# MagnaPlanks™

[![LENgraving](https://cuttle-uploads.imgix.net/9594/800a43bcb1081993e91fb1326830f390381250f7335125497513f65faa53d781.jpg?auto=compress,format&q=80&fit=crop&width=32&height=32&dpr=1)@LENgraving](https://cuttle.xyz/@LENgraving)

Jan 6, 2025 (updated Mar 31)

Public

A simplified remix of [this Nine Plank Puzzle](https://community.glowforge.com/t/nine-planks-puzzle/64410) design posted circa 2020-Jun to the GlowForge community, now improved with optional built-in QR Codes that aid in finding the solution:

## Test Piece

## Instructions:

1.  Specify the actual `magnet diameter` (**_54_** magnets will be needed). Each hole is adjusted by the `kerf` compensation value. Lower kerf = looser magnet fit. A test piece is provided to help ensure you have the proper settings.
    
2.  Indicate whether or not to include the QR (quick read) codes in the solution.
    
3.  Secure the piece to be cut _so that it will_ **_not_** _move_ as the puzzle will be cut in two passes.
    
4.  First pass - top face:
    
    -   Black: Engrave, highest possible lines per inch, power 25%
        
    -   Blue: Score
        
    -   Green: Score
        
    -   Cyan: **Ignore**
        
    -   Red: Cut
        
5.  Second pass - bottom face: flip each plank over about its long axis:
    
    -   Black: Engrave, highest possible lines per inch, power 25%
        
    -   Blue: Score
        
    -   Green: **Ignore**
        
    -   Cyan: Score
        
    -   Red: **Ignore**
        
6.  Remove all pieces and return them to the Top-side up for magnet insertion.
    
7.  Use the stack of magnets as a ram and insert the first polarity (assume north) into all the small squares and slide the stack off the inserted magnet.
    
8.  Turn the magnet stack upside down and insert the opposite polarity into all the small circles.
    

In this variation, there are "only" 47,185,920 ways where the magnets don’t line up.

## Solving:

1.  Orient three planks side-by-side _vertically_ to form the first level.
    
2.  Orient three planks side-by-side **horizontally** to form the second level.
    
3.  Orient three planks side-by-side _vertically_ to form the third level.
    

Between each level, the magnet **polarity** and _orientation_ within each square tile must match that of the tile below it.

![](https://cuttle-uploads.imgix.net/9594/6f7bf68db80a83d4313fd3632f4de262556bd253f8322eab46a109c7fd43b965.jpg?auto=compress,format&q=80&fit=max&width=700&height=1280&dpr=1)

## Solution:

Orient each 3x3 block of the original layout as follows (scan the QR Code to determine where the piece fits in the solution):

![](https://cuttle-uploads.imgix.net/9594/839b469a9ab95d56f61c16f716d3f5a922a397f8f1368e707639e388929f5576.png?auto=compress,format&q=80&fit=max&width=700&height=1280&dpr=1)

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