Inspire meeee!!!

[DaveW]

Ok, anyone who's been following the IPS1 worklog (http://www.thebestcasescenario.com/forum/showthread.php?t=2351) will probably have noticed that you havn't seen the front of the computer. That's because i'm not happy with it at all, and i need help to get it finished.

I know exactly what i'm doing with the front, appart from the switches. It's only going to have 4 buttons, 3 which control the drives and one to power on and power off. I don't care about the 3 drive buttons at the moment, but the power switch needs to be something special.

The themes for the case are things like:

Light Industrial
Science Fiction
Warning Signs
Matt Black & Gloss Orange
Orange Perspex
Black Mesh with led's behind it
Hazardous Substances

Do those words spring to mind an interesting type of switch? Something interesting that hasn't been done before? I was sitting staring at my sketches for about an hour today, trying to come up with ideas, but i'm dry at the moment, and i could use your help. I didn't want to post in the worklog and make a mess of it, but you should probably have a brief look at the photos to give you some idea of what the case will look like. Thanks guys, i know i'll get some helpful replies :)

-Dave

[TheAtomicMan]

How about a PVC-type valve? Or maybe some sort of touch switch (http://www.aaroncake.net/circuits/touch.htm)? Kinda hard to get a feel for the case at it's current state. Maybe a giant power lever. Like in every single scifi movie ever.

[Rankenphile]

http://www.sscnet.ucla.edu/geog/gessler/topics/switch-rotary-dpdt.jpg

[opengswede]

^^^^^
I was thinking the same thing.

Or a giant hand touch switch, which reads your palm print (or fakes it with LEDs scrolling across the hand).
like this: press with hand (the whole plate lowers slightly), scroll light across the surface, wait a min, then start the computer)

i'm sure you can visualize (is it spellt with an 's' in GB?) it, there are plenty of those in games, movies etc. It would be kind of nice to have the plate with a red matrix across, with a hand outlined in yellow to press. I'm sure this won't be too hard for an engineer such as yourself.

-.erik

[xmastree]

http://www.pentlandsecurityscotland.co.uk/images/fire_alarm_box.jpg

Replace the glass with some flexible plastic and it won't break every time...

You'll need to modify the switch, since they are usually held in by the glass, and pop out when it's broken. All you need is the front, with a momentary pushbutton behind it.

I used to work at a place which made those. I was (among other things) tech support. One school headmistress called, asking if we could supply unbreakable glass as the kids kept breaking them...

[DaveW]

Im loving the ideas guys! I had thought about those swithes Rankenphile, but i ruled them out for 2 reasons;
1) Their size
2) I want something that's going to 'spring back' to it's original position.

Of course, i can easilly modify the switch to make it spring back...but then there's still the problem of size. I have around 3cm wide and 12cm max hight for this switch...

If you look at this plan, the switch is going to go to the right of the fan hole.

http://i44.photobucket.com/albums/f39/DivW/Front_Panel.png

As you can see, it's a tiny amount of space. When i get a chance, i'll post a sketch of the front of the case, showing why i'm limited to such a tiny space.

Xmastree, i really like that idea! But i'm not certain it ges with the rest of the case-if you used to make them, would you be able to think of any other styles of those emergency buttons? Maybe ones that were orange say?

Keep throwwing ideas at me guys; sooner or later something's gonna stick. Thanks for everything so far.

Oh, and we do spell visualise with an s in GB. :) Nice to see you know your languages. Oh, i meant to say, eric's idea is great, but instead of a hand i'd limit it to a thumbprint maybe? And have it glow when the case is starting, with a thumbprint on it...Hmm...that's a pretty good idea...i'll think how i'd go about doing that and get back to you guys-till then, please keep them coming!

-Dave

[xmastree]

Xmastree, i really like that idea! But i'm not certain it goes with the rest of the case-if you used to make them, would you be able to think of any other styles of those emergency buttons? Maybe ones that were orange say?It's only paint... We specialised in fire and security systems, so all ours were red. All you need to do is think of an emergency action and develop that.

Someting like a gas release system, I think they are yellow.

http://www.advancedsmoke.co.uk/images/callpointswitch.jpg

More ideas:
http://images.google.com/images?q=emergency%20switch

[Omega]

Spring loaded military cover style switch?

Either that, or you can get a military toggle style switch, and a push-button switch, and wire them so that the push-button cannot work unless the military style is on.


So like this:
(when military switch is off):

Mobo cable thing->military style switch->ground

(when military switch is on):

Mobo cable thing->military style switch->momentary button


That would be pretty awesome.

And label the military switch "Prime" and the button "fire", and have a plastic/acrylic cover over the button, and underneath, that horozontal warning line stuff.

http://www.thinkgeek.com/images/products/zoom/spst-switch.jpg
Example of the military switch

http://www.coin.demon.co.uk/parts/pimage/v0104.jpg
Example of a pushbutton switch (for this, you can make it say "ON" or something, and make a cover for it.

Maybe i'll just draw what i'm talking about, since i can't find pics =/

[opengswede]

Oh, i meant to say, eric's idea is great, but instead of a hand i'd limit it to a thumbprint maybe? And have it glow when the case is starting, with a thumbprint on it...Hmm...that's a pretty good idea...i'll think how i'd go about doing that and get back to you guys-till then, please keep them coming!

-Dave

Yeah, when I saw the drawing (which I should have looked at in the first place, I thought thumb (or fore-finger) reader too. I actually think you could incorporate a real one into the case and have it close the mobo start ciruit when it's you pushing the button.

You can also do a magnetic key card reader, but fake it so that the magnetic slide thingy is there (not sure what it's called, the reader part), but inside there is a small switch which gets triggered by a card sliding through the reader (mecanical not magnetic). Not sure if it's a great explanation but it's early and I'm slightly time restraint.

-.erik

Btw, this is fun, comming up with ideas (i'm must better at that then completing things, as my gf said the other day: she supports my hobbies since she knows they'll never take off in any serious mannor. HAH! she just wait...).

[xmastree]

When I posted the call point idea, I hadn't seen the space available. Obviously a 4"x4" box won't fit there.

Is the PC going to be a permanent fixture? Mount a call point on the wall nearby, and plug it into a socket on the back. Be sure to use proper conduit for the wire, at least until it's out of sight. ;)
Then mount a switch on the back for those times you need to power it up elsewhere.

You could illuminate it too. Either permanently, or just when it's on. I'd go for the permanent option.
I just did a quick test on my testbed mobo. Connected a standard 3mm LED to the power switch header. Unfortunately there isn't enough current available to light it. It glows but only just, so you would need to run four wires and get the LED's power from somewhere else. I would suggest using the +5V power intended for linking to the USB ports, I'm sure that's available on the header pin, but I can't find my multimeter so I can't check.

[opengswede]

during a presentation today (not mine, i just listened, or daydreamt rather...) I thought you could use a pinball plunger. That shouldn't be too hard to mod into a power switch. The only problem would be that you might pull the computer to the floor by starting it :rolleyes:.

Or, here I go again, something like this:
the-big-red-button-of-doom (http://www.engadget.com/2005/01/18/the-big-red-button-of-doom/)
maybe just the button (i don't know).

I really should do something useful now.

-.erik

[xmastree]

Thinking about Rankenphile's Frankenstein switch gave me another idea...

What do you want the switch to do? Just turn on? If you don't need the hold down to power off function, only a momentary action you can do it easily.

Use a discreet monostable. In its simplest form all you need is a capacitor, although you will need a discharge path for it. Using a transistor would be better.

Basically, close the switch either way and it sends a pulse to the computer to turn it on. Shut down either with software or by throwing the switch the other way, sending another pulse to shut down.

It has to be wall mounted though, and you'd need a little ugly man calleg Igor to operate it during storms.
http://visioncrew.com/Images/frankenstein_2.jpg

[opengswede]

It has to be wall mounted though, and you'd need a little ugly man calleg Igor to operate it during storms.

And you need to practice your diabolical laugh.

-.erik

[xmastree]

Here's (http://www.boreme.com/boreme/funny-2002/electrical-arc-p1.php) a nice industrial switch...

[Omega]

the-big-red-button-of-doom (http://www.engadget.com/2005/01/18/the-big-red-button-of-doom/)



That kind of button! that is the kind i was talking about!

With the cover and you have to use a key to open it.

[DaveW]

Holy hell xmastree, i don't think i want one of those next to my computer. In fact, i don't want to be next to one of those full stop.

I had some ideas, and i think i might do with the thumb button, and incorporate an idea i had a while ago; i'll post up a sketch in a few days, so you can see what i'm thinking.

-Dave

[xmastree]

Humph. I dunno. :rolleyes:
We come up with all these neat ideas and you go and do the thing you first thought of. :p

[DaveW]

Oh no, i'm thinking about using the thumb for the power switch. I got so wrapped up with thinking out switches that i decided i had to use some of these ideas; i'm going to use another idea for the CD drive switches now. I'm trying to figure out how feasible the thumb switch is; it shouldn't be too difficult, but i'm trying to think about how much space i have...

Trust me, i appreciate the help guys! I only thought up the idea yesterday, so like i said i'll post something when i get the chance.

-Dave

[jdbnsn]

Ok Dave, I'll give this a try too since it is way more fun than studying for boards (I am finding myself more easily distracted than ever:redface: ). Ok, your list of theme criteria: I tried to meet them all and think I can:

Light Industrial-I thought of gears naturally
Science Fiction-hmm, not of this world, maybe alien design
Warning Signs-I'll get to that in a sec.
Matt Black & Gloss Orange-got ya covered
Orange Perspex-ditto
Black Mesh with led's behind it-I'll explain
Hazardous Substances-ditto

Here is the basic design I had in mind: (By the time I got to the gears, I screwed up so many times I had to cut out the rest and glue it to another sheet, the never did come out good, but hey, this is just a concept drawing.)

http://i51.photobucket.com/albums/f395/jdbnsn/misc/MechButton.jpg

I know it looks like a lot of work, and it would be, but Dammit Dave I know you could pull it off and it would be sweet looking on your case. You would want to work from inside to outside. Start by finding anything dome shaped whether you want opaque and coloured, or translucent and coloured with an internal LED would make a difference on what you selected. I recommend walking around the grocery store and look at cooking utensils, and products packaged in plastic bottles of various shapes. When you find your dome, cut it and decide how you want to mount it on your power button. Then the next layer can be made by cutting a piece of perspex in a ring and colouring red or somehow get it fixed up so that a red LED (spliced in with the "power on" lead for front panel LED) outlines your button. Then the same goes for the next layer, the top part of the ring is illuminated by a green light in my drawing, but I think red would be better, use this for the HDD light and the red will flicker when the HDD is accessed kinda giving that Hazard look. The bottom ring is the power on LED lit orange to match your scheme. Then everything else can be cut out of any material and carved and painted to match the case or drawing or whatever you like best. (I know you have a Dremel Dave, time to do some 21st century whittling).
Ok, that coveres every criteria except black mesh and hazardous substances. I suggest getting some fine mesh, like the king used for car speaker grills, and building a small rectangular boxed shape, then you could make another carving of perspex in the shape of a biohazard sign, and again wire some LEDs under it. Then cut a hole to mount the awesome switch you just made adjacent to it. Well, I think that covers all the criteria, good luck with the integration project, looking forward to seeing this puppy!
Jon

[xmastree]

Dave, I got an idea for ya.

That touchpad from the knackered apple laptop I have. It's 2" x 2.5". It might fit, and you could probably figure out some way of powering it from USB 5V on standby, and making it respond to being stroked in a particular way (stop sniggering at the back!). You would need some messing around with a PIC and stuff, but it would sure be unique.

http://i50.photobucket.com/albums/f341/chrispollard/mactop/padback.jpg
http://i50.photobucket.com/albums/f341/chrispollard/mactop/padwires.jpg

The larger of the two switches is no longer available, as it's now mounted in my 5.25 drive as the power switch.

It's yours if you want it.

[xmastree]

Here's another idea I had whilst looking through the bits of my 5.25 drive.
A thing like a card slot, with photosensors inside it. And a credit card with holes drilled in the edge. Push it in to activate a microswitch at the back, but it will only work if the holes are in the right places.

[guitar.child]

i wonder if you could so something liek a coke machine. just the coin slot. so when you drop a coin in the turns the machine on and when you hit the coin return it turns it off. that would be kinda cool. that would be neat for an idea a coke machine with a side panel that lit up when you turned it on and have the seletion buttons disguised as cd drives. just an idea.

[GT40_GearHead]

i wonder if you could so something liek a coke machine. just the coin slot. so when you drop a coin in the turns the machine on and when you hit the coin return it turns it off. that would be kinda cool. that would be neat for an idea a coke machine with a side panel that lit up when you turned it on and have the seletion buttons disguised as cd drives. just an idea.

you could leave the coin in there, you know.... for dark days :rolleyes: :D

[DaveW]

I knew you guys wouldn't let me down! I've been inspired. So much that i might have to make 20 cases to work all these idea in together!

Jon, i like your sketch, and it reminded me of something that i was going to do, (have a single red LED glowing when the computer is off) and i realised that i could incorporate that into that switch you drew! And then the switch would be...hmm...tel you what, i'll be back tonight with some sketches of what i have in my head now, thanks to everyone for all their great ideas!

xmastree, i'm thinking about that sensor that you were saying, but it would take a hell of a lot of PIC programming to get it to recognise a particular signal pattern. It might be possible...how many pins does the touchpad have? Looks like a whole Busload there...i really like the idea, but it might be more trouble than i can handle at the moment.

Thanks guys- I will be back!

-Dave

[DaveW]

OK, i managed to get that sketch scanned in, although my scanner's chopped a bit off. This was that idea that i was thinking about, and what i think Jon was talking about earlier.

http://www.thebestcasescenario.com/davew/scan.jpg

-Dave

[jdbnsn]

I have been looking at that sketch sitting on my desk and I think it needs improvement. I could try some modification, would you like to see more alien tech, or more industrial?

[DaveW]

I'm not sure...

why not go for what feels right? I trust your judgement on this one. I'm liking the design so far...but i suspect it might end up being made with what's lying around. I might have to watch the gear, because of the width, so have you got any suggestions for making it...taller and slimmer?

If push comes to shove, i can re-arrange the locations of the buttons.

I think i'm going to use the buttons i sketched above for the CD drives, unless something better comes up. I'm signing off for the night (it's night here) so i'll see you tommorow.

-Dave

[jdbnsn]

Sure Dave, I can make it slimmer. I think the way to go is lose the gears. They are not as appealing as I once thought, they look kind of corny. I drew up a really rough draft of a box you can mount the button on. What I would do is remove the gears and put custom cut piece of metal or plastic (thick is good), with the shape being circular but having rounded "bumps" on four edges in a square formation. Look at the picture:

http://i51.photobucket.com/albums/f395/jdbnsn/misc/Buttonstage.jpg

You go to a junk yard and find an old bike, take the brake cable and strip the plastic coating off to expose a metal snake-like cable and attach as shown above. Cut a box out of a car speaker grill and flatten it, then bend into a box. Mount a metal plate on the top with your patented angle cuts in it then paint to match your case. Mount the button off center or center (which ever looks better to you). Attach the brake cable to the four "bumps" you made on the ring around the button and fix the to the corners of the box to hide the cut edges. Lastly, (oh how cool this would be!) grab a large washer (biggest you can fit in the interior of the box. Buy one of the cheapo 1.5V motors the use for small toy cars and such and sand off the gears on the axle. Replace the gears with a strand of rubber band that you cut to size and wrapped around the now cylinrical gear post thingy. With another rubber band (cut), painstakenly glue around the edge of one side of that monster washer to make a track of sorts for the motor to grip. Mount a plastic spray bottle cap (tiny one like what comes on a sport drink at the gas station) on the other side of the washer and cut a hole out of the bottle cap on one side or both. Paint the inside of the cap ( or if you have the patience mount aluminum foil on the inside). Build some sort of platform that will hold the motor and washer together as needed to make it turn. Mount an orange LED with wires running through the front of your case (not attached to any of the above mentioned parts. This would give you a rotating hazard light and you could figure out how to make it turn when you wanted it to. What do you think? If you're not pressed for time I could build it for you but it will be a couple of weeks before I can get started.
Jon

[DaveW]

Wow, now there's an idea! I hadn't thought about putting little rotating hazard lights onto the case, That idea is amazing.

I'll go into the cellar if i get a chance and see if we have something lying around that will help to make this. We've got plenty of those little motors lying around, so i'll have a look and see what i can throw together later in the day.

Thanks for all the great ideas, this is really beginning to come together!

Maybe i can even make a sort of orange cap, if i have enough perspex left over (which i should) and i can make some interesting features for the left hand side of the case as well...I think i need to get some photos of the case, i'll make an attempt to do just that after i've done a couple of hours of studying.

It's crazy, i had a million ideas for this case, so many sketches and doodles, and then all of a sudden my inspiration just dissapeared. If you've ever been in that situation you'll know just how frustrating it is. Thanks for getting me out of my creative rut guys-and i really mean that!

Oh, and if you have any other suggestions related to the above themes, then feel free to drop them in.

-Dave

[jdbnsn]

Glad you liked it, let me know if you need help throwing it together.

[Nagoshi]

After reading the whole 3 pages of this thread while downloading something (couldnt see one image, except for the sketch that I could not understand very well ^^;) I thought of somehting, about the fingerprint reader...

You could find a way to print a fingerprint on some kind of tansparent layer, and by sticking the stuff with leds of the color of your choice, black colored layers and other stuff, you could make some kind of fingerprint display that would light up when you press it. If you got the time to play with a little mechanism, you could make the led(s) move up and down while you press it. The ''switch'' would be activated when you press the ''reader'' by a spring and some kind of button (i suddenly thought about xmastree's 386 case and its new power button, you could get something similar done, but instead of the original 5.25 stick it would be your reader).

I know that some motherboard will leave the power LED lit when they are shut down, not at full power tho, but you could lit your reader with the power led when its shut, and gives some light when it's powered, and by using another led connected somewhere else, to give the light fx wanted.)

Simple suggestion tho, but I really liked the fingerprint reader. Hope I have helped for yoru choice. :)

[jdbnsn]

Hey Dave,

I forgot you wanted to operate multiple buttons so I updated the design a little (remember these just suggestions). I drew a new diagram to illustrate what I am jabbering about:D :

http://i51.photobucket.com/albums/f395/jdbnsn/misc/buttonattachment.jpg

The colors didn't come out real good, but the top figure is orange (as well as the color or the stripes on the warning sign) and the light caps and warning letters are red. I am not quite sure where you could get those caps but I assume if you looked at various products that come in tubes (glue, etc...). The top figure is an idea of hiding the optical drive switches and whatever else you are using. I was thinking that you could place the optical drive LEDs in the red caps and a clear LED under the warning sign. So when you access a drive, that red cap blinks. You could print that warning sign on transparency and fix it to perspex. As for those rocker arms that attach to the pistons for your switches, you would need to make their attachment points (inside the box) movable so they can slide back when you push down or they will put force down and laterally which will bind up the piston. Anyways, just thought I would throw this in as an option for ya to think about, now run off Dave and be "Inspired":p
Jon

[jdbnsn]

I forgot to mention, realizing that you need a slim design, those rocker arms could be installed on the shorter edge rather than the way I drew it. And the other two items (light panel and warning sign) could be mounted anywhere. Actually, so could the rocker arms for that matter.
Jon

[Ohtarnehtar]

ok, it would take a lot of fabrication, but in the end would have a good effect. Take the center of jbdnsn's design (the button in between the 4 tubes). If you do something similar to the rotating lights before, you could have the red and green LEDs rotate around the button when you push the top rocker arm (or bottom, whichever) You would need to put a similar motor device on, and you could have a little tab on the rotating LED assembly so the button can only be pressed when it is fully rotated. I'll attach sketches later...

[DaveW]

If anyone was ever in doubt that you had exams bud, this thread is all it would take to convince them otherwise! It's amazing what your brain will find to do in order to avoid having to study, eh?

I'm currently taking appart an old CD drive for the drive opening motor, i figure that's at hand. I don't want it to make too much noise...and although i like your idea, i've come up with something as well, but i was scanning it in when i realised that it's going to be next to an Amber LED cooling fan with a fan grill with the cross hatch pattern...and i've allready over used that!

http://www.thebestcasescenario.com/davew/Scan0001.jpg

So my idea sucks, but i'm posting it to let you know how i'm thinking.

I'm also liking your military style light bulb protectors-wonder if i can make some of those...and where would i put them? I think i need to take time out and draw a full sketch of the computer's front and sides in order to give you guys a decent idea of what it's going to look like.

Be back soon!

-Dave

[jdbnsn]

You said it man, nothing beats not studying!

For those bulb covers I had a thought. I don't know if you have them in the UK or not, but I have seen candy sold in tubes which are shaped exactly like test tubes but small (maybe .3 inches). I would place them in the proximity of the power switch, wherever there is room (and they can be made quite small), but if you place them too far away they may not appear closely related to the scheme of the power box. For the front of the box you have drawn, are you going to put a rotating light inside? If so, I would finish the light mechanism first and then see if it looks better with an opaque facade with the beam shining only out the sides, or something you can see through. It will probably come down to how pretty you can make that contraption look. If you could find those you could cut the ends off and paint the brackets on. Oh and by the way, I don't think the mesh is overused, but then again, I just love the way it looks.

[Ohtarnehtar]

ok, heres my idea... you would have to add some sort of assembly so that you couldnt press the button until green is on the botton, and you would have to wire it so it would wait there for a couple seconds, then continue rotating until green is on top...lot of fabrication involved
http://i72.photobucket.com/albums/i178/Ohtarnehtar/LEDrotatingasmcopy.gif

[DaveW]

Actually, we wouldn't need to make that turn-an 8 pin PIC microprocessor hooked up to 10 2 way LED's could handle that without any moving parts...actually better make that a 16 pin if we're using two way LEDs.

Which would let me have it completely red when the computer's off, an eirie red eye in the darkness... ;)

the first person to make a HAL/Dave reference is getting the most obvious joke ever award.

ANYWAY! Here's a poor sketch of my ideas at the minute.

http://www.thebestcasescenario.com/davew/Scan0003.jpg

I'm planning to use that metal body filler to make sort of...ribs? I'm having trouble describing it, just think like a line in the metal that comes up, quite smoothly, to stop it from being completely flat. I'm also keeping my eyes open for Diamond Plate-i'm not sure if it's something my old supplier would be able to get me, but this is Glasgow, so i'm sure i can find some somewhere. I'll raid the scrap metal merchants if it really comes to it. All the diamond plate is for is to 'feature' the metal. I'll cut of symetrical shapes and attach them in places with too much bare metal.

Although i was planning to paint the aluminum orange, i think i'll polish it now. Blame tribaloverkill for that.

I was planning to cut up bits of metal box and pipe and basically make a sort of industrial 'texture' to the left hand panel. I started drawing a sketch but left it because i just knew that it really all comes down to what's lying around.

Now Jon's put the idea into my head, i'll be sticking a rotating hazard light on the side, that will flash when there's button activity, unless i use that idea on the front panel. Then i'll either make it a flourescant tube or maybe some of those lights...which if i don't stick on the side, i may just stick somewhere else...although i feel unceratin about painting a plastic, i don't think it would look good. Ironically i have a large amount of modelling wire sitting around here somewhere, which i can use to make cages and such.

Any more ideas, feel free to drop by! Thanks again guys :)

-Dave

[jdbnsn]

That looks great! I think I see an opportunity there for the design I used earlier if you were thinking of going that way. That box on the front with the 120mm fan, I assume that is a HDD cooler? If so, you could either move the fan to the other side with a shroud to pull air across the drives into the case, or just keep the fan blowing out of the case and mount it deep enough to use the box you have drawn there to mount the button and cables and such. You should be able to fit the motor and rotating harard light inside that. And if you use mesh on all sides you should have plenty of airflow.

[DaveW]

Actually, the front panel's nearly 4cm thick, so there's lenty of space inside for all the electronics, fans, etc. and anything else that i come up with. I'm still not sure how i'm going to attach this, i was thinking of putting hinges to the right hand side, but i think just now i might end up bolting it on?

The 120mm fan is more of a feature than an effective cooler; i allready have an Akasa twin fan HDD cooler to install on the inside. It's just to keep an airflow going at the minute. I think that this is becoming sort of 60's military in it's own way, so i guess we can add that to our keyword list.

Anyway, i probably won't be able to sleep tonight now. Too many ideas thumping around; before i was stuck, now it's trying to get everything on, and trying to think about what to drop, how to get it on...aye caramba, eh?

-Dave

[jdbnsn]

Ha Ha Ha! I know the feeling, but at least you're not studying, right?
Jon

[xmastree]

xmastree, i'm thinking about that sensor that you were saying, but it would take a hell of a lot of PIC programming to get it to recognise a particular signal pattern. It might be possible...how many pins does the touchpad have? Looks like a whole Busload there...i really like the idea, but it might be more trouble than i can handle at the moment.Asuming you mean the conenctor, it's a 20 pin connector, but some are common. 1,11,13,14 and 20 appear to be ground. See it on the right side of the photo (http://i50.photobucket.com/albums/f341/chrispollard/mactop/padback.jpg).
Along the bottom and the left side )partially covered by the barcode label) are evenly spaced via holes, which presumably connect to the pad itself.
No point picturing the other side, it's just plain black.

PM me your address and it's yours. Even if you don't use it in this project, I can tell you would love to mess with it...

[DaveW]

I've sent xmastree my address, because you can never have too much apparently useless junk electronics. ;)

-Dave

[xmastree]

I've sent xmastree my address, because you can never have too much apparently useless junk electronics. ;)And I'll send it because I hate throwing away perfectly good stuff, and I have neither the skill, the equipment or the time to figure out how it works.

Here's a start:
http://www.snark.de/mac/tpad/

[DaveW]

Ohh good link! (saves)

-Dave

[Cool1Net6]

Sorry to clutter, as it seems your not using this idea, but I just want to "engineer" Nagoshi's idea a little furthur...

You could find a way to print a fingerprint on some kind of tansparent layer, and by sticking the stuff with leds of the color of your choice, black colored layers and other stuff, you could make some kind of fingerprint display that would light up when you press it. If you got the time to play with a little mechanism, you could make the led(s) move up and down while you press it. The ''switch'' would be activated when you press the ''reader'' by a spring and some kind of button (i suddenly thought about xmastree's 386 case and its new power button, you could get something similar done, but instead of the original 5.25 stick it would be your reader).
This can be done with several narrow beam LED's, a piece of perspex, an interesting background image, and a touch sensor. You place the touch sensor behind the "fingerprint scanner" and when you touch the scanner itself, using a microcontroller you can program it to "scroll" the LED's up and down as if its reading the finger. The trick is to get the LED's to show in rows and have each LED 'row' flicker on and off for a brief time. This simulates a scanning action and avoids moving parts.

But I like the rotating actuator switch with the spinning biohazard type thingie that I dont completely understand idea.

-Cool-