Magnetic GoPro Mount - 3D Printed or With CDs

How many times have you failed or not even attempted to set up your GoPro camera in cool places?
Can't use sticky mounts (or don't want to buy a new ones every-time), the support is too dirty/porous/uneven to use suction cups, can't srew/glue onto the precious surface, no edge to use a clamp....
This inscrutable might help you to mount any model of GoPro camera on your clothes, walls, windows, backpack, paraglider, kite, sails , car, boat, motorcycle....

How ?

Magnets!... the strong kind AKA hard-drive magnets

Note this instructable is based out of 3D printed part (thank you Shapeways) - See last step for cheaper version with CD & harddrive magnets.
Anyway back to the magnets:

Get 6 Rare Earth Disc Magnets (Neodymium) 1in Diameter x 1/8 in think ( ~$1 each on ebay or magnet4less.com)
Pick any grade above N40

One single magnet of this dimension has a pulling force of 15lbs: On fabrics, once both mounts (6 magnets) snap together it's almost impossible to separate them with a straight pull. (twist/slide make it a bit easier)

Magnet Physics goodies:

http://www.kjmagnetics.com/blog.asp?p=magnet-grade

http://www.kjmagnetics.com/faq.asp#pulltest

https://www.youtube.com/watch?v=hFAOXdXZ5TM

https://www.youtube.com/watch?v=1TKSfAkWWN0

Disclaimer:
Handling strong Magnets be aware of potential pacemaker malfunction, compass deviation and damage to magnetic media like hard drives....
Neodenium magnets can brake (a bit like cast iron or ceramics). This might expose sharp cutting edges.

Step 1: 3D

Once you have an idea of how strong those small magnet are and the pain is gone from your pinched finger (sorry I forgot to mention this in the disclaimer) get to your favorite 3D software and start designing ...

Couple of things to take in consideration:

Weight/Strength:

Remove material where not needed - drill holes, fillet edges
Use rounded shapes (sharp shapes = high pressure & strain)
Make section/shapes change as progressive as possible
Model an hollow shape with link/reinforcements between surfaces - (think how hard it is to crush a soda can)

Mounting stability:

Consider 3 set of legs for it to be stable (3 point define a plane - 4th or 5th one might not be on it)
try to put opposing magnets as close a possible (the closer they are the stronger they pull)
elevate the center of your bracket so you can mount it on slightly curved surfaces
design the back mount so it covers the biggest area possible but don't make it too big either (surfaces sticking out too much might offer a big leverage and separate more easily)

Drops and crashes:

Rounded edges will prevent the mount to pinch and tear fabrics on impacts
If you think there is a chance for the mount to loose its grip - plan holes to tie up a leach.

Printing restriction:

As always keep in mind the minimum wall thickness and other size of free standing walls.
here are the one from shapeways for Strong and flexible plastics :https://www.shapeways.com/materials/strong-and-flexible-plastic?li=nav

General dimensions:

See pictures for basic mount dimension.
The overall size of this first design is about the size of a CD. (had to fit in a paraglider cell and under wetsuit)

Step 2: Assembly

Glue all magnets with he same orientation (North facing up for instance) for both mounts - test orientation BEFORE bonding.

I'd recommend flexible glue like Goop or 3M 5200 marine (nastiest toughest glue ever)

Epoxy or crazy glue will also work but might resist a bit less to strong impacts.

If weight is not an issue, you can fill up the mounts with glue to make them even more resilient.
In my case I printed extra caps to hide the magnet on the top mount.

Snap both part together and let it dry .This will insure your magnet are correctly oriented and squeeze away the exes of glue in between - remember the close the magnets are the better!)

You will have to reuse the screw and bolt from your regular gopro mount or get another one from Home depot.

Step 3: Using the New Toy!

The magnets will come a bit more easily apart by twisting or sliding them.

Utilization : (tested with low magnetic grade N40)

Dynamic (Shocks &Vibrations) - material up to1/4in thk (tshirt, kite, paraglider, car window...)

Static - material up to 1in thk (table,doors, drywall, ceiling, boat hull...)

On metal (without back mount): might slide little by little with strong repetitive shocks only non-flat vertical surfaces (like certain car's doors) .

And best of All : If it's still not strong enough just stack extra magnets on the back!

Have fun and send me your pics!