could you do some side by side test that are less subjective then flying your plane?
I woould like to see a clip where you show the speed and centering under load compaured to other servo's

Could I suggest that before writing reviews like this you at least take the trouble to find out the correct units for torque? AFAIK there's no such thing as an in./oz - certainly not for measuring torque. Makes it very difficult to know what you're talking about.

David

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look a bit closer yourself. The link you give is correct, and it does NOT list ounce/inch.

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Nice article,id really appreciate some video also,maybe showing the same plane with the original servos vs the new brushless futabas during a preflight to show how smooth or fast they are as well as seeing flights with both servos,the test flight sounded cool.. It would rock to see it. Just an average rc pilot here but never heard of planes doing a tick tock just helis ?. You can compromise on servos but they can make a huge differance in flight performance.. both in crispness and response,torque and speed sound VERY good on these and they should fit many applications very well that call for full size servos .

you do indeed see ounce inch - that is ounces multiplied by inches NOT ounce/inch - ounces divided by inches.

If you measure a force of 4oz a distance 2 inches out from the shaft that is a torque of 4oz * 2inches = 8 oz.inch.

It is not 4oz / 2 inches = 2 ounce/inch.

It's a HUGE difference as in one makes sense and the other is complete rubbish.

As an example which should have the '/', if you travel 60 miles in 2 hours, then you are travelling at 60 miles / 2 hours = 30miles/hour.

As a result, if you travel for 10 hours, you can expect to travel 30 miles / hour * 10 hour = 300 miles.

By the same token, if a servo really produced 100 oz/in, then at a distance of 10 inches, you'd expect to get a force of 100 oz/inch * 10 inch = 1000oz

If it's 100 oz.in, then at the same 10 inches you'd expect 100 oz.inch / 10 inch = 10oz, which I think most people would agree is more likely.

David

Nice review Ian. Could you post a picture of the new grommet all by itself? It's a little hard to see the inside detail in the installed shots. How expensive is this servo?
Mike McD

Originally Posted by daleksw

Could I suggest that before writing reviews like this you at least take the trouble to find out the correct units for torque? AFAIK there's no such thing as an in./oz - certainly not for measuring torque. Makes it very difficult to know what you're talking about.

David

Even I know what he's talking about. But why some cultures cling on to these old imperial units of measurement is beyond me. Whats wrong with the metric system?

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Originally Posted by mop26921

I understand now. Thanks for the explanation, I have learned something.

Well I'll assume you got the figures off the packaging then and didn't actually measure them.

Could you tell me where these servos are made. At a guess I'd say China and that would explain the inch/oz typo on the box? Or was that your mistake.

Originally Posted by electron_head

Even I know what he's talking about. But why some cultures cling on to these old imperial units of measurement is beyond me. Whats wrong with the metric system?

Honest, it's not a question of imperial vs metric units. oz.in is a measure of torque. oz/in isn't and neither is in/oz.

Apologies to mop26921 if I seemed to be getting at you, that's not what I had in mind at all. I happen to think that anyone who's going to present a review and give the impression of being in some sort of position of authority on the subject ought at least to know what they're talking about. The reader's don't have to understand every word, but the writer should - otherwise don't write it.

I can happily cope with torques in oz.in, kg.cm or preferably N.m. I can even cope with kg.m^2/s^2 or dimensionally equivalent units of energy like Joules, calories, electron Volts or even the incredibly obscure horsepower.fortnight and dyne.cubit - obscure as in I just invented them. But to repeat myself, oz/in and in/oz are not measure of torque or anything else I can think of.

If I told you I weigh just over 75 Fahrenheit, would you be able to tell me if you were lighter?

David

Originally Posted by daleksw

If I told you I weigh just over 75 Fahrenheit, would you be able to tell me if you were lighter?

David

Getting pedantic now. You have quoted the speed as being:

Speed: 4.8V: .13 sec, 6V .10 sec

I know that this is actually the time to rotate thru 60 degrees but ...

These servos could actually go over 100mph in the right plane.

And for your information I weight about 68. Over on the US they would say I weigh about 150 and everyone would know it was pounds.
2.2 pounds to the KG.

68 KG is 68 000 grams but whats 152 pounds in onces? Its takes a bit longer to fiqure that one out and time is money.

You still haven't told me where the servos are made.

http://www.futaba-rc.com/servos/futm0550.html

Blah, blah, blah... and the beat goes on.