Servo Weight - 6.6g vs 7.8g - when does it matter?
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Servo Weight - 6.6g vs 7.8g - when does it matter?
When looking at servos, when would you buy a 6.6g 8.33 oz-in servo and at what plane size would you look to buy a 7.8g 20.8 oz-in servo in the same role? The 6.6g servo being $1 more than the 7.8g.
Seems like you could use the 7.8g servo for more stuff.
somegeek
Seems like you could use the 7.8g servo for more stuff.
somegeek
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RE: Servo Weight - 6.6g vs 7.8g - when does it matter?
For this small an amount I would certainly suggest the larger, cheaper and more powerful servos that will also likely be a lot less fragile to vibration and crash damage. Even with 4 servos in a model you're only looking at an extra 4.8 grams or 1/4 oz. That much of a tradeoff for what SHOULD be a more dependable servo is worth it.
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RE: Servo Weight - 6.6g vs 7.8g - when does it matter?
I sometimes look at some of these servos as false economy. When very small, you have to slow them down to get the torque up. But regardless of the advertised torque, gear tooth mass on these tiny servos is so small that stripping a gear is a real possibility. Years ago, radio reliability was the weak link in flying. Radios are pretty solid now, so servos have moved to the top of my "suspect list". If you stick a plane today, aside from dumb thumbing, it's probably going to be servo failure. I would rather give up a little weight for a little more peace of mind.
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RE: Servo Weight - 6.6g vs 7.8g - when does it matter?
As the wise posts above, I would go for the slightly higher weight over the smaller servo. As pointed out above, a overload on the servo may cause it to fail, or be more prone to crash damage with the smaller gears.
I have used the Futaba 3114, and the 3110 (that one is no longer being made by them), both sets still work great. The higher torque is for peice of mind, I have had less torque servos stall out in flight, but it may have been from drag on the hinges. I also have had failures on cheaper, non brand name types, but not with the Futaba stuff.
Just my 2.5 cents.
I have used the Futaba 3114, and the 3110 (that one is no longer being made by them), both sets still work great. The higher torque is for peice of mind, I have had less torque servos stall out in flight, but it may have been from drag on the hinges. I also have had failures on cheaper, non brand name types, but not with the Futaba stuff.
Just my 2.5 cents.