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

[forcabrew]

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[ACESFULL]

Maybe I will snap mine in half and give it a try. Worse thing that could happen is that I need to by magnets. The thing that kills me is that the magnets are wicked cheap but then they rape you on the shipping. A $2 magnet costs $8 to ship. That doesn't make sense.

Go to Ace Hardware that is if you have one near you and get these. They work great and the are much cheaper than they are listed here. I got 2 packs for $6 out the door and my 2" stir bar pulls a helluva cone to the bottom of the flask.

http://www.acehardware.com/product/...0.2628078.1259402&lmdn=Brand&searchId=1259402

 

[rlynge]

I just got some from KJ magnets and let me tell you those are some strong magnets. I just have to make a trip to the hardware store and I should be done with this build some time this week!

 

[mredge73]

I thought that I would post what I bought today to build my stir plate.

I bought this fan (Comes With Fan Controler!!!)
http://www.newegg.com/Product/Product.aspx?Item=N82E16835200020

$7.99 - $1.59 (Discount Code BTEKAJA22) + Free Shipping = $6.40

 

[Flomaster]

I thought that I would post what I bought today to build my stir plate.

I bought this fan (Comes With Fan Controler!!!)
http://www.newegg.com/Product/Product.aspx?Item=N82E16835200020

$7.99 - $1.59 (Discount Code BTEKAJA22) + Free Shipping = $6.40

This is the way to go. Not sure why more people aren't going this route. I tried the make shift power supply and fan route, but it just didn't work out for me.

-=Jason=-

Sent from my HTC Incredible using Home Brew talk

Edit: I bought a fan off Amazon.com it uses USB for power do your don't need some special 12V power supply.
http://www.amazon.com/dp/B00080G0BK/?tag=skimlinks_replacement-20

 

[camiller]

This is the way to go. Not sure why more people aren't going this route. I tried the make shift power supply and fan route, but it just didn't work out for me.

-=Jason=-

Sent from my HTC Incredible using Home Brew talk

Edit: I bought a fan off Amazon.com it uses USB for power do your don't need some special 12V power supply.
http://www.amazon.com/dp/B00080G0BK/?tag=skimlinks_replacement-20

I just used bits and bobs I already had laying around except a $4.99 case fan I bought new locally at a shop I drive past daily anyway so no shipping cost. I have substantially more spare 12v power supplies laying around (although I used a multi-voltage power supply I had laying around) than special 5v ones with USB sockets and I don't do my starters in the office with my computer so that is why I didn't go that route.

The important thing is there are more ways to skin this cat then there are cats and everyone should do what works for them.

 

[heckels]

I thought that I would post what I bought today to build my stir plate.

I bought this fan (Comes With Fan Controler!!!)
http://www.newegg.com/Product/Product.aspx?Item=N82E16835200020

$7.99 - $1.59 (Discount Code BTEKAJA22) + Free Shipping = $6.40

so do you just pick up a 12v power adapter like this one and hard wire that puppy? http://www.newegg.com/Product/Product.aspx?Item=N82E16812125018

 

[Flomaster]

I just used bits and bobs I already had laying around except a $4.99 case fan I bought new locally at a shop I drive past daily anyway so no shipping cost. I have substantially more spare 12v power supplies laying around (although I used a multi-voltage power supply I had laying around) than special 5v ones with USB sockets and I don't do my starters in the office with my computer so that is why I didn't go that route.

The important thing is there are more ways to skin this cat then there are cats and everyone should do what works for them.

I guess I wasn't as fortunate. The fans I had on hand burnt out, none of my power supplies would turn the fans I had. When I did find a combo that worked the slowest setting was still way to fast

-=Jason=-

Sent from my HTC Incredible using Home Brew Talk

 

[hungrymonkey]

Just built one today. OP saved me about $110 from what the LHBS was selling them at.

I did have to monkey with the magnets a bit. Ended up using both the magnets I salvaged from the old HDD.

 

[Accidic]

I think speed can be almost anything so long as the magnets are strong enough. My old plate would go full speed once I got it balanced. It was 2900ish rpm in the case so with weight it was probably 2500+. My current had an external rpm control but the base fan is slower (2400rpm) which is fine cause I didn't have anymore scsi drive magnets. It will turn full speed (shows 1920-1960ish) but I still don't have it remotely balanced. It will also turn without throwing containers up to about 7/16ths thick without losing the bar which is good because the fan doesn't seem to be adjustable.

 

[ekjohns]

for a sub $10 box people should look at lock cash boxes. They are metal so they can hold a good amount of weight, are big enough to have lots of room to mess around in and are cheap.

http://www.sears.com/shc/s/p_10153_...19x00001a&ci_src=14110944&ci_sku=SPM241831844

 

[bbognerks]

They are metal so they can hold a good amount of weight

Metal top and magnets, probably not a good combo. But hey, maybe it's aluminum (doubt it).

 

[ekjohns]

I was thinking along the lines of cutting out a hole over the fan to allow easy access to the magnets if you need to adjust spacing and height. Then there will not me metal over the magnet

 

[hopsalot]

10-4 wth the part list anyone can do this! Thanks to the Builder and HBT!

 

[Flomaster]

I was thinking along the lines of cutting out a hole over the fan to allow easy access to the magnets if you need to adjust spacing and height. Then there will not me metal over the magnet

I have a hole in my lid do I could raise the fan up higher

-=Jason=-

Sent from my HTC Incredible using Home Brew Talk

 

[KES]

Just got my 1000ml flask and stir bar today. The stir plate works great. Thanks for the excellant tutorial.

 

[DarkPhyre]

just finished my stirplate. I have a 1" stirbar and 2000mL flask. After tinkering w/the magnets (how do magnets work?!?!?!? ) I got it to work flawlessly. brings a strong vortex all the way down on a full flask.

I used home depot magnets for 2.19 a two pack. rectangle shape.

 

[Accidic]

Sounds like you got it right. If serious about the magnet question (sorry I don't do sarcasm early) the magnetics place people have linked to as a good place to buy magnets (k&j magnetics or something like that) throughout the thread has some good write-ups about the poles and fields. You want north on one side, south on the other. It's why hd magnets can be hard to use as their not all magnetized axially.

 

[StirStarters]

www.magnet4less.com is also a good place for magnets, they have a large variety of shapes and sizes. I use the 1/8" x 3/8" button style magnets, 2 for each stir plate.

+1 to Accidic, it's important to get ones that are polarized axially. In my case, through the 1/8" dimension.

 

[Nieuwoldm]

Just finished my stirplate and it works awesome. Well kinda I need to source a higher voltage power supply, I started with 4V then stepped to 5V which works but I would like more power. Stupid me cleaned out my tangled mess of old power cords about a month ago.

But that being said Thanx a bunch to the OP really saved a lot of money.

 

[Homercidal]

My LHBS gives away free cigar boxes. They look nice and you can find them for a couple of bucks on ebay. A hole saw would work very well on them as well.

 

[jaredkent]

I just built mine yesterday. Slight problem, though. Everything works fine, fan spins, rheostat regulates the speed, power switch works... but my fan isn't spinning fast enough. I am using a 5V 310mA Power Supply. What Amperage are you guys using. The voltage shouldn't play a part in the amount of power that is going to the fan, that is determined by the amperage. I just found a a 5V 700mA PS so I'll solder that tomorrow and test it out.

The problem this is causing (and maybe I'll film it and post it tomorrow) is the fan either refuses to spin under the weight(?) of the magnet, without even putting the washer on. Give the fan a little flick and it will start up, but too weak. The other problem I have is, under the best situation I got, the stir bar would start spinning perfectly (this was rare) start creating a vortex (in about an inch of water in a 250ml flask) and as I increased the speed and it started getting about halfway to the bottom of the flask, the stir bar would be thrown. Does this mean the magnet isn't strong enough, in addition to my fan not putting out enough power?

I'm going to try and recreate these results and film it. Expect a video either later tonight or tomorrow afternoon.

 

[barrooze]

I had a similar issue with the ps not spinning the fan fast enough with my first assembly. I did end up using a more powerful ps and it now spins the bar just fine. I also had issues with my bar being thrown. I ended up using a washer that I have centered and on it is the magnet as centered as possible. The bar hasn't been thrown once ever since. My guess is you need a higher amperage ps and the mag needs to be centered more.

 

[jaredkent]

I had a similar issue with the ps not spinning the fan fast enough with my first assembly. I did end up using a more powerful ps and it now spins the bar just fine. I also had issues with my bar being thrown. I ended up using a washer that I have centered and on it is the magnet as centered as possible. The bar hasn't been thrown once ever since. My guess is you need a higher amperage ps and the mag needs to be centered more.

Found a 12v 900mA PS late last night. I hooked that up this morning and there is definitely more power now. I can get a nice 2L vortex, but it only reaches about halfway down the flask, is this a problem?

Another problem I'm having is adding the washer. I'm having a real hard time centering it. I've been testing it all out with duct tape first, before I glue anything down, and no matter how much I think I've centered it and the magnet, I get wobbles when I switch the fan on. I'm actually having better luck with just the magnet, and no washer, only problem is the short vortex as stated above.

3rd problem is that when the flask is on the stir plate, running, the fan runs slower than when I lift the flask off of it. Once I lift it off you can hear it speed up considerably. I assume this is because the fan is pushing a stir bar through 2L of water, and since it's still creating a decent sized vortex I wasn't too concerned.

My last problem is really just flask design. I have Pyrex flasks and they have a little bulge at the bottom of the flask. This causes the stir bar to be awfully noisey. Anyone else have this happen, and find a solution, or should I just learn to ignore the noise.

Thanks.

 

[Accidic]

In the case of the washer it may be more than it just being centered. Glue'ing a washer to the fan creates more weight at the top of the fan and depending on the fan's tolerances this can throw it off quite a bit on some fans. My previous fan worked fantastically and ended up so well balanced you couldn't even feel a vibration or hear a sound. My most recent model on the other hand... The fan seems cheaper and it was literally impossible to balance almost as if the balance point fluctuates a little bit when it was running to start with and adding the weight just exacerbates the situation. I finally just decided to live with a little vibration (I can get dozens upon dozens of replacements for free if it came to it) from it and go with it and it's been running just fine for months.

Personally if it were me I'd get it as close to smooth as you can and go with it. Unless you're using a big fancy fan with bells, whistles, and lights they're insanely cheap if you have to replace anyway.Alternatively I've toyed with the idea of mounting it to one of those little cheap AC fans you see at WM on closeout after summer for like $3 and putting a voltage divider in the circuit to adjust the speed. They're a lot better balanced and you can remove the steel fan and adjust the washer with a screw and two washers on the shaft to boot. Plus no wall wart = WIN~

 

[barrooze]

Found a 12v 900mA PS late last night. I hooked that up this morning and there is definitely more power now. I can get a nice 2L vortex, but it only reaches about halfway down the flask, is this a problem?

My last problem is really just flask design. I have Pyrex flasks and they have a little bulge at the bottom of the flask. This causes the stir bar to be awfully noisey. Anyone else have this happen, and find a solution, or should I just learn to ignore the noise.

Thanks.

That size vortex is just fine and if the bar isn't getting thrown, I'd deal with the noise.

 

[camiller]

...

Another problem I'm having is adding the washer. I'm having a real hard time centering it. I've been testing it all out with duct tape first, before I glue anything down, and no matter how much I think I've centered it and the magnet, I get wobbles when I switch the fan on. I'm actually having better luck with just the magnet, and no washer, only problem is the short vortex as stated above.
...

Apply power to the fan, touch the tip of a red sharpie near the center of the fan hub while it is spinning. Line the hole in the washer up on that small red circle/dot.

edit: Oh, if the fan wobbles on it's axis anyway, might need to get a better quality fan.

 

[Accidic]

It would take an incredibly unbalanced fan to knock over your starter and I would think the agitation won't really hurt anything and could possibly help on some small level so long as you're not throwing your stir bar. Mine's slightly off balance because of the fan and I can easily pull a solid vortex down to the bottom of a 1 gallon Kool-Aid/Tea pitcher. I can do the same with a 1/2 gallon jar with up to a 3/8" thickness bottom. Imbalance isn't the end of the world really as the spiral for your stir bar will be pretty steady either way. Just mount it well. I used an old computer speaker enclosure for a rock solid surface to boot.

 

[OHIOSTEVE]

built mine tonight....easy to do with these instructions. off to buy a bar and flask tomorrow

 

[theveganbrewer]

built mine tonight....easy to do with these instructions. off to buy a bar and flask tomorrow

Where are you getting the flask and bar locally? I was just going to get mine online cause I figured no one had the things here.