Put down that tortilla! Prototype your next circuit on a soda bottle!

I look around for my ashtray, and it is nowhere in sight. Unperturbed, I grab the empty soda bottle on my desk and cut the bottom off with my soldering iron. I add a notch to hold a cigarette, and then I notice with dismay that a small blob of solder has been left behind. I wouldn't want lead and rosin to taint my cigarette butt; that could cause cancer! No, worries, I think. I'll just scrape it off. But the darn blob is clinging for dear life! Hmmm, that's interesting...

Step 1 Laying out the traces

So I set about making a simple test circuit on the remainders of the soda bottle. Why, you ask? Well, that question crossed my mind more than once during this endeavor, but I didn't let that stop me. As my mother used to say, there are thinkers, and there are non-thinkers. Or something like that. :)

So here is the second attempt. The first one worked, which you can just see on the right edge of the bottle, but it was even uglier than this one, so I decided to make a nicer one and take a couple of pics during the process.

I melted a couple of holes for the header, then soldered it in. Next I dotted holes to accept an smt LED and resistor. After dotting these holes, I went back with the soldering iron to add a good blob of solder by hanging a bead over them. Then I soldered some wrapping wire between these "tinned pads."

Comments

[jeff-o]

This is a great idea for small stuff, but watch out for static electricity! The type of plastic used to make pop bottles will generate thousands of volts of electricity which will fry sensitive components.

[klee27x]

Yeah, that's a good thought. I supposed a grounding strap could be added, in case you wanted to cover your pop bottle with laser diodes and MOSFETs. :)

[jeff-o]

Unfortunately that's not enough. The plastic will collect static charge, but won't dissipate it evenly, even with a ground strap. For work with MOSFETS and laser diodes, a nice piece of cardboard might be better. It doesn't generate much charge. ;)

[mefromliny]

Nice job. I went a bit further and used the bottle cap to hold a coin battery and led, and cut the plastic bottle to make a few simple over head lights. Me

[klee27x]

Overhead lights powered by a coin cell? That doesn't sound very practical. I'm glad to see that didn't stop you. :)

[LinuxH4x0r]

Nice. I personally prefer doing it on formica.

[dbarak]

I like doing it on a bearskin rug. Okay, just kidding. Bearskin rugs aren't cool.

[balloondoggle]

a bare skin rug might be okay though.

[John Smith]

hahaha

[LinuxH4x0r]

I like it on a water bed! lol!

[klee27x]

I'm partial to plexiglass, for all my low temp homebrew circuitry. I use a combination of freewiring, soldering, wrapping, and hotmelt gluing to get a circuit onto one side of a piece of acrylic sheet. I tack down all fragile wiring with hotmelt, oftentimes with wires routed underneath an IC. It's thicker than formica (for the same strength), but so long as you keep it all on a single side, there's no need for standoffs or a case, so the result is actually very small. Route and sand the edges, and you can permanently bond your block circuit to other like-circuits with acetone, or you can temporarily slap pieces together with hotmelt. And it's priceless to be able to see all your wiring from the bottom of the clear acrylic in case you ever forget what you did. I've even been able to pry damaged components and small IC's from these circuits for replacement, and the hotmelt underneath keeps all the wires in place.

[zachninme]

But... then you get melted plastic on your tip and then it burns and smells bad D:

[klee27x]

Actually, this was not a problem, at all. I was quite surprised at the high melting point and stability of this plastic. I had to turn up the heat on my iron to 330C to smoothly cut the bottle in half, and this plastic does not burn at this temperature... at least not during short exposure times. At no time did any plastic stick to the tip, and I didn't need to clean my iron, afterwards.

[dan]

soda bottles are made from PET (polyester), the melting point is about 230C, higher than most plastics but it is meltable with an iron.

[klee27x]

Ahhh, that makes sense. The melting point of leaded solder is approximately 230C, too. So they both congeal together. A lower melting point plastic would shrink away from the solder bead before solidifying.

[zachninme]

Hmm... I'll have to take your word for it, then. (And use a crappy tip!)

[CameronSS]

I wouldn't want lead and rosin to taint my cigarette butt; that could cause cancer!

Was that supposed to be ironic?

[JakeTobak]

I'm 99% sure that it was meant to be ironic.

[incorrigible packrat]

What about getting cigarette butts on your 'taint? That's gotta hurt...

[fynflood]

rofl. Well done sir, well done.

[GorillazMiko]

Very smart idea, looks very small and easy to bring around.

[}{itch]

.......i love it :D