Last year I had switched from batch sparging to fly sparging, and in the process had built a simple rotating sparge arm. It worked how all rotating sparge arms work. The water exiting the drilled holes had enough force to spin the sparge arm. The only problem with this design was that my flow rate was FAR too high to properly fly sparge while still having enough flow rate to rotate the arms. So, the end result was a rotating sparge arm for the first minute while I got an inch or so of water on top of the grain bed. Then I would slow it down to a trickle and the arms would stop spinning. This way works just fine, but it doesn't have that satisfaction that comes with watching your sparge arm spin...
So that's what made me decide to put together a simple electric rotating sparge arm. The premise is simple. A small 1.5-3 volt electric motor spins the sparge arm independent of water flow. This way I can set the flow rate to whatever I'd like, and then I set the speed of the motor to whatever I'd like. This way I can have my cake and eat it too!
The sparge arm is made with 1/4" PEX tubing with SharkBite fittings.
The electric rotation design is simple (and obviously not designed with aesthetics in mind!). The motor has a small gear on the end, which spins a gear on the rotating portion of the sparge arm. The motor is angled slightly so the gear teeth can engage, since the gear on the motor is too small to engage the teeth of the other gear. I did this by balling up a piece of electric tape and putting it behind the motor. Then I took a thick rubber band to attach the motor to the non-rotating portion of the sparge arm.
With the motor hooked up directly to a battery, it spun too fast, and the water just flung onto the sides. So, I added a potentiometer between the battery connection and the switch so that I can control the speed of the sparge arm.
Here's a video of it in action:
[ame]https://www.youtube.com/watch?v=y_zsEb7IIyM[/ame]
If I remember correctly, the basic rotating sparge arm cost me about $15-20 or so. The upgrade cost me about the same.
Most parts I sourced from my local Radio Shack.
-motor - $3
-potentiometer - $3
-potentiometer knob - $3.50
-switch - $4
The gear I found at a local hobby shop for $4. I already had the wiring.
I could have easily saved a few bucks by shopping online, but it still only cost under $20.
And I completely realize a rotating sparge arm is unnecessary... but half the fun of homebrewing is building your own stuff!
So no need to waste everybody's time pointing this out.
So that's what made me decide to put together a simple electric rotating sparge arm. The premise is simple. A small 1.5-3 volt electric motor spins the sparge arm independent of water flow. This way I can set the flow rate to whatever I'd like, and then I set the speed of the motor to whatever I'd like. This way I can have my cake and eat it too!
The sparge arm is made with 1/4" PEX tubing with SharkBite fittings.
The electric rotation design is simple (and obviously not designed with aesthetics in mind!). The motor has a small gear on the end, which spins a gear on the rotating portion of the sparge arm. The motor is angled slightly so the gear teeth can engage, since the gear on the motor is too small to engage the teeth of the other gear. I did this by balling up a piece of electric tape and putting it behind the motor. Then I took a thick rubber band to attach the motor to the non-rotating portion of the sparge arm.
With the motor hooked up directly to a battery, it spun too fast, and the water just flung onto the sides. So, I added a potentiometer between the battery connection and the switch so that I can control the speed of the sparge arm.
Here's a video of it in action:
[ame]https://www.youtube.com/watch?v=y_zsEb7IIyM[/ame]
If I remember correctly, the basic rotating sparge arm cost me about $15-20 or so. The upgrade cost me about the same.
Most parts I sourced from my local Radio Shack.
-motor - $3
-potentiometer - $3
-potentiometer knob - $3.50
-switch - $4
The gear I found at a local hobby shop for $4. I already had the wiring.
I could have easily saved a few bucks by shopping online, but it still only cost under $20.
And I completely realize a rotating sparge arm is unnecessary... but half the fun of homebrewing is building your own stuff!
So no need to waste everybody's time pointing this out.
