# Vent Motor on Batteries?



## drzeus (Jun 25, 2011)

Has anyone tried this?
I ran a very small prop (basically no load at all) via a vent motor powered by 6 "c" cells. Its still turning after 8 hours.
Has anyone tried this under a real prop load?
And how long did your batteries last?

Ive made a coupla life sizes that are currently powered by walwarts, but I'm thinking that batteries would be a lot more convenient.
One of my prop is a pvc frame whose head turns side to side, and the other, a witch stirring cauldron.

Thanks for any input...

DrZeus


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## Screaming Demons (Jul 12, 2009)

I know someone who used a 9-volt battery for a while with a load and he said it worked OK. Using rechargeables would be the way to go.


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## coolbotz (Oct 21, 2009)

Run the vent motors on RC car 7.2V or 9.6V batteries and they last for 20+ hours. Also make great counter weights.


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## drzeus (Jun 25, 2011)

Thanx guys for the suggestions.
The damn thing is still turning 21 hours later...
Going to work. We'll see if its still going 9 hours from now.!


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## drzeus (Jun 25, 2011)

29 hours...
Still ticking...


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## austenandrews (Aug 22, 2010)

I ran them (with light load) on two D batteries (converted cheap flashlights into battery cases). They were still going strong the next morning.


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## drzeus (Jun 25, 2011)

Took the battery holder off of the original prop (very little load) after about 50 hours continuous run-time.

Using the same batteries (I'm a cheap freak), I connected it to my grave popper (Serious Load)- Its been running now for 2 hours. The upload swing of the load is pretty slow (I get about 3 rpms overall (which is about what it was getting originally- I believe)). I assume this is due to to decreased voltage (12volt-> 9volt). Torque seems reduced compared to walwart also.
Batteries do not get warm.

Will a upgrade to 8 "C" cells bring my rpms back to 6ish with more torque?


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## austenandrews (Aug 22, 2010)

They're 4 rpm motors at 12V. The rpm and torque both decrease with voltage, which is why 9V gave you 3 rpm. If you want the same torque and lower speed, you have to do more than lower the voltage.


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## drzeus (Jun 25, 2011)

Thanx Austen.
For some reason I thought they were rated at 6rpm.

And if anyone is interested, the full load prop ran for another 50 hours (after running 50+ hours- no load) on the same batteries! I was shocked.

It is still turning after 100 hours total.
I will report back when the damn thing finally dies...


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