zoom
Elite Veteran
Location: Galveston, Texas
| http://www.rotorworks.net/viewtopic.php?t=708
I was hard pressed to find a wide variety of 2.3mm pinions, I came up the a idea of how your can use a small peice of brass 1/8" brass tubing to convert your 2.3mm shaft into a 1/8" shaft. You will need some loctite and the brass tubing with can be found at a local hardware store, or Hobby-lobby.com for $0.99 cents plus $8 shipping (sucks) so, get it at the hardware store for $1, and call it a day .
Once all done you can, purchase those 1/8th or 3.2mm bore pinions which are very abundant and sold everywhere, or you can find them at tower hobbies.com
In the pic below, you will see that I have inserted a black 2.27mm drill bit (near the red pen on the right of the pic) into the brass tubing to simulate the motor's shaft for you all. It slides in easily, but not too lose to where you have to worry much about too much runout or lack of trueness. I'm ordering my 1/8" steel pinions and I will let you all know how it goes.
Why is this significant?
Answer: This is significant because now you can have more versitility with with all of your motors. You can now use lower kv airplane type motors on your heli. The only obstacle was find larger tooth pinions. The lower the kv, the higher the tooth was needed in order to acheive a decent heli headspeeds.
How did the idea come about?
Ans: The idea came about when I purchased a MTM 400F (2250 kv) BL motor for my foam Jet, and since it was a 15-16 amp motor capable of delivering 180 watts while only weighing 43g, I decided to try it in my hummer. The problem was pinions for a 2.3mm shaft larger than 13T were hard to find. So I got some 99 cent 1/8" OD brass tubing and convert the motor's shaft to a 3.2mm or 1/8" in order to have a large variety of options available regarding pinions.
Now I have 21T pinion on my shaft and will be able to generate headspeeds >3000rpm if I choose. Prior to this conversion, I had a 2.3mm bore,15T pinion that only gave me a headspeed of 2250rpm.
Here is a video of the conversion:
http://www.runryder.com/helicopter/...aft_convert.zip
Finished Video:
http://www.runryder.com/helicopter/...ing_3150rpm.zip
Tools:
$0.99 K&S 1/8" brass tubing
$ 3.00 Micro Tubing cutter from Home Depot
and locktite
as I always I try come up with dirt cheap solutions. I hope you all can benefit. |
