View Full Version : Looking for 9t pinion for Trex 600e
heirmeistr
04-22-2008, 04:05 PM
Anyone have an idea where I can get a 9 tooth pinion for a Trex 600 electric?
Needs to fit a 5mm shaft and have a 0.7 module. I want to slow down the headspeed but keep up the motor RPM. Thanks
sgil123
04-22-2008, 08:48 PM
Harry
Which motor are you running on your 600 is it the 600L or the 600XL1750kv? Also what is the smallest pinion you have? What is the head speed you are trying to achive?
heirmeistr
04-23-2008, 01:32 AM
I am using the 600XL 1650kv motor. I still have the 600L 1620kv motor on a shelf. The smallest pinion I have is a 10T. By my calculations, using the 1650kv motor, 22.2v (6s LiPo) battery, 10t pinion, 170t main gear, and assuming a 90% efficiency, I would get over 1900 rpm. I am being told the max scale rpm I want is 1600 with the acceptable range being 1400-1600. So if I can get my hands on a 9t pinion, I figure my rpm would be slightly over 1700 which is getting it in the acceptable range.
sgil123
04-23-2008, 08:16 AM
Try going to the 188 helical gear with the 10t (I've not seen a 9 tooth pinion) using the 600L motor this will get you to 1720 rpm for the head. You may want to go to the 100-120 amp ESC if your going to run more than 2 blade head.The only problem that I see from here is you may loose tail authority with lower head speed. Are you going to use the 620mm blades? Mavrikk makes a set also. Let me know how this works out
heirmeistr
04-23-2008, 03:13 PM
Oh my G! Why didn't I think if that. The 188T main gear will do exactly what I was looking for. I was so fixated on the pinion gear I didn't even think of the other half of the equation. I already updated the Align 75 amp ESC to the 100 amp ESC. My first order of business is to get rid of vibrations. The heli seemed to fly fine at over 2,000 rpm but at 1,700 rpm there was a definite vibration. I am replacing all bearings and shafts in the head assembly first and then will balance the main blades (something I should of done before). Your comment about loosing some tail authority concerns me a little. What do you fly your scale at? Is it a lower rpm than 3D? Is it in the 1400-1600 rpm range? I probably should bump up my gyro gain with a lower headspeed, right?? I am fairly new at flying so I am very willing to listen.
Thanks
sgil123
04-23-2008, 03:18 PM
right now I'm at 2100rpm like it better when battery wears down figure HS is about 1800 settles in nice and seems to handle well but the battery doesn't last long enough to really evaluate total performance This is using the 620 SAB blades Try the gain increase gyro if the tail wags then back it off until it doesn't. I'm by no means an expert BUT I've learned many things while crashing!
heirmeistr
04-23-2008, 06:32 PM
Well I guess I got a little too excited too quickly. Right now I have a 10T pinion and a 170T main gear. The 188T main gear is helical and the lowest helical pinion available is a 11T. Either combinaton will provide almost the same exact headspeed.
sgil123
04-23-2008, 11:03 PM
Harry take a look at this http://www.gravesrc.com/THUNDER_TIGER_MOTOR_PINION_9T_E550_E620_p/ttrpv0545.htm
It says it is for the thunder tiger 550 650 not sure if it is 5 mm shaft diameter worth a look
And another one from ready heli http://www.readyheli.com/SearchResults.asp use the search for the website type in pinion page down to page 5 towards the bottom 8 tooth and a 9 tooth
Sorry Steve but these TT pinions are 1.0 mod and you need a 0.7 mod for the Trex600 maingear. The smallest 5mm 0.7 mod pinion you can get is 10t. If you want lower HS you will need to go to a lower KV motor.
Cheers,
Tom C