I picked up a 6' rod of 3/16th's steel at my local hardware store. That sounds like a lot but I didn't have to trim any of it.
I got some string from the same store.
Total Cost: about $8
I just used a large pair of channel lock pliers and my hands to make all my bends. No special tools required.
You have to use some caution making the bends as if you make a bend too sharp you're going to have a pretty rough time getting it straightened back out.
Here it is in full glory:
|The Under The Door Tool (MULE)|
|From Top of the Lever Catch to the Bottom of the Curve 42"|
|Proof it's actually 42"|
|From shaft to handle 14"|
|4.5" for the handle.|
|Just over 6" for the top|
|End of the Rope 5'|
Here's 3 videos of it in use. I've included the fail videos to dispel the theory that this is magic and everyone gets it on the first try. I hate videos that only show things working, you learn nothing from things working, you learn from things not working. It's not a complicated tool, but there are some caveats.
In this video you see what happens when your rope isn't at the point closest to the door, hence the redesign needed for the loop where the rope connects to more of a triangle.