DescentBB

Recently, I got into an endeavor that will require me to get into chemistry again. The current project requires several pieces of equipment, one of which is a stirrer.

I looked on the web and found that even a low end stirrer runs upwards of $200 and that has very low precision and almost every stirrer I saw on the web used a PC type fan with magnets mounted to it and a speed regulator.

So, I decided to roll my own stirrer, only using solid state components and a PIC micro CPU at the core to regulate speed and generate the necessary quadrature sin wave drive.

Here's a couple snaps (pre-paint job)

With a flask (around half speed)


Just the stirrer


I estimate this unit would have costed around $100 to build if I only bought the components needed. Not bad I think

hey, cool stuff dude.

Thanks Ferno!!

A buddy of mine is making a tornado tube using a PC type fan and magnets. I'll try to get some pictures of that up too.

Very nice ! Now add some USB to remote control it from the PC

Awesome job sheep: it's []D [] []\\/[] []D [] []\\[] ' Chemistry gear! See through solid state! Geek Hardware! Wicked. But where is are the bloo LEDs?????

So tell me, what's IN the flask that reacts with the magnets, to do the actual stirring?

Thanks Grendel! I don't need USB just yet, but I spose if I do, I can always convert the joystick code

Thanks Mobius! Actually, I wanted to make an LED array (8 total) that were composed of red/green LED's that would rotate with the field and illuminate a translucent ring of plastic. Supa cool!! Gotta wait until I create the design for the top first though.

The thing actually doing the stirring is called a stir-bar and is nothing more than a teflon coated magnet.

So uh, what ya cookin there sheepy?

TERRORISM!

Seriously though, good job Sheep.

Heh, I remember seeing these things at my dad's company years ago during an open house. I can't say that they looked as badass as this one, though. Nice job

Thanks for all the great comments guys!

Vulcan...I can't say currently what it's for but, it's not terrorism, heh, quite the opposite. If what I'm getting into works, it will eliminate the dependence on animals in a particular industry. Something that I strongly believe is the right thing to do. I'll be able to say if and when it succeeds.

TG...Thanks, hopefully after I paint it it'll look even cooler.

You're going to make artificial sheep cheese???? o_O

lol...no, but that sounds interesting

I don't want NUTHIN to do with no Sheep cheese... artificial or otherwise.

Blooo LED's are passe'

you gotta get emerald green LED's now.

Or get some multi-color LEDs and have them alternate like a marquee.

Nice job. Maybe a school in your area is interested in buying one? It would make sense because like you said it would've cost you about $100 to go out and but the stuff and since many schools are cutting things...

Great job! Invention is born out on nessity!

That's fantastic. Maybe you could make more and sell them for money.

Thanks Jake and Zangareth.

I don't think I'll be wanting to build another one anytime soon. Building it wasn't a whole lot of fun. I started with a steel base which I had to cut and drill to size, then the aluminum sides which are also machined, then epoxied. The coils are hand wound and each consists of 1000 turns of 28 gauge (thin) enameled magnet wire.
The program code actually took a bit longer than I expected and is about 400 lines long.
Lastly, the circuit board is so stuffed full of parts that I don't believe it could hold anymore in some areas. That's probably the one thing I'll be redoing only this time, I'll use a custom fabricated board, which I'll also make myself.

The shame is, the parts only come to $100, but if I were to charge my labor rate, it would come to well over $1000.

Still working on the template for the top. I think I'll paint the whole thing black. I was going to go with the more typical, white, but I think this just has to be black.

I think I'm going to create an animation sequence in PSP to see how the LED's will look first before making that commitment, but I am leaning towards red/green LED's at the moment.

Thanks for all the great replies so far.

Here's an idea of what the LED's would look like...



Whatcha guys think?

I think I'm gonnabe sick... @_@

Incredibly cool device!

wow man.. these drugs kick ass.. i'm actually seeing the colors turning.




sorry I just had to say it.

Sprayed the base today...Semi-gloss black. I'll get pictures up soon.

Next...the template for the top cover.

SuperSheep wrote:Here's an idea of what the LED's would look like...



Whatcha guys think?

Yes master...

Blue/white or red/white would be easier on the eyes. Mine, anyway.

or green/white.

I like it the way it is.

Got the LED's mounted and working



Doesn't look quite as cool as the animation, but that would require many more LED's and a custom driver. Bleh to that!!!

Comments?

thats lookin good man, take a video or at least post a pic of the final version

most interesting tech forum post yet

Nice work... you can get the LED effect you wanted with tristate leds. I have a hardwired version of a circuit using discrete logic that powers 16 tristate leds in a chase circuit I was building for a club years ago. It is a mesmerizing effect.

First a positive pulse is sent lighting the red segment. Next a pulse is sent on the green segment, and then pulses are sent to both segments, causing a yellow/orange colour depending on the frequency of the pulses.

Just use the clock pulse as the input and you would be done. Problem is the circuit is on a breadboard in a storage unit... a very packed one. I cant remember the chip numbers but it did involve octal tri-state logic. Perhaps I'll dig that circuit out and make a schematic so you can see how the logic generates the signals.

I'm sure however the PIC can handle the code to produce the desired effect much easier than a hardwired version.

Well, I finally got the top template done. Wanted to use a transparency, kinko's said the only machines that they had that could do transparencies was their copiers and that wasn't good enough image quality so I wound up using a paper print sandwiched between two sheets of plastic.

Still have to buff the edges and some minor other things but this project is for the most part a wrap.

Thanks for your many kind and positive comments.

How often will you be useing this in the dark?

I estimate around 0.01% of the time, but hey, it'll look cool eh?

Actually, the LED's help illuminate in low light situations and my eyes need all the help they can get

VonVulcan wrote:I don't want NUTHIN to do with no Sheep cheese... artificial or otherwise.

Heh, don't knock it until you try it buddy! Sheep's fetta can be outstanding. There's a local producer here in Christchurch, and he ages his sheep cheeses for 6 months - wow are they awesome!

I was refering to the type of cheese that might be produced by a certain sheep we all know...