My Stirplate... Cheap and Easy Build...

[smokinghole]

You might need more than 5v. I started with a 6v power supply and couldn't get much with my 2" bar magnet. So I ran to the store down the street that has a basket of used supplies for $5-$10 and got a 12v 1amp model and just put a resistor in line from the power supply to the potentiometer.

 

[bctdi]

I used the instructions from this thread to make my stirplate....worked out great.I took an old computer ...robbed the power supply from it, the power switch and the hard drive.Used the power supply and fan for the project box (just had to remove all the un-necessary guts and cut out an opening in the top for the fan.Robbed the magnet from the hard drive....Heck the only things I had to buy were the potentiometer, the knob , and the stirbar for a grand total of 14 bucks.I used an old 12v powers supply from a rechargeable flashlight.Once I got the magnets situated right it worked at full speed with a 1 gallon growler that has a concave bottom.:rockin:Thanks to the op and all the fine folks who contributed to this

 

[RegionalChaos]

Just test fired mine this morning! Woo Hoo! :rockin:

 

[platypotamus]

Hey all. I just completed my stirplate build, and I thought I would stop by to share. here's a brief video of it in action (test run, with water):

[ame="http://vimeo.com/10250447"]Homebrew DIY Stirplate on Vimeo[/ame]

I'm hoping to get it fired up with an actual starter this weekend.

Many thanks to Anthony_Lopez for the detailed instructions! rock on.

 

[lowlife]

Im trying to build a plate to use a 2 inch stir bar for a 4 liter flask. Do any of you guys think one of these would work well
http://www.kjmagnetics.com/proddetail.asp?prod=BY042
or
http://www.kjmagnetics.com/proddetail.asp?prod=BY084

 

[passedpawn]

Im trying to build a plate to use a 2 inch stir bar for a 4 liter flask. Do any of you guys think one of these would work well
http://www.kjmagnetics.com/proddetail.asp?prod=BY042
or
http://www.kjmagnetics.com/proddetail.asp?prod=BY084

Can't answer that exact Q, but I use a 2" stir bar in a 4L flask. I have two stacks of magnets spaced about 2" apart. One stack is flipped to get opposite polarity. The magnets are the little round rare earth ones that are 1/2" diameter by 1/16" thick. I hold everthing together with hotglue. I posted some pics here.

Your big magnet might work fine, too.

 

[smokinghole]

http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=67488

You can order those online or if you have a store nearby. I used them with a 2" stirbar and I stacked I think 3 or 4 on the fan with a spacer. It works very well and they were cheap. I have two left over holding things on the fridge.

 

[darkfrog13]

I just made my own version of this. Seems to work great on my test sample. I put up my how-to with pictures and video up on my blog:
http://stubborndog.wordpress.com/2010/05/09/diy-magnetic-stir-plate/

 

[Anthony_Lopez]

Just renewed my subscription, glad to see this is still going. Keep up the good work guys!

 

[camiller]

I just made my own version of this. Seems to work great on my test sample. I put up my how-to with pictures and video up on my blog:
http://stubborndog.wordpress.com/2010/05/09/diy-magnetic-stir-plate/

Not bad. I'd be a bit concerned about the suitability of the materials for your homemade stir bar. I'm not sure that the wire insulation or hot glue are food safe. If you were just doing it to test with water that's fine but I would either think about getting a real stir bar or finding a better suited coating (food safe) for the homemade one.

 

[fusa]

Just got my stir bar in the mail from Scientific Equipment of Houston. Tested the stir plate, after a couple of tries to get the bar from throwing, it worked great.

I had an aquarium fan I use to use to cool my stereo cabinet, but after changing to an open air cabinet, I no longer used it. A coworker dropped his external hard drive, and gave me the broken case (the circuit board was messed up, the plastic case was fine) I moved the rubber pads from the side to the new bottom of the case, and added felt pads to the top and sides of the fan, as well as washer, and magnet from an old broken hard drive.

It stayed very stable, although a little noisy from the stir bar spinning. After letting it run for an hour, it didn't throw the bar.

 

[sprocketmaker]

I read this thread, and decided I can build a stirplate! Easy right. HA!
I already have an old hard drive for the magnets, and several 12 volt wall chargers, all i need is a fan. So I asked my IT guy at work for a 12 volt fan, and he gladly obliged. Got it home and went to wire it up, and I got 4 black wires (see pic). Now I'm not a retard, nor am super proficient with electrical, but every fan pic I see online, has red and black wires... Most of the pics on this thread have red and black wires... so why would I get the one with 4 black wires. I'm assuming I have a positive, a ground a control and something else... anyone have any clue which is which, or should I just scrap it and get another fan.

I striped back the wires on an old cell phone charger, and did the test meter touch and go on every terminal on the 4 pin connector, and nothing.

 

[NoNothing]

With 4 wires the hot and neg will be paired. They should be on the outside as in +-xx or xx+-. At least, being in IT myself that has been my experience.

 

[smokinghole]

I read this thread, and decided I can build a stirplate! Easy right. HA!
I already have an old hard drive for the magnets, and several 12 volt wall chargers, all i need is a fan. So I asked my IT guy at work for a 12 volt fan, and he gladly obliged. Got it home and went to wire it up, and I got 4 black wires (see pic). Now I'm not a retard, nor am super proficient with electrical, but every fan pic I see online, has red and black wires... Most of the pics on this thread have red and black wires... so why would I get the one with 4 black wires. I'm assuming I have a positive, a ground a control and something else... anyone have any clue which is which, or should I just scrap it and get another fan.

I striped back the wires on an old cell phone charger, and did the test meter touch and go on every terminal on the 4 pin connector, and nothing.

Cut the plug off and try adding power to the wires. If single wires don't work pair them up like mentioned and you might end up digging where there's taters.

 

[sprocketmaker]

With 4 wires the hot and neg will be paired. They should be on the outside as in +-xx or xx+-. At least, being in IT myself that has been my experience.

Thanks for the responses... I just found this Pin Out Diagram, which seems to confirm your advise, so I'll give it another try tonight.

Cheers!

 

[NoNothing]

Thanks for the responses... I just found this Pin Out Diagram, which seems to confirm your advise, so I'll give it another try tonight.

Cheers!

NP, its what I do, hope your fan is the same as the 'standard'.

 

[djii]

Your fan looks like a OEM and could be anything but likely will follow the diagram you found. You should get full speed by putting 12v across pins/wires 1 and 2.

You may have to short 4 and 2 but usually it's open for full speed.
Good luck.

 

[pinkfloyd4ever]

HELL YESSSSSSSS!!!!! Another one lives!!! My brand new baby is happily stirring the crap out of 750ml of water as I type. This calls for a beer! God I'm f'ing giddy..give me some bottle conditioned beer to start some yeast from...oh wait, maybe i'll finish that mostly-full growler of Schlafly's awesome limited release draft-only Burn Ward wheat [a hoppy American wheat] and kill 2 birds with one stone :rockin::rockin:

 

[camiller]

Finally got mine done, thanks for the inspiration Anthony!

https://www.homebrewtalk.com/f51/my...ir-plate-build-nearly-no-tools-needed-186481/

 

[DrinkNoH2O]

Question about the initial circuit design - should pin 1 (the furthest left pin in the picture) of the potentiometer be connected to ground or coupled with the output pin (middle/pin 2)? It appears that in this design it's not connected to anything.

 

[Anthony_Lopez]

That pin is for ground, but it is not really needed in this circuit.

 

[pinkfloyd4ever]

It doesn't need to be connected to anything

 

[T2P]

Well I tried this out and after several days still am unable to get it working. I managed to get everything on the list at the start from RS and a 12v fan, 9v charger and 2 of the curved HD rare earth magnets. After getting the wiring set up so the fan works, is adjustable and the power is operable I decided to give it a go. The washer I used was the biggest they had at 1.5".

Using two magnets in an "S" pattern or one on each rim of the washer would not spin the bar. This was the case regardless of how far I moved the flask away from the fan or speed. Also, even if the plastic lid was between the fan and flask the bar would not spin.

One of the magnets broke now too so that is scrap. I am not sure where to go from here. Ideas anyone?

 

[camiller]

Well I tried this out and after several days still am unable to get it working. I managed to get everything on the list at the start from RS and a 12v fan, 9v charger and 2 of the curved HD rare earth magnets. After getting the wiring set up so the fan works, is adjustable and the power is operable I decided to give it a go. The washer I used was the biggest they had at 1.5".

Using two magnets in an "S" pattern or one on each rim of the washer would not spin the bar. This was the case regardless of how far I moved the flask away from the fan or speed. Also, even if the plastic lid was between the fan and flask the bar would not spin.

One of the magnets broke now too so that is scrap. I am not sure where to go from here. Ideas anyone?

What is the size of your stir bar? Try one magnet, put the bar on the magnet to find where it lines up and center at that point:

 

[T2P]

What is the size of your stir bar? Try one magnet, put the bar on the magnet to find where it lines up and center at that point:

It is a 2 inch stir bar.

 

[camiller]

It is a 2 inch stir bar.

A lot of people have problems with longer stir bars. Still try the single magnet. I think trying to use two of the hard drive magnets gets real finicky because the axis of magnetization tends to be a straight line through the long axis. Using two of them in any configuration might work sometimes but you have to make sure you know which poll is where. Otherwise, get some small button sized magnets where the face of the magnet is one poll or the other.

 

[AlchemyBrewing]

Power problem? I have a 5V phone charger and a 12V computer fan. I can't seem to get it to spin the fan at all. When I take the fan and attach the red and black to a 9v battery it practically wants to fly off the table. The phone charger also has a thing white wire on it that I am guessing is the ground. Is it necessary to get it to power the fan? Please help... must get starter going this week! Alt bier is in the works.

 

[AlchemyBrewing]

...furthermore when I get the fan powered up with the battery and rheostat I can't get the stir bar to do much more then jump around and never actually spin. How can something so simple be so frustrating. I must be a dolt! Thanks for the help!

I also checked and my rheostat is a 10ohm jobber because I thought that was what someone else on here had. Will it make that big of a diff on this project from the 25ohm unit?

 

[T2P]

Ok so this is what I did. I went ahead and dropped the stir bar on the magnet and marked where the center of the bar met up with the magnet. I then put the magnet on the fan so the mark matched the center of the fan. After putting the assembly the bar appears to be getting thrown off of the magnet and basically sits at the outside edge of the field jitterbugging around. I found that if I turn the dial down all the way and then turn on the power, if the bar is above the fan/magnet, the fan will not start spinning. Turning the dial all the way up from the start makes it spin with the magnet on.

Is it possible that the washer I have is interfering because it has a fairly large hole in the center? It is a 1.5 diameter washer with 0.5 to 0.75 inches open in the center.

When you talk about the button sized magnets can they be black ceramic ones from home depot or something or do they have to be rare earth ones? I went to radioshack and all they had for rare earth were ones the size of a pencil eraser. The guy at the counter said they were regulated or something because they can wipe hard drives but that sounds like bunk to me.

 

[T2P]

Last update with some new progress. I think I have been able to get the magnet to at least stay in the center and possibly spin. It is not enough to create any vortex though, just some bubbles on the surface of the starter in the very center.

The axis of the HD magnet was about 2/3 towards one side of the length of the magnet so in order for it to be balanced I added a small nut right next to the magnet. I also brought the fan as close to the underside of the plate as possible but still no luck for the vortex.

Is the magnet too weak? Is the fact that I had to add the nut to balance it out slowing the fan too much possibly?

Ideas for where to go now?