How to build a stir plate for less than ten quid

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Managed to find a fan and power supply so all parts are now on order. Really looking forward to making this. I would like to fit an on/off switch and presuming it can be wired in serial? Would the power be enough to drive a lit switch or am i better off with a rocker?
 
Managed to find a fan and power supply so all parts are now on order. Really looking forward to making this. I would like to fit an on/off switch and presuming it can be wired in serial? Would the power be enough to drive a lit switch or am i better off with a rocker?

If you get a 12v illuminated switch it'll work, though the light will dim as you turn the speed down.
Yeah just break the supply to the PWM through switch.
 
Here is mine. It still works as a cigar box too.
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I upgraded my stir plate from the soap box to a chocolate box. I found after a few uses the structural integrity of the soap box was rather compromised. It was sagging a little in the middle meaning the magnets were rubbing on the inside making a very irritating sound. Also it wasn't waterproof, so I had concerns about the starter overflowing onto it. I also couldn't get rid of the lavender smell from it which was annoying when trying to have a smell of the starter. The new one isn't as pretty but much more sturdy and made of plastic so should last a bit longer.



 
I love a good project and this looks fun to make. I might give it a go.

Here comes the stupid question of the day though... Brace yourselves... No, really....



What do you use it for? I get that it stirs the starter, but why? Can't you use a spoon?
 
I love a good project and this looks fun to make. I might give it a go.

Here comes the stupid question of the day though... Brace yourselves... No, really....



What do you use it for? I get that it stirs the starter, but why? Can't you use a spoon?

You can do that, I would recommend shaking not stirring. Less critters getting into your starter.
But the stir plate keeps the yeast in motion while feeding it oxygen. Lots and lots of oxygen. This makes the yeast want to replicate faster.
 
The good thing about using flasks are that you can mix and boil your starter wort right in the flask. This makes a perfect sterile environment.
 
I love a good project and this looks fun to make. I might give it a go.

Here comes the stupid question of the day though... Brace yourselves... No, really....



What do you use it for? I get that it stirs the starter, but why? Can't you use a spoon?

:lol: That's a pretty good question I'd say!
The point of the stir plate is to keep the yeast in suspension and to allow gas exchange in the starter wort, O2 in and CO2 out. This requires the starter to be kept in motion for at least 12 hours, sometimes up to 3 days if growing from a small amount of yeast.
 
Steve is right. I collect and keep a small amount so I build a starter over a week time.
 
:mrgreen:If you're a bit lazy like me another option is to simply buy a fan for a few quid, this cost me �£3 I think and then I just used an old magnet and the flask from a coffee cafetiere. It saves on time at least and costs next to nothing. It works on all three speeds and is stable.. Comes with rechargeable battery and a usb charging point. Does me fine :thumb:
Hi Amidared, does this system still work for you? Did you need to remove the middle part of the fan to be able to place the magnets inside? I have seen the same fan that you have used on eBay/Amazon and was considering the same system.
 
Hi Amidared, does this system still work for you? Did you need to remove the middle part of the fan to be able to place the magnets inside? I have seen the same fan that you have used on eBay/Amazon and was considering the same system.

Hi Ben, Yeah it works just fine, I removed the centre as you can see in the snaps, but not to fit the magnets, I just didnt like the look of the silly drawing on the plastic and thought the magnets would work better without the plastic piece in. Works fine really, cost a couple of quid and has a rechargeable battery and usb. I've done maybe a half dozen starters with it and had no problems once the magnet is centered. Welcome to the forum by the way :thumb:
 
Hi Ben, Yeah it works just fine, I removed the centre as you can see in the snaps, but not to fit the magnets, I just didnt like the look of the silly drawing on the plastic and thought the magnets would work better without the plastic piece in. Works fine really, cost a couple of quid and has a rechargeable battery and usb. I've done maybe a half dozen starters with it and had no problems once the magnet is centered. Welcome to the forum by the way :thumb:
Sounds successful! What tool did you use to cut the plastic from the centre? I received the fan from eBay and I thought a 1/2" drill bit could work but could end up going through the whole lot...
 
The good thing about using flasks are that you can mix and boil your starter wort right in the flask. This makes a perfect sterile environment.

I'd not thought about that! That sounds perfect, if it wasn't for that fact that I only have an electric hob...


I've just bought myself a 2l conical flask for making a starter. I'd thought a stirplate would be overkill for my setup, but I'm looking into overbuilding my starters to cut down my yeast costs, and some test calculations suggest that flask would be getting a bit full with just shaking, so I'm going to order the parts for this and give it a go. Thanks for posting the guide here.

One thing I did wonder is how you stop the stir bar accidentally falling into the wort. But you'd just keep an extra magnet handy, and move the stir bar up the side and fix it with the magnet while you pour the contents out.
 
One thing I did wonder is how you stop the stir bar accidentally falling into the wort. But you'd just keep an extra magnet handy, and move the stir bar up the side and fix it with the magnet while you pour the contents out.

I just use a magnet to pull the stir bar up and out of the flask before decanting or pitching.
 
I'd not thought about that! That sounds perfect, if it wasn't for that fact that I only have an electric hob...


I've just bought myself a 2l conical flask for making a starter. I'd thought a stirplate would be overkill for my setup, but I'm looking into overbuilding my starters to cut down my yeast costs, and some test calculations suggest that flask would be getting a bit full with just shaking, so I'm going to order the parts for this and give it a go. Thanks for posting the guide here.

One thing I did wonder is how you stop the stir bar accidentally falling into the wort. But you'd just keep an extra magnet handy, and move the stir bar up the side and fix it with the magnet while you pour the contents out.
I use a flask on an electric hob, it's ok as long as it isn't one of the exposed element types.
I built my stir plate for the exact same reason, I began over building starters and it's a great way to get a few uses out of a yeast vial.
Yep a spare magnet to hold the stir bar in place when pouring.
 
I use a flask on an electric hob, it's ok as long as it isn't one of the exposed element types.

Thanks, mine has a solid circular plate, rather than the coiled element being visible. I might put it on a heavy bottomed frying pan, just to be on the safe side.

Do you submerge it into cold water straight after boiling too? Or let it cool a bit by itself first? I've had a quick look at the properties of Borosilicate, but I'm still paranoid about things like this! (Obviously nobody's going to give any guarantees, that's the nature of things like this).
 

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