The Useless Box
 

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Matthew Knoebel
Made by request for Matthew Knoebel, July, 2013.
 
Matthew Knoebel
Here's Matt in 2012 at Children's Hospital of PA.
When these two pictures were taken, Matt was suffering from Leukemia.

 
Useless Box
The useless box, before and after. Obviously they're two different boxes, but you get the idea.


Inside box
The inside. The motor is a 5 RPM 12V motor running on two 9 volt batteries in parallel.


Making the useless box:
 
Concept
Here is the concept...
Finished
...and this is the finished product.

This was going to be one of those projects that takes a few hours and works the first time. It ended
up taking many hours of tinkering and fine tuning of the layout, and several prototypes.
 

1st box

This was the first version. This was a nice box I bought for $6. I didn't want to cut the lid so I put the switch on the front. The lid opened and the arm came out and toggled the switch, but I didn't like the way it looked. Now the box is wrecked because there is a hole drilled in the front. We went to a craft store and got some different boxes for 88 cents each.


 
cardboard prototype
All subsequent prototype boxes were made out of cardboard.
 
prototype in wooden box
The cardboard prototype in the wooden box. The arm
was controlled by touching the motor wires to a battery.
working version
The working version with the cutoff switch.
The board slides into two slots added to the box.

 
DPDT switch connections
DPDT switch connections
This is the way the D.P.D.T. switch is wired. I drew a diagram so I wouldn't confuse myself.

 
Cutoff Switch
The cutoff switch with the "arm" against it, in the "off" position. (Normally closed type)

 
How it works:
When the switch is turned on the motor is energized. The arm comes out and turns the switch "off."  The "off" position
reverses the voltage to the motor and the motor runs backwards. The motor stops when the arm depresses the cutoff switch.
NOTE: the cutoff switch is the Normally Closed (NC) type. When the button is depressed the circuit is open.
 

 
Action figure
throwing the switch
 
 

We bought this action figure at the dollar
store so we could use his arm.

His hand was supposed to come out and turn off the switch.

 
 
 
closed hand
 
open hand
 
His hand was placed in boiling water to make it open.   While his hand was in the boiling water,  he
confessed to being a heretic, among other things.
 
mounted hand

It worked! Then it snagged on the little door on the way
back in and almost broke it, so the idea was shelved.


 
Inside View

Inside the completed box. Everything is removable. The batteries are held in with Velcro. A bit of black spray paint keeps it dark inside. The outside was stained and coated with polyurethane. (I think it looked better before it was stained.) The door in the lid has a weight in it to help it close.


 
Top View
In action. It just turned off the switch.
 
Kirk
Ready for delivery to the hospital! Everything Matt touched had to be sterile, so it was wiped down with 90% Isopropyl alcohol and sealed in a zip-lock bag. How they handled the microbe covered zip lock bag, I don't know. I had to touch it, and it was exposed to the air.
 

Gizmo
Gizmo
Here's a smaller version I made for Andrea's dad. He named it "Gizmo".

Matthew Knoebel

Matt survived his ordeal. Here he is in 2016. Because of a bone marrow transplant he is now mostly German. He will be attending Drexel University to study engineering, so there's your proof.


This concludes today's broadcast.

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