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Here is my $20.00 Stir Plate. It about an hour to build. I did my first starter on it this last week and just pitched the Yeast. It seems to worked great. I used a 10K ohm POT, not much control. If I was doing it again I would change to 100 ohm.

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poislb said:
Mines a 2 inch bar, but as ya can see the center has that hump. I guess it creates less friction somehow and lets it spin more freely. I have the 3/8 earth magnets i bought from harbor freight, I use 2 on each side stacked. Try moving the magnets farther apart, that might help. Im now using a 7.5 volt adapter 200ma. Got any pics? how far are the magnets from the base, maybe wanna try getting it closer to the base to give more surface contact, without it hitting of course.
Click to expand...

Well after a very frustrating weekend of playing with magnets (should have been brewing). I finally figured out that the 5 dollar ebay spin bar I got just wasn't working for me. If I dropped a nail or screw or anything else in the flask it would spin just fine! I tried spacing magnets further apart or closer together, changed magnets, voltages, spacing up and down and on and on... It just wouldn't do anything but bounce the stupid stir stick around or throw it to the side.

I finally found this page and built my own spin bar out of 5 small earth magnets and some tubing and sealed the ends closed. Dropped it in and it spins perfectly now.
http://kbcbeer.com/stirplate.html

I ended up scraping the router shell in the end as I didn't like the way the flask sat on it with the top of the router being curved etc..

Final build:

12 Volt 80mm fan (had laying around)
1 hard drive magnet placed just off center
8 Volt DC wall adaptor (from an old logitech remote charger)
Lid from Droid Razr Maxx box
2000ML Flask only 15.95 at LHBS that's cheaper then I found online
5 neodymium rare earth magnets for the homemade stir bar


I do have a question. Are stir bars supposed to be magnetic? Or just have metal in them? This one I got on Ebay acts like it has a super weak magnet in it maybe? It won't even hold itself to the refrigerator..

Thanks all.. Here are a few pictures of my now working stir plate :rockin:

2012-11-11_22-28-14_254.jpg


2012-11-11_18-38-36_628.jpg


2012-11-11_22-27-53_354.jpg
 
I also purchased my Stir Bars from eBay. I received 5 of them in the lot that I bought. When I first played with my Stir Plate I did have the Bar I was trying keep flying off, even when running the Fan at a very slow speed. I thought that something was wrong with they way I had set everything up. Come to find out, that particular Stir Bar was not as magnetic as the rest. I have no problems running the Plate at full speed with the other 4 Stir Bars.

Yes they are magnetic, and all of them stick to the Refrigerator. At least the ones that I bought ( I have never been around others so all I can attest to are mine). They in fact are pretty strong for what they are. If you are using strong Rare Earth Magnets you might try lowering the fan in the box, or not using as may Magnets (stacked up). I found when building mine that bringing that magnetic field further away from the actual Stir Bar made thing much better. With the opposing poles on the two Magnets glued to the fan, I think the field was so strong when it was so close to the Stir Bar that it was causing problems. At least that is my hypotenuse with complete and total unfounded scientific backup (really just a guess). Mine worked much better with about a 3/4" gap between the fan and the were the Stir Bar sits. Good luck.
 
adamreef said:
BFG,

My build is almost identical to yours (same box & fan), but mine keeps throwing the stir bar. I have tried s hard drive magnet and 3/8 round neodymium magnets with various spacing. What did you use? How much space between the magnets and the back side of the lid of the box?

Thanks!

Adam
Click to expand...

Hey Adam -

Sorry it took me a while to get back to you, I've been out of town on business...

Anyway, this is my parts list below:

1"Magnetic Stir Bar Plain PTFE 6 x 25mm
1"Thermaltake Mobile Fan II External USB Cooling Fan - Us"
1"N45 Dia 1/2" x 1/16" Disc , Package of 10 Rare Earth Neodymium Magnets"

The rare earth magnets I spaced about about an inch or so apart. Essentially they are on either side of the middle circle in the fan, if that makes sense. Sorry I don't have a picture of the inside, perhaps I can get one this weekend when I get back home if it helps. I think I used 3-4 on each side. Getting the fan close enough to the lid of the box was the trickiest part for me. Basically I took the screws that held the fan guards on and drilled through the lid and suspended the fan with them. In order to do that, the fan is hanging a bit and the screws go through the lid and through the first set of holes on top the fan such that the fan is hanging from the lid and is just low enough so that the magnets are not hitting the lid when they spin. I tried to get it as close as possible and it seemed to work.

The only problem I have is it doesn't like to stay on full power without throwing the stir bar. I will try to adjust this in the future, but for now I leave it on about half power which keeps everything stirring nicely and is probably ok. I'm not sure if that helps at all, if you need more help shoot me a message and I'll try to explain it a little better or send you a picture this weekend when I get home. Cheers! :mug:
 
Spargeking said:
I also purchased my Stir Bars from eBay. I received 5 of them in the lot that I bought. When I first played with my Stir Plate I did have the Bar I was trying keep flying off, even when running the Fan at a very slow speed. I thought that something was wrong with they way I had set everything up. Come to find out, that particular Stir Bar was not as magnetic as the rest. I have no problems running the Plate at full speed with the other 4 Stir Bars.

Yes they are magnetic, and all of them stick to the Refrigerator. At least the ones that I bought ( I have never been around others so all I can attest to are mine). They in fact are pretty strong for what they are. If you are using strong Rare Earth Magnets you might try lowering the fan in the box, or not using as may Magnets (stacked up). I found when building mine that bringing that magnetic field further away from the actual Stir Bar made thing much better. With the opposing poles on the two Magnets glued to the fan, I think the field was so strong when it was so close to the Stir Bar that it was causing problems. At least that is my hypotenuse with complete and total unfounded scientific backup (really just a guess). Mine worked much better with about a 3/4" gap between the fan and the were the Stir Bar sits. Good luck.
Click to expand...

Yes, you are correct that lowering the box with earth magnets help a ton. Also I found out that a 50 or 100 ohm rheostat potentiometer works a hell of alot better that the suggested 25 ohm. Hook that up with a 12 volt power supply and ya can really dial in the speed like a true lab stir plate...At full bore I never throw a bar with a 2000 ml starter..
 
LoloMT7 said:
Well after a very frustrating weekend of playing with magnets (should have been brewing). I finally figured out that the 5 dollar ebay spin bar I got just wasn't working for me. If I dropped a nail or screw or anything else in the flask it would spin just fine! I tried spacing magnets further apart or closer together, changed magnets, voltages, spacing up and down and on and on... It just wouldn't do anything but bounce the stupid stir stick around or throw it to the side.

I finally found this page and built my own spin bar out of 5 small earth magnets and some tubing and sealed the ends closed. Dropped it in and it spins perfectly now.
http://kbcbeer.com/stirplate.html

I ended up scraping the router shell in the end as I didn't like the way the flask sat on it with the top of the router being curved etc..

Final build:

12 Volt 80mm fan (had laying around)
1 hard drive magnet placed just off center
8 Volt DC wall adaptor (from an old logitech remote charger)
Lid from Droid Razr Maxx box
2000ML Flask only 15.95 at LHBS that's cheaper then I found online
5 neodymium rare earth magnets for the homemade stir bar


I do have a question. Are stir bars supposed to be magnetic? Or just have metal in them? This one I got on Ebay acts like it has a super weak magnet in it maybe? It won't even hold itself to the refrigerator..

Thanks all.. Here are a few pictures of my now working stir plate :rockin:
Click to expand...

Perfect. I have a Droid box sitting around too.
 
brew2enjoy said:
Perfect. I have a Droid box sitting around too.
Click to expand...

I gotta say I'm really happy with this stir plate now but it took me a lot of screwing with to finally figure out it was the stir bar that was the problem. I mean seriously who would have guessed that? My buddy brought his stir bar over last night we dropped it in and it worked fine. Tried mine and it still wouldn't work. Yes they are exactly the same bar both 2" inch with the center ring on them. Go figure that out. But I'm perfectly content using my homemade stir bar and can't wait to get back to brewing now.

For the final test I sent him home with my stir bar to test on his stir plate. All I got was a txt message that said "Well it's not just your plate man I threw it away" :mug:
 
Yeah, I am pretty bummed as a cowboy fan. But then again, I am used to it. Nothing will change 'till Jerry released the GM role to a competent individual.

Did you get the pun?
 
LoloMT7 said:
Cool glad it worked out for you.

:off:
Nice coaster by the way! This is my tap handle i bought from a guy on ebay
Click to expand...

well, I haven't tested it out yet because I don't have a stir bar, but it seems to spin pretty good when I put a screw on it.

Nice tap handle! :mug:

Huaco said:
Yeah, I am pretty bummed as a cowboy fan. But then again, I am used to it. Nothing will change 'till Jerry released the GM role to a competent individual.

Did you get the pun?
Click to expand...

yeah, I got it :mug: Vick's days in Philly are numbered thankfully. It's time to move on and see what Foles can do.
 
Finally had time to build mine today. I ended up spending more than I would've to just buy a stir plate but whatever. This one is waaaaaay classy...

IMG_20121120_131114.jpg


IMG_20121120_131254.jpg


The speed control knob is actually countersunk into the box. The box was too thick to mount the rheostat so I had to use a forstner bit to make the area thinner.

IMG_20121120_131320.jpg


IMG_20121120_131406.jpg


The build was expensive because I ended up buying a brushless motored fan. Whisper quiet...
 
Gitmoe said:
Finally had time to build mine today. I ended up spending more than I would've to just buy a stir plate but whatever. This one is waaaaaay classy...

IMG_20121120_131114.jpg


IMG_20121120_131254.jpg


The speed control knob is actually countersunk into the box. The box was too thick to mount the rheostat so I had to use a forstner bit to make the area thinner.

IMG_20121120_131320.jpg


IMG_20121120_131406.jpg


The build was expensive because I ended up buying a brushless motored fan. Whisper quiet...
Click to expand...

GREAT build!!! What is your connection on the backside of the cigar box?
 
Jester said:
GREAT build!!! What is your connection on the backside of the cigar box?
Click to expand...

I put the power switch on the back. Wanted the front to look as clean as possible. Making it look good was the only way my wife would let me keep it on the counter...
 
Nothing fancy but the usual computer fan and magnets along with parts from radio shack. My jug has to be off center to get a full vortex. Could be my 9 V power supply. Not enough juice.

Nice looking plates everyone. Very creative.

View attachment 85328



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2012-11-01 08.26.05.jpg
 
This may seem like a dumb question... has anyone ever tried using a casing that is itself a ferrous (magnetic) material? My mind can't quite parse out whether it would interfere with the attraction between the stir bar and magnets.

The reason I ask is that I have a fried guitar pedal that would make a perfect casing. I'd rather figure out the casing before sourcing the other materials. To be specific, I have one of these:

holier-grail.png
 
JeffersonJ said:
This may seem like a dumb question... has anyone ever tried using a casing that is itself a ferrous (magnetic) material? My mind can't quite parse out whether it would interfere with the attraction between the stir bar and magnets.

The reason I ask is that I have a fried guitar pedal that would make a perfect casing. I'd rather figure out the casing before sourcing the other materials. To be specific, I have one of these:
Click to expand...

Mine is made out of a medal box as well and I ended up just cutting out a hole where the magnets spin at because I couldn't find magnets strong enough to go threw the medal and turn the stir bar. You can always try using it and if it doesn't work use a whole saw and cut a circle hole in the top.
 
Got around to building my stir plate. A standard LM317 build with an on/off switch.








There's an 80mm computer fan which as a piece of 1" schedule 40 PVC hotglued to it with some rare earth magnets on it. I've dremeled out some holes (melted out, really) for the magnets using a cutting wheel and then secured the first magnet with hot glue. The rest stay by themselves. The speed is controlled by an LM317 with a 330 ohm resistor going from OUT to ADJ and a 10k ohm audio taper potentiometer with on/off switch. I can control power on/off and get anywhere from around 3V to 11.5V out to the fan. The power connector is a standard kobiconn 2.1mm barrel jack from Mouser, but the rest of the parts are from Radio Shack. The box is a 6x4x2 project box from Radio Shack as well.

One problem I ran into was putting too many magnets on the fan. With 4 magnets the 1" stir bar would not spin at all. I think the friction of the bar pulled so hard against the device would just prevent the fan from spinning at all. 3 works great, doesn't throw the bar at even the highest speed, and is silent at low speed with a dimple being pulled into the starter.
 
Just finished mine yesterday...

Bare bones - 93mm fan, couple of rare earth magnets, rheostat, 5v cell phone charger.



image-1789100845.jpg
 
$1.99 box from Goodwill.
Master switch left over from some idea I had for my boat.
$0.99 12V power supply from Goodwill
Pot bought off Amazon = too much after shipping and handling, but at the time it was the only way I could buy one.
$8 (?) for a 10 pack of rare-earth magnets from Amazon and a fan from a computer I don't use anymore.

IMGP2525.jpg
 

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