This is really just a combination of two good ideas from other people: Using scrabble tiles as refrigerator magnets and l33t scrabble tiles. That said, I get lots of positive comments on these magnets, so I'm rather proud of them.
It is the middle of the night and you have awakened hungry. The sound of your stomach growling echoes in your humid room. As tired as you are, you know the munchy demons will not let you sleep until you sate your desire so you throw off your blanket and get out of bed.
> exit door
You exit your bedroom through the door.
It is pitch black. You are likely to be eaten by a grue.
The sound of clapping activates a relay and turns on the light.
You stand in your kitchen in front of the refrigerator. Attached to the door is a cryptic message written in strange, green runes etched on black tiles. It reads:
J00 R N00B PH34R MY L33T SK1LZ
Step 1: Materials and Tools
This is a list of the materials and tools I used to complete make my magnets. This isn't the cheapest way to go, but it worked out pretty well for me. Prices are listed without shipping costs factored in.
L33T Tiles - $3 - Of course, you can use Scrabble tiles instead, but then what is leet about that? These tiles come as a set of 103, and are a great deal. These are on closeout right now, so buy them while they last!
ZD2 Disk Neodymium Magnets - $22 - The most expensive part of this project. These magnets are plenty strong to use in this project, and you can probably get away with using cheaper, weaker magnets if you want. You want to get about 20 more than the number of tiles you want to convert to magnets - I broke a few playing with them, and the spare magnets come in handy later in the project.
Adhesive - $6 - I used these little adhesive dots and they worked great. They were a little tedious to use, but I think the results were cleaner than if I had used epoxy. Really though, any glue capable of adhering to metal and plastic would work alright here.
Plasti Dip - ~$6 - You can get this from Home Depot, Lowe's, or any home and garden store. Get black if you can, it blends in with the black tiles and looks great.
A handful of bolts - ~$2 - These are going to be used to create a handle when dipping your tiles in the plasti dip. I got 20 and did 5 batches. You probably have something around the house to use.
A cookie pan or similar sheet of metal - This is for sticking magnets to while things dry.
A small shallow resealable container - This will pretty much end up destroyed. A disposable sandwich container is perfect for this.
A black refrigerator - $400+ - These look great on a black fridge, but I wouldn't go out and buy one just for this project. I needed a new fridge anyway, so I bought one that matched my magnets...
Total cost for me (minus the fridge) was $36 + shipping. In the end I got a very professional looking product, so I don't mind that they cost a bit. There's a lot of ways to cut down on the cost. Using non-rare earth magnets would save a bundle, and you could probably skip the plasti dip if you did that.
Step 2: Warnings
The magnets for this project are fairly weak as far as neodymium go, but some care should be taken when handling.
DONT EAT THEM - This warning includes children, as should be obvious.
Don't get them near a pacemaker.
Don't let them snap together - you can easily break them.
Don't try to drill or cut them, you'll end up with a bunch of magnetic dust.
Don't heat them... they'll lose their magnetic properties.
Don't burn them... they produce toxic fumes.
Also, the plasti dip is pretty foul, I recommend using it in a ventilated area.
Step 3: Glue Magnets to Tiles
... or glue the tiles to the magnets, whichever floats your boat.
If you're using the adhesive dots, all I did was peel off the backing on every other dot and attach magnets to the adhesive. Then I pulled the magnets up and attached them to tiles. If you make sure that the same pole is always pointing up, your magnets won't attract to each other, and you can do these in batches. It goes a lot quicker than doing one at a time.
If you're using glue, make sure to space the tiles far enough part while the glue dries... Otherwise you'll invariably glue one magnet to another... and that isn't easy to fix.
Let your glue dry completely before moving on to the next step.
Step 4: Safety Coating the Magnets
You can stop at step 3, but I chose to coat the magnets with plasti dip for three reasons:
1) The magnets are brittle and easy to break if you drop them.
2) I didn't want to scratch up the surface of my new refrigerator.
3) The plasti dip acts as a secondary adhesive, helping to hold the magnets on. In theory at least.
If you choose to do this step, please see this tutorial first: http://www.kjmagnetics.com/rubbercoat.asp. It does a good job explaining the general procedure I used.
1) Pour your plasti dip into a shallow plastic container. A metal one would be foolish indeed. Don't use all of it at a time, since you'll probably do several batches.
2) Stick the tile to the broad side of the bolt - the magnet won't be strong enough to hold the tile and bolt together by itself, so...
3) Stick a spare magnet to the opposite end of the bolt. The two magnetic fields will attract each other, and your bolt handle should be pretty sturdy.
4) Dip the magnet side of the tile into your plasti dip. Go slowly and try to cover up half of the sides of the tile. Spin the tile around to get all the crevices. Avoid air bubbles.
5) Turn the tile right side up and attach to your sheet of metal to dry. The plasti dip will look pretty thick, but don't fret, when it dries the viscosity will make the rubber coating form fit around the magnet and tile. If you're worried, do just one first to see what I mean.
6) Allow 3-4 hours to dry before taking the tiles off the bolts. I only needed one coat, but you may want to do some touch ups on any that had an air bubble in them.
Step 5: Enjoy
All done! Attach these to the fridge and let your drunken friends spell their names and dirty words.
This has been my first instructable, please post constructive criticism for what I can do better in the future... and thank you for putting up with my crappy iPhone pics.