The Inner Driven gear drives have the capability to mount two motors onto a single gear drive.

I thought mounting two of my Permax 450 Turbo motors would make an interesting power system. These hybrid "400" size motors have the power of a Speed 600 motor and they are lighter than a Magnetic Mayhem or Endoplasma.

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The gear drives use a standard R/C car 48P pinion gear which are both inexpensive and readily available. Name brands like Robinson Racing Products or Bolink can be found at your local hobby shop.

I used 19T pinion gears for a 3.9:1 ratio.

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Hi Greg. I've got a Mini Demon on loan, and it sure does seem beefy for this class of gearbox. At 3.1 oz, it's a bit on the heavy side, though that does include the integrated motor mount. At this weight, it's probably best suited for dual motors, but seems overkill for a single. I'd sure love to see a third post for mounting, as it would provide much better stress distribution than two.

I think the Inner (and Mini) Demons have great potential with some refinement, such as a third mount post and a slight diet. Given that, they could take eflight by storm.

I have yet to put one to use, so keep us posted on your results.

BTW, could you point me to a source of 450T replacement brushes?


- chris

Hi Chris,

Since the wind is blowing again this weekend I decided to find a "housing" for my Mini Demon setup.

The closest thing I could find was an old decommissioned Hacker Helio Courier. I used it as my first ground trainer for practicing takeoffs and landings in our parking lot at work. It has had tremendous abuse during that learning period.

The gearbox and motors simply screwed into the firewall. I was impressed with those sinking, self-locking nuts!

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I had been using a Velcom 24/10 with an APC 8x4 glow prop on 7-cells of CP2400. The setup would draw about 30amps. It had marginal power for this heavy 50" span model so you needed to keep the nose down and fly it instead of powering it though takeoffs.

The largest prop this model will handle is a 12" prop so I put on an APC 12x8 e-prop. On 10-cells, it draws about 16amps.

This is about 1/2 the maximum current that I can draw on this setup so it appears that I can probably spin a much larger prop.

The 16amp (8amps each) draw will make the Turbo 450 motors very happy so they will probably last forever. It also allows me to use a very light 10-cell 1100mAh HE cell pack at 7.3oz. When compared to my original 7-cell CP2400 pack at 15.3oz, my weight reduction is 8oz or 1/2 lb!

About 1/2 of that savings is lost in the weight difference between my complete Velcom 24/10 setup (motor, mount, prop, & adaptor) at 10oz compared to my Mini Demon dual 450 setup (with prop) at 14oz.

I'll probably still give it a test drive since I don't care if I totally destroy my Helio Courier. I may also get a 12 or 14 cell HE cell pack.

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