Uncas

My Feedback: (1)

I have just changed to digital to get better repeatability on my idle.

cap10b

Hamman,
Something scary happened the other day at our field, a friend flys a comp ARF 300 and he has analog Hitech 615 or 605 can't remember, he was flying and all of a sudden said I got no throttle lucky for him he had low to barely above low left and when he landed we sort of had to chase the plane down to get it to stop (lucky for us we have a raised runway and the hill stoped the plane) Checking out the servo situation the servo motor was burned up or the board or the Reostat or something. Well that got me to thinking I sure am glad I have a choke servo on my 3W if anything happened I could hit the choke and kill the motor.

jds

ICE 32 ICEMAN

My Feedback: (1)

Cap 10B,
I have tried servos to do engine-kill functions and also have used high dollar fiber optic kill setups. I currently use a fast 8417 JR digital for my throttle and I liked your idea of using a servo to operate the choke arm on a gasser. I guess choking an engine to death is as good as killing it electronically. What happens to all that fuel in the cylinder the next time you flip start it? Any chance of getting the crap knocked out of your hand when flipping it to start? Just curious. Sounds like a good idea, though........
Terry

cap10b

Iceman,
I wondered that very same thing and after killing the motor that way several times all that happens is you dont have to choke as much on restart infact you dont have to choke at all. My 3W-75I after starting for the first time of the day doesnt need to be choked again unless it sits for several hours between flights. If I land and the plane sits for 10-20 minutes and then I go back up I turn the ignition on and pow! she starts up first flip usually. The only time I have seen kick back on the new IIS 3W ignition is when you have a major leak like a cracked reed block or warped carb surface and those usually come from over heating the engine.
A friend had a 3W-106 CS competition motor he ran in a comp arf and we got to messing around with the motor and somehow we cracked the reed block and the motor wouldnt start and we flippled and flipped and the all of a sudden KA-POW that motor kicked the holly crap out of the owner kicked me too. Needless to say the motor was boxed up and shipped in for repair.
Also I shy away from digital on throttle and choke, I am a big QQ Aircraft fan and QQ says digitals fail hard over most of the time and I believe that I had hitec digitals fail hard over and a friend just had a JR 8611A fail hard over. So I use analog on throttle and choke. A fast coreless analog in the 90 in/oz range speed about .09 to .07 . As far as nylon versus metal I use nylon and do not unhook the carb spring, if the gears strip the carb will close by its self another QQ trick.

Works for me anyway.

Johnny

Jaffray

My Feedback: (5)

I have wasted several of those little blue servos controlling the throttles of the three MVVS 26's on a VTOL UAV prototype. It was not the gears that quit, but the circuitry. The HS 81's do just fine, however, and the torque required to run any throttle should not be more than 20 oz. Vibration is the enemy of the throttle servo. Metal gears should not be used in any instance, as they will quickly wear to the point of generating RF noise. Arranging the linkage to utilise the full travel of the servo will help to extend the life of the servo, and provide better resoloution at the stick.

captinjohn

For a kill switch...how would a servo set up to unplug a deans connector. If you ignition power source is unplugged....the engine will stop!! Just secure one end of deans connector and have the plug in part hooked by #90 test fishing line to servo. Capt,n