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Old 06-30-2005, 11:33 PM   #16
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bwhahahahaha wat af unny story...

atleast you can admit your own mistake...

wierd how the rear broke off
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Old 07-01-2005, 01:30 AM   #17
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Quote:
Originally Posted by ntc3freak
i was not talking about the linkage.the spring i was talking about is a spring attached to the carb so it can close the carb when the rx pack fails.understand???

But even then, this will NOT always work.....
Not al servo's You can turn back with a spring.....
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Old 07-01-2005, 01:58 AM   #18
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Sorry about what happened, but I give it to you, you described the incident VERY entertaining



Quote:
Originally Posted by espo16
well here goes.
bought a sirio tup af 5 porter.
unintentionally cut the d**m crankshaft too short. tried to order it for two weeks no one in the damn states had it. finally found one in singapore. took three weeks to get it. finally got here, cut the crank the right length this time and started breaking her in. 7th tank she was looking good. started leaning her out. ssssmokinnnn!!!!!! i noticed that my rx pack was really weak. so instead of doing what any other "normal" person would do, STOP AND CHARGE THE PACK, my dumb ass went to the toolbox, grabbed the stock AA pack and put the smallest, flimsy ass zip tie i could find and tied it to my shock tower. what a damn idiot!!! 8th tank hit a bump, battery pack came loose, wire went under tire, came unplugged, you know the rest of the story. full throttle, up a small 2 ft hill (grass), BOOOOOOOOOM!!!!!!!!!!!!! into the fence. i was about 150 yards away so i had to run the fastest damn 150 yards in my life. so fast i could have beaten maurice williams AND justin gatlin. engine ran full throttle for about 15-20 seconds. thank the lord almighty i was running it richer than oprah winfrey. here's the aftermath.








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Old 07-01-2005, 06:32 AM   #19
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Quote:
Originally Posted by stefan
Sorry about what happened, but I give it to you, you described the incident VERY entertaining
I agree, I feel bad for you, but I was cracking up as I read your description. Good luck with the repairs. And the Car too
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Old 07-01-2005, 06:48 AM   #20
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i have a 2173 on mine and it is hard to turn. no spring would turn it. i can't tell what kind is on yours, but i would imagine the same thing went on.
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Old 07-01-2005, 07:32 AM   #21
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Quote:
Originally Posted by M7H
But even then, this will NOT always work.....
Not al servo's You can turn back with a spring.....




true also.but i think he was using rtr servos which is not that powerful.i think a throttle spring will help if used with a weak servo.......no???
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Old 07-01-2005, 07:34 AM   #22
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Quote:
Originally Posted by espo16
i quit. you won



don't worry.the damage was not that bad man.probaly only 20-30 usd should fix that.that is a cheap return if u ask me.could have been a lot worse.i mean ALOT worse
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Old 07-01-2005, 08:06 AM   #23
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Quote:
Originally Posted by ntc3freak
true also.but i think he was using rtr servos which is not that powerful.i think a throttle spring will help if used with a weak servo.......no???
No, even a weak "cheap" servo might be to "strong" for a spring to pull back......
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Old 07-01-2005, 11:47 AM   #24
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Guys, a throtle return spring doen't need to pull back the servo arm while sitting on your work bench. What happens is when your engine is running, the vibrations cause the spring to gradually return the carb to the closed position. To strong of a spring will kill the servo and make your receiver batteries run down too fast.
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Old 07-01-2005, 01:00 PM   #25
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I don't know who is right and wrong now....but here is what throttle return spring will work, only if you do have.....

(1) Usually, a HIGH END servo, not the RTR one, not the $30 one, I would say something like $65 and above high end digital or analog servo, that has nothing to do with the speed and torque of the high end servo, that has to do with the internal gearing of the servo. High end servo, you can turn it left and right without effort, low-end, or RTR servo, you have to turn it with a lot of force....no throttle return springs can do that, only if you ahve a high end servo.

(2) Again, after you purchased high end servo, your throttle return spring(s) should not, and will not damage the servo, nor causing the carb to close while vibration...........because, those HIGH END servo, when powered on, should generate at least 90 oz of torque easily (alot of them can be above 120 oz).............no throttle return springs can pull back the servo that can generate with all those power..............UNLESS, the servo has no power (exactly the same thing happened in this case, no power WOT runaway)...when the high end servo power is off, the gearing is very easy to turn around.......then the throttle return spring will be able to pull back the carb to close, or even pull the servo to BRAKE position...

Overeall, if you are running fail safe, you are OK ONLY if your batteries pack is still plug in, the computer will PULL to the brake position by using the last several % of power in order to tell you to pick up your car....but in this case, only a set of throttle return spring with a high end throttle servo could able to save his car....may not be a complete stop, but at least closed the carb and the car should be sliding down slowly....

Last, don't even bother to mount a throttle return spring on a RTR servo, it won't work...
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Old 07-01-2005, 01:15 PM   #26
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Well I just put a Airtronics High Torque (94358) on my MTX3 and I haven't been able to find a spring that will pull it back. Has anyone had any luck with that one?
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Old 07-01-2005, 01:48 PM   #27
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Quote:
Originally Posted by gonzoY5
Well I just put a Airtronics High Torque (94358) on my MTX3 and I haven't been able to find a spring that will pull it back. Has anyone had any luck with that one?
200 oz/inch.........talk about POWER....
Anyhow, I had use the Team LOSI throttle return spring kits, came with 2 springs, mount both of them....then, mount the other end to the distance that does PULL the servo back to teh close or brake position.......sometime, it need the extra inches.......

I don't use them anymore cause I think futaba build in fail safe does the work already.........even the OFNA $20 add on fail safe does work pretty good on my 835 after I daredevil it on a 60 mph WOT and turn off my radio in purpose stunt...(yes, I was STUPID...)

I think 200oz/in for throttle is way over kill, that servo is MORE then enough to be a steering servo for 1/8th scale.......I think it will better fit to use it for steering then throttle.........a little bit easier for the throttle return springs to pull as well........
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Old 07-01-2005, 02:17 PM   #28
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Quote:
Originally Posted by Rookie Solara
I don't know who is right and wrong now....but here is what throttle return spring will work, only if you do have.....

(1) Usually, a HIGH END servo, not the RTR one, not the $30 one, I would say something like $65 and above high end digital or analog servo, that has nothing to do with the speed and torque of the high end servo, that has to do with the internal gearing of the servo. High end servo, you can turn it left and right without effort, low-end, or RTR servo, you have to turn it with a lot of force....no throttle return springs can do that, only if you ahve a high end servo.

(2) Again, after you purchased high end servo, your throttle return spring(s) should not, and will not damage the servo, nor causing the carb to close while vibration...........because, those HIGH END servo, when powered on, should generate at least 90 oz of torque easily (alot of them can be above 120 oz).............no throttle return springs can pull back the servo that can generate with all those power..............UNLESS, the servo has no power (exactly the same thing happened in this case, no power WOT runaway)...when the high end servo power is off, the gearing is very easy to turn around.......then the throttle return spring will be able to pull back the carb to close, or even pull the servo to BRAKE position...

Overeall, if you are running fail safe, you are OK ONLY if your batteries pack is still plug in, the computer will PULL to the brake position by using the last several % of power in order to tell you to pick up your car....but in this case, only a set of throttle return spring with a high end throttle servo could able to save his car....may not be a complete stop, but at least closed the carb and the car should be sliding down slowly....

Last, don't even bother to mount a throttle return spring on a RTR servo, it won't work...

agree, I'm not sure what servo's people are using but all my digital 6v ko-propo servos are so easy to rotate when the power is off and it is not fighting against the opposing force.

currently I'm trying out a hitec HS-5625MG digital servo (which aint all that expensive), and fitted a spring with about the right rate I thought would return the carb if power is lost. the servo produces just over 100oz/in of torque and has no problem pulling the spring back and the spring has no problems pulling the servo bk if power is lost. The effort needed to apply the breaks will greatly outway the force needed to overcome the spring.
I suggest you try a different servo or experiment with different spring rates to get the perfect balance. A fail safe circuit alone wouldnt of helped this guy maybe both a spring and fail safe setup is the way forward if you want to be mega careful.

cheers
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Old 07-01-2005, 02:38 PM   #29
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i do not think it is the torgue of the servo that will cause the spring not to be strong enough to make it return. i think it is more of how the gears are geared down, if they are lubricated, the tightness of their mesh, and if they are all steal. i think the combined factor of these elements will determine if the servo will be too tight to come back. the bottow line is all servos are motors with gears attached. how well the gears are disigned and maintained will give you the smoothness of the servo.
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Old 07-01-2005, 02:53 PM   #30
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I run a failsafe and a return spring. I've never been able to get a return spring to pull the servo back. I've heard they will on digital servos though. I use the return spring just incase the linkage pops off the throttle arm.

The best lessons learned are usually the hard way!!
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