Techno-geek Roulette (or Who Makes the Coffee?)

This is a gadget made from recycled computer parts to give an absolute, unequivocal and irrefutable answer to that eternal office question - "Whose turn is it to make the coffee?" Each time the power is turned on, this wonderful device will randomly select a person to do the coffee-run.

Step 1 Bits and PCs

You will need the power supply unit (PSU), CDROM drive and a blanking plate from an old computer - The older the better. Also, a blank writable CDROM, a selection of small tools, a glue gun and a way of decorating the CD. If you're after accuracy, a protractor too.

The blanking plate is the 'L' shaped bit of metal you take out when you put a plug-in card in the PC. If you're like me, you've probably got dozens lying around until you actually come to need one - then you can't find a single one.

The CD drive must be a read-only type. Some drives work better than others for this. If you have a couple of old drives available, power them up in turn with a blank writeable CD in and see which one spins for longest before stopping. This will be the best drive.

The best type of blank CD to use is the type with a matte white topside which you can print onto with an inkjet printer. If you don't have printing capability, you could use permanent ink marker pens or enamel paint.

Comments

[blackbeardlion]

so under engineered yet so awesome!

[Kornelie]

 haha, sweet :)

[hapman9]

Hey i have tried this but it didn`t last long as the cd drive fried if you know a sollution to this please email me back at [e-mail] Thanks that would be great

[AndyGadget]

Must have been a dodgy drive you were using which would have failed anyway. This isn't making it do anything it's not designed to do. It's just using the normal cycle it would go through if an unreadable disk is put in it. Try a different drive.

[hapman9]

thx for that i am going to get a new old tower from a store i know

[dark sponge]

"...to produce a beverage which is almost, but not quite, entirely unlike coffee"

-The Hitchhiker's Guide to the Galaxy

I absolutely love that book!

[dontno]

Don't forget your towel!

[Derin]

The towel in towel.blinkenlights.nl?

[rct1113]

I thought it was tea....

[AndyGadget]

Yep, it was tea; I paraphrased the great Mr Adams. And machine tea is always at least infinitely worse than machine coffee. To keep that brain cell working it has to be the 'real thing'. (And I dont mean Coke - although that statement could open up a whole new box of frogs ;¬)

[dark sponge]

Oops, I forgot. I read the book awhile ago, and can't remember some of the details. Yes, it was tea.

"...to produce a beverage which is almost, but not quite, entirely unlike tea"

[shammallamaman]

Amen Brother

[twenglish1]

not sure if it has been said but you should mark a pointer on the cd tray inside the computer put the disk in and after a couple seconds open the drive and look where it is

[skappa]

Could you also..build the "Roulette" Inside your machine? By attaching the wires of the PSU to the cd-rom drive i think it's possible. Everytime it tries to read the disk, it starts spinning :)

[Caspar]

Suggestion - Get some little magnets and glue them on the dividing lines on the wheel (North pole facing outward). Now glue another on the pointer so that as the wheel spins this magnet (North facing in) repels the ones on the wheel. If the wheel stops near a line, the repulsion of the magnets will move it one way or another, guaranteeing no arguments. To be really sure you could put another magnet (South facing in) a bit away from the pointer so the wheel would stop in the middle of a segment. Magnets would have to be weak enough or far enough away so they did not prevent the wheel from starting when the power was turned on. To overcome the unevenness when slowing down (which you mentioned), you could increase the inertia by making the wheel heavier, and also allow some slippage between the shaft and wheel, or, after finding more preferred stopping places (eg 12) than people, divide the wheel into 12 segments, and mark some of them "spin again"...

[AndyGadget]

Thanks for the magnet idea, but I think I'll stick to 'rock scissors paper ;¬) It's only some motors which have the preferred stopping points - most don't. The one I used in the project has 24, so the six segments have 4 each. I aligned the disk so it couldn't stop on a divider. Actually, if the number of stopping points is not exactly divisible by the number of segments, it would be a way of biasing the result {evil grin}. If you use the more common motor type with no preferred points, this won't be an issue. The 'spin again' idea is a good one if you want a fair wheel and have the wrong number of people (and only that type of drive).

[garrettmikesmith]

my shop teacher used one of these to decide what would happen to you if you came to his class tardy.

[YAY RANDOM !]

I remember doing this with a hard drive.

[swag]

If this is a "pointless" contest, I'll vote.

[earnst2w8]

if you use magnets or sticky tape you could add different cdroms , for different tasks( so you dont have to build 20 or so machines for 20 tasks, then you just make 1 machine and 20 cdroms) just an idea :D

[jongscx]

or not even really... the spindle WAS originally designed to keep a spinning CD secure on it...

[AndyGadget]

The spindle alone will not hold the CD. On the wrap-around lid (which is thrown away) there is the other half of a clamping mechanism for the disk. Because this is gone, the CD has to be glued on. If you use magnets or tape to stick another disk to the fixed one it will have to be very well balanced or the whole thing is going to leap all over the place. Those things spin pretttty fast!

[earnst2w8]

thats right but if you just used a round magnet with a hole in het middle i think balancing wont be such a problem

[jongscx]

Oh yeah, ring magnets... just do two, one inside, one outside... do they make those in a decently strong variety? all I've seen are the black ferrous type, not very attractive at all...

[earnst2w8]

http://www.magnetsource.com/Consumer%20Pages/BasesLatchesAU.html
magnets like this but then with a bigger hole

[earnst2w8]

i dunno you can get a round magnet and drill a hole ( i dont know if it will word , never done it :D) but jou just have to search for it on tha WEBB by the way do you live in the united states and is it there now 16:23 or 4:23 i think 16.26

[earnst2w8]

sorry the times arent right 'am' is mid day and 'pm' is night and in the mornig right?

[jongscx]

If you flip the CD backwards so that the shiny side is out, and shine a laser on it it makes a cool design on your wall...

[alex-sharetskiy]

This is worse then russian roulette! only kidding Great instructable! i would have never thought of that

[KE5GQI]

Nice Instructable Phase 2 is to build in a bias so you never have to...

[T-K]

Very original! Nice use of an old CD drive!

[Weissensteinburg]

Cool! Just don't bring it to the airport...stasterisk can tell you that much.

[V-Man737]

You could put it in a cardboard box so that the wires don't scare the TSA. Then you'll be safe. ;-)

[KaptinScarlet]

that is so cool. You could make up loads of different CDs for different questions, roulette wheels, should I do it - YES / NO, she loves me - she loves me not (could be designed like a daisy with some petals missing.... etc etc and the like. SuperGlue on the first disc and then use a tiny bit of velcro evenly spaced to have interchangeable discs. cool

[stranoster]

Oooohhh. Spinney. Round and round and round. "What is your bidding my master?". Anyway looking away from the mess of punctuation behind this, this is a well made Instructable. It looks great, It's well documented and the pictures weren't taken on a cellphone. It is also very original. Good work, five stars.

[Dr. Cool]

All that trouble to decide who makes the coffee? ; ) Nice Instructable Doc Cool