What do you make for a man that has most everything; a tiny waving flag, sprouts to keep him healthy and an automatic pill dispenser just in case the sprouts fail? It wasn't immediately clear. So, I looked at his profile to see what he likes. From what I could tell he liked useless machines, gear clocks and stuff. I thought for a long time about what he might want made for him based on what I already knew.
I was ruminating over one project in particular that he had built called the IRritator when it suddenly struck me, I bet he might have something that requires a remote control, like a TV (at least, I am hoping that he has a TV). Anyhow, assuming that he has a TV, I bet he has pressed the channel-up button thousands, if not tens-of-thousands, of times. That's a lot of effort being exerted to change the channel. But what if that effort was not necessary? What if there was a way to change the channel without ever exerting the effort it took to press the button? What if there was a machine that pressed the button for you once per minute? Well then, perhaps, just maybe, that would be The Most Useful Machine... EVER!
And thus, I have made janw The Most Useful Machine... EVER! for the Instructables Gift Exchange. If it turns out that he doesn't have a TV and this machine isn't as useful as I hoped it would be, then perhaps he can combine it with his IRritator and make the most annoying clock ever made. Towards this end, I have also mailed him the minute hand, so that should he need to, he can use it to trigger the IRritator for one minute every hour.
Step 1: Go Get Stuff
You will need:
(x1) over-sized universal remote control
(x1) servo motor with the controller board removed **
(x1) curved doorstop
(x1) 14" x 14" x 1/4" acrylic sheet
(x1) clock movement (with second hand)
(x1) small magnet
(x1) reed switch
(x1) extension spring
(x1) double-threaded standoff and corresponding screws
(x1) 2 x AA battery holder
(x3) AA batteries
(x8) 1/2" bolts with nuts
(x1) a few short zip ties
(x2) self-adhesive Velcro strips (the length of the remote)
** Learn how to remove a servo controller on this page.
Step 2: Cut the Acrylic
Download the files included below and use it to laser cut your acrylic to make the mounting bracket.
If, like me, you don't have access to an awesome Epilog laser cutter, you can have ponoko.com or any similar service cut the file for you.
Likewise, you can print it with a standard printer and use it as a template while working with more traditional cutting tools.
Step 3: Bend the Acrylic
Find a metal bar and a surface that can be heated and clamp the acrylic between the two, such that only the part you want to bend sticks out over the edge of the surface.
Put on heat resistant work gloves and get your heat gun.
When you are sure that it is clamped just right, apply heat using a heat gun over the length of the acrylic where you would like to make the bend. Travel back and forth over this area slowly. If you let the heat gun stay still in one spot, bubbles may start to form in the acrylic.
When the acrylic starts to soften (it will visibly droop a tiny bit), gently apply even pressure in the direction that you want to bend it and hold it in place at 90 degrees until it starts to harden and cool. When doing this, be careful to bend it the right way or you will end up with a backwards bracket.
Step 4: Velcro the Remote
Apply two strips of self-adhesive Velcro along the length of the back of the remote. Align the opposite strips of the velcro pairs along the length of the acrylic base.
I found the easiest way to do this is to attach everything, first, to the remote control and then carefully sticking the entire unit down to the base. In this way, it ensures an even alignment.
Step 5: Prepare the Spring
Use a screw to attach your extension spring to one end of your standoff.
Step 6: Attach the Arm
Fasten your doorstop to your servo horn (the gear-looking part) with zip ties. This may require drilling larger holes into the servo horn.
When you are done, trim off any unneeded parts of the servo horn and zip ties with diagonal cutters.
Step 7: Fasten the Parts
First, bolt the motor to the acrylic bracket using screws. The motor obviously goes into the rectangular hole the size of its body.
Next, fasten the reed switch to the two mounting holes near the top right. This should be mounted on the same side as the remote control.
Pass the clock shaft through the large round hole on the bottom right (towards the remote) and fasten it in place using its mounting nut.
Also, fasten the AA battery holder using screws by passing them from the back, towards the front, and then using bolts to lock it in place.
Step 8: Wiring
Pass the black wire from the battery holder through one of the holes in the acrylic above the reed switch. Fasten this wire to one of side terminals.
Twist together the red wire from the battery terminal with the black wire from the servo motor. Solder this connection together. You may want to insulate this connection with electrical tape or heat shrink tubing (if you use heat shrink, don't forget to slip it onto the wire before you twist the wires together).
Pass the red wire from the servo motor through the other hole in the acrylic and connect it to the other far terminal of the reed switch.
Clean up the wires with zip ties.
Step 9: Prep the Timer
Stick a small magnet to the second hand of the clock mechanism.
If the second hand can't spin freely on account of the remote control, trim it shorter until it can.
Step 10: Power
Power up the device by inserting batteries into the appropriate battery holders and then you are good to go.