Torque of motors

[venture]

Seems like every single motor made now is either "high torque" or "high speed" in designation. Oddly enough, no one seems to make a "normal torque" or "normal speed" motor. Not inspiring enough I guess.

Well, I am interested in building a chart to compare torque @ rpm for different motors available for airsoft use.

My problem is lack of training in this field. I believe that attaching the motor to a spindle and winding a string attached to a weighted lever until stall could measure relative torque @ 0 rpm. I would prefer to be able to measure torque @ any rpm.

Is this possible at a reasonable expense? Any doctors have the training to build a dynamometer for our small motors?

[HKGhost]

you might want to look into RC dyno. You will have to modify it to hold our AS motors and a way to connect the shaft to the dyno.

[Shell Shock]

i too, would like to see this done. *subscribed*

[flack]

Mouse based dyno



Maybe you will find this interesting

http://www.sci-spot.com/Mechanical/dyno.htm

(you can buy a kit on the site)

[archer1276]

Originally Posted by venture

Seems like every single motor made now is either "high torque" or "high speed" in designation. Oddly enough, no one seems to make a "normal torque" or "normal speed" motor. Not inspiring enough I guess.

Well, I am interested in building a chart to compare torque @ rpm for different motors available for airsoft use.

My problem is lack of training in this field. I believe that attaching the motor to a spindle and winding a string attached to a weighted lever until stall could measure relative torque @ 0 rpm. I would prefer to be able to measure torque @ any rpm.

Is this possible at a reasonable expense? Any doctors have the training to build a dynamometer for our small motors?

Thank God! Seriously, I have been wondering why manufacturers and dealers dont list this info. While ounce-inches and pound-feet may not mean much to the layperson, numbers DO. I used to work on R/C cars growing up and the big marketing thing for these electric motors in the 90s was to call them single, double,triple, quadruple or quintuple-wind motors, referring (I believe) to how many times the wires were wound around the rotor magnets.

Now if you were to go on evike.com or airsoftgi.com, they simply list motors in the manner you described above! And every manufacturer has their own brand which they claim is awesome, but it never gives exact specs and certainly not numerical values. High torque, high speed or some new-fangled motor which claims to do both, are all I can find. There must be a simple physics model that can help help calculate motor rpm and torque with and without load.

Thoughts?

[CJay]

I can tell ya that most of the distributers of these fine hand made quality... Chinese made parts don't have a damned clue either lol. So
Much rebranding goes on that ull be lucky to get a straight answer. For example 007 torque up motors are just Guarder infinite torque motors. Not rebranded but made in the same assembly line and have a different sticker slapped on. I think u will also find that with most all manufacturers that the specs vary so wildly that general Specs on a motor are useless or at least wildly inaccurate for the vast majority of the motors out there.

[krap101]

With regulation come fees and more increases in cost.. Not sure if I'm willing.. Oh and more fees and more regulation...

[Kos-Mos]

Interesting idea...

But useless.

RC motors that are "Dyno spec" vary greatly from batch to batch.

For example, a RC 540 27T "stock spec" motor will run between 37k and 40k rpm, no-load at 5v.

The car you put it in will run on 7.4v LiPo (so about 10v nominal when fully charged), and the load will vary from gearing settings.


At the very least, having magnet type (ferrous vs Neodym vs ceramic), motor winding (number of turns on the armature) and configuration (dual/quad magnet, single, double, triple wind) would help.

As a baseline, I opened a TM eG1000:
Dual ferrous magnets.
Brass cast busings.
21t single armature, machine wound.

That would be an average motor.

[Cammer]

I have two RC motor dynos that I would love to use again. One is an inertia dyno which will give some indication of power but the other is a torque based dyno will give very solid numbers. If anyone wants their motors checked I would be happy to do it for free if you send them with return postage. Send me a pm and let me know what voltage you are using as they will vary on powerband depending on volts used.