that into the hole instead. Or you could probably fill the hole with JB weld if you used galvanized hardware and not have it be noticed.

Greetings, So that is what happened to My pick up tool. I never could even re -magnitize it using My H/F magnitizer - de - magnitizer. Thank You. ~(:-})={

Delaney fzumrk1 year ago

well they could put the steel rod in braze it and using plastic tweezers or something similar to insert the magnet afterwards through the side hole.

pitty (author)  Delaney1 year ago

That was just what I was thinking.

Isn't JB weld epoxy too? Metal dust suspended in epoxy?

MrE1 year ago

Simply Fantastical good sir.

Ryan2718281 year ago

Well done, sir, well done!

pitty (author) 1 year ago

Tthanks for the encouraging comments guys.

Good instructable and an improvement on the one in the link you have provided.

aborashid1 year ago
Very nice finishing
jmwells1 year ago
I've seen this puzzle made as your friend suggested. It is a bit of work, but the finished product looks a bit better. Also the brazed portion is a bit harder than the bolt. It would seem that it would hold up better, and not be dinged or flattened.