My homebrew stirplate

[MrSaLTy]

Good god! We've created a monster. nice work man.

 

[edost]

That's fantastic Yuri... keep up the great work!

 

[Yuri_Rage]

Ok, final update on the stirplate production project. I have 9 of these things ready to ship. Those who sent me a private message already can expect a reply concerning payment details. Anyone else interested, now's the time to send me a message!

 

[Yuri_Rage]

One more thing: I can't include a stir bar with the stir plates - you'll be on your own for those. Sorry about that!!! Here are some links where you can find them online:

morebeer.com
eBay (search magnetic stir bar)
Lab Scientific - check out the prices of their stir plates - $165 to $1125!!!


Here's a pic of the finished product:

 

[EdWort]

Sweet! Great work! You have a cottage industry going here Yuri. Money's on the way.

Gadgets, gadgets, I love gadgets!

 

[Yuri_Rage]

Gadgets, gadgets, I love gadgets!

Next on the list of gadgets is a homemade grain mill. Thinking of a single roller design (1" steel round bar stock - knurled and maybe powder coated) with an adjustable crush plate. I doubt I'll make more than one complete mill, but, depending on the results, I might be able to make a few extra rollers.

 

[chillHayze]

Paypal sent!

 

[Desert_Sky]

Paypal sent!

!!!mí también!!!!

Thanks Yuri

 

[Yuri_Rage]

Here's a list of part numbers and prices from www.jameco.com. You can probably find a cheaper/smaller perf board (circuit board) than the $14.95 version I ordered. Everything but the magnets and a few machine screws is included in the list below. The magnets you can get from an old hard drive, eBay, or a lab/scientific supply store.

ITEM......DESCRIPTION.....................PRICE
163619....FAN,12VDC,90CFM,4.68"sqX1"......$4.46
211051CM..TRANS,WALL 12VDC/800MA..........$2.19
297553....CONNECTOR,POWER,PC712A..........$2.77
23579.....IC,LM317T VOLTAGE REGULATOR.....$0.39
615312....HEAT SINK,SILICONE,6.5,GRM......$2.29
158051CM..HEAT SINK,.750"X.520"X.375".....$0.35
105161CM..PROTOTYPE BUILDER,3.6"x7".......$14.95
265076CM..KNOB,1/4" SHAFT,14.6MM,JK-905C..$0.73
18868CM...CASE,INSTRUMENT,7.9"x6.3x2.5....$7.10
316013CM..SWITCH,ROCKER,R13-66A-B-02......$0.86
637183CM..LED,PANEL MOUNT,GREEN...........$1.05
94160.....CAP,RADIAL,MINI,5MM,1uF,50V.....$0.12
15270.....CAP,CERM,DISC,.1uF,50V,20%......$0.15
29663.....RESISTOR,1/4W 5%,1.0K OHM,......$0.99
255521....POT,10K,RV24A-10-15R1-B10K......$1.19

 

[Pumbaa]

glad I found this. I just finished my fermenting chamber and am gonna make some cider but I could only get a 50ml smack pack so I'm going to need to make a starter and have been thinking of making a stirplate . . .

We need a new forum for projects:rockin:

 

[Walker]

We need a new forum for projects:rockin:

Or at least a sticky thread with link to "How to Build/Modify your own _____".

where _____ is stir plate, chiller, kegerator, etc.

 

[BrewStef]

I finally got my stirbar for Yuri's awesome stirplate. Works like a charm. The only issue is that it is hard to center my 2L Erly, but perhaps that is not critical? I cannot get the vortex like in the pictures, but it does create enough movement where I get lots of aeration and stirring...yeast never settles completely and I get lots of bubbles.

Awesome job Yuri!

BrewStef

 

[Teedocious]

I just finished my stir-plate beta. Total cost: $6.50. I had a computer fan laying around as well as an old 12v cell phone charger. (My gf works in a lab & got me a 2" stir-bar for free) Parts I bought: rare-earth magnets ($3.50 at ACE - called super magnets & overpriced) & a 500ohm pot ($3 at Radioshack and way overpriced). Right now I have the flask sitting on two books but the sucker is plugging away. A project box made at TAP plastics shouldn't cost more than $5. Has no power button - just plug in & turn pot. (It'll never be plugged in when not going anyway, so why bother.) As far as the LM317 - I didn't use one - I figure if I need to replace the $5 fan every year due to the extra wear I'll still live. (I probably used $.05 of solder as well.) Total cost can't possibly be over $15.

Freaking sweet. Super starters... here I come. Tomorrow I finish it & make a starter...

 

[pbowler]

Sorry to interrupt, but this may be helpful.

variable speed Case Fan
http://www.newegg.com/Product/Product.asp?Item=N82E16835220013

looks like 90% of the work is done already

$17

 

[Teedocious]

The work is sorta done for us (don't forget to add the $5 for shipping = $22). You still need to get from the molex computer power supply connection to a 12v dc power supply. Still need to have an adapter for that, still need to solder it up, still need to find a box to put it in... etc. And since you gotta do that anyway, you can just buy a fan ($5) and a pot ($3) without any shipping and spend 10 minutes hooking them together and you're in the same place as you are with that fan.

btw: I set my "beta" up this morning - went to work, came back 10 hours later & it was still purring. The first starter is in there as we speak for a Sunday brew...

 

[snaproll]

I haven't checked mine out to be sure but it would seem to me that 800 rpm is a bit high. Any input here??
I could be full of beans too !!

 

[pbowler]

I haven't checked mine out to be sure but it would seem to me that 800 rpm is a bit high. Any input here??
I could be full of beans too !!

Yeah, that was my only thought. I'm not really sure at what speed the stirplates spin.

anyway, just a thought.

 

[Teedocious]

I'm not sure how fast either - but pretty slow.

Mine is going right now - if the stirbar spins off and it's not working the fan revs up to very high RPM - but when the resistance is there to spin the brar through the water/starter, the thing probably only spins a couple hundred rpm at most. (pretty hard to tell though by just looking at it.)

So the 800 RPM variable fan should be fine - because it'll just spin slower with the resistance. - but for the price and the work that remains to be done still... not worth it.

 

[Dude]

Stir plate gurus....

I bought the guts of a stir plate from someone on anothe rboard before you guys did this. I still haven't put it together.

I recieved 2 potentiometers with the kit, along with a fan, magnets, and a power supply.

Supposedly I'm supposed to use both of the potentiometers. Any reason why, you think? Should I just copy your design instead? I figure I'd only need to buy a few dollars worth of extras.....

I have everything ready to go, including the project box, but I'm not sure why I got two potentiometers. Any input?

 

[Chairman Cheyco]

Some stirplates are heated, might that be the reason for the other?

 

[Dude]

Some stirplates are heated, might that be the reason for the other?

No.....

In his (vague) instructions, supposedly I turn one of them full tilt and then adjust the speed with the other one until the magnet/vortex/speed is correct. I dunno.

I'm clueless on this stuff.

FWIW, their is no switch involved, only two knobs connected to the potentiometers that control the spinning of the fan.

 

[Pumbaa]

No.....

In his (vague) instructions, supposedly I turn one of them full tilt and then adjust the speed with the other one until the magnet/vortex/speed is correct. I dunno.

I'm clueless on this stuff.

FWIW, their is no switch involved, only two knobs connected to the potentiometers that control the spinning of the fan.

Sounds like they just replaced the switch with another potentimeter. I dont see why the set up you describe wouldnt work.

FWIW I am just about finished with my stirplate. I went with the 12v 120mm mufin fan, a 6 volt power supply, a switch, a potenimeter, and I added a small 12v light just so I have verification the switch is working. I have all the conections soldered in EXCEPT the power suplly and I think I will leave that unsoldered for now. Right now with the 6 volt power supply I dont get fan movement until about half power. At half power the fan wobbels back and forth and I get spin just past half. Since I have a very cheep source for power supplys ( http://www.sciplus.com/category.cfm?subsection=13&category=137 )I may go spend another $6 and get a 9v and a 12v and experiment. I DO NOT have my magnets expoyd on yet since I am paranoid and am waiting for my stir bar which should get here Tuesday. I just want to make sure the magnets I have will work.

Soon at I get the last few bits and do some experimenting I'll let ya know what I find out

 

[MrSaLTy]

Stir plate gurus....

I bought the guts of a stir plate from someone on anothe rboard before you guys did this. I still haven't put it together.

I recieved 2 potentiometers with the kit, along with a fan, magnets, and a power supply.

Supposedly I'm supposed to use both of the potentiometers. Any reason why, you think? Should I just copy your design instead? I figure I'd only need to buy a few dollars worth of extras.....

I have everything ready to go, including the project box, but I'm not sure why I got two potentiometers. Any input?

Dude, it may just be that there are 2 pots to provide more resistance. It depends on the Ohm ratings on the pots and maybe he figured that one would not give enough resistance to adjust it correctly. Id just do some trial and error with them before you solder anything and see if you can get away with one. If not you could use both or just go to ratahack and get one with a higher Ohm rating. He also may be using 2 to account for the wattage ratings of one may not be enough to dissipate the heat if you are using 12v. If its 6v then it probably won't matter and it may not even matter for 1 at 12v if the pot is rated high enough.

 

[Teedocious]

No.....

In his (vague) instructions, supposedly I turn one of them full tilt and then adjust the speed with the other one until the magnet/vortex/speed is correct. I dunno.

I'm clueless on this stuff.

FWIW, their is no switch involved, only two knobs connected to the potentiometers that control the spinning of the fan.

The two pots are supposed to be connected in-line (one after the other). Pretend you are hooking up one pot, then instead of taking the live wire to the fan itself, take it as a source to the second pot. Then go from the second pot to the fans hot wire.

Theoretically this should cause the upstream pot to be a rough gauge of power, and the downstream pot as a fine adjustment tuner.

In reality though (at least my reality) - one pot is just fine. I don't have a power switch, I just plug in & turn the pot until the thing spins. Couldn't be more simple. Only variables I have are how many magnets to use (I can get action with two or four) and how high the flask needs to be from the magnets.

If I were you Dude - just hook up one pot and see if it works. I bet it does and you'll never know that you should be missing your second pot. (Christ, if the power supply in low enough wattage, you might not even need a pot...)

 

[BBboomer]

Ok, final update on the stirplate production project. I have 9 of these things ready to ship. Those who sent me a private message already can expect a reply concerning payment details. Anyone else interested, now's the time to send me a message!

I would like one as well.
I don't use PayPal so can I send you a check?

 

[boo boo]

Nice. Glad I found it as I'm in the process of building one myself.

Lots of great info here.

 

[Yuri_Rage]

Alright, alright, I'm tired of disappointing those of you who want to buy one of my stir plates, so I'm back in business!

I've made some improvements, ordered the parts, and I should have some completed stir plates within a couple of weeks (LEDs are backordered). Parts are on order for 10 of them, but I don't plan on turning anyone away. If there are more than 10 interested brewers out there, I'll make some more!

I proved that my "new and improved stir plate" is just that tonight. A list of improvements:

"Off the shelf" speed controller (modified "Yuri style" to allow RPMs below 300)
Stronger magnets to keep bigger stir bars in place at higher speeds
Better DC transformer connectors
A 1" stir bar will be INCLUDED

Here's a pic of the two extremes in stirring speed range. That's a 2" stir bar in a full 1 liter flask. Note the one on the left barely has a dimple on the surface.

Now for the bad news: I have to raise the price. I'm going to ask $60.00 (priority shipping to anywhere in the US is INCLUDED). That's still less than half of what a new laboratory supply house stir plate costs!

Thanks again to all of you who have expressed interest! Private message me to work out the details. I won't accept payment until I have a stir plate ready to ship to you.

 

[dantodd]

"Off the shelf" speed controller

So what controller did you end up changing to?

 

[Yuri_Rage]

So what controller did you end up changing to?

It's a very similar circuit to the DIY version posted here from a company called Rosewill (for CPU fan control...of course). I beef up the resistance by a factor of over 10 in part of the circuit to get the RPM range that I want.

 

[dantodd]

Thanks. I have fans, wall warts, discreet components and rare earth magnets just thinking about maybe buying a regulator rather than building my own.