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Old 12-07-2011, 05:32 AM   #1 (permalink)
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Join Date: May 2010
Location: Ankara, Turkey
Default My homemade onboard generator mount for Helibug Trex 700 gasser

I wanted to mount the brushless motor to the start shaft because the motor in tail TT gear shaft doesn't look safe to me.

I tried the stock clutch One way bearing (OWB). No success because an OWB needs load to lock its shaft. The brushless motor can not provide such load. Therefore OWB stops holding the shaft over 7-8 k RPM. So the motor stops rotating. Battery drains, heli crashes. I have tried a few different OWB's. One of them is a BOCA high speed OWB (19k) but it still needs load to work at 13k RPM.

I find a good balanced (some of them are not balanced) 12mm hex wrench bit and 12mm T60-61 hex shaped aluminium rod. OD of the bit is +-0.05 18mm. I machined the alu rod until i get 5mm thickness. The root remains 12mm hex. I replaced the wrench bit with the OWB in the clutch. Replaced the machined alu part with the stock clutch start shaft.

You can name this as a winter project or an experiment. Either way this setup works good for now.

Edit:I'll add more photos for the rest.
Trex 700 Gasser
FBL | HeliBug HB7-RC 17T | Silverline V-Bar| TRM VX290TT | SG | RJX Gas muffler (modded)
Trex 600 Gasser FBL | HeliXHeli conv. | OS GT15HZ | iKon | Homemade onboard generator
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