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Old 12-03-2014, 02:01 PM   #61
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Originally Posted by Slapmaster6000 View Post
Howard, just for show, I tested a motor every 5* starting at 25* just to see where the amps went nuts.

25* @ 0.9a
30* @ 1.2a
35* @ 1.4a
40* @ 1.8a
45* @ 2.3a
50* @ 5.5a
That is what I have seen on the Fantom Dyno also. Once you get passed 45 deg. The rpm will jump with the amp draw. The bottom end torque also goes away though. Something you cannot see with this device.
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Old 12-03-2014, 03:04 PM   #62
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Well, mine just showed up in the post, time to unsolder every motor I own.
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Old 12-03-2014, 05:12 PM   #63
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Well, mine just showed up in the post, time to unsolder every motor I own.
Enjoy! Make sure the screws holding the motor mount are secured tight, I had one come loose. You don't want a screw rattling around on top of the circuit board.
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Old 12-03-2014, 08:08 PM   #64
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Can you test with the motor connected to the esc or would that damage the esc?
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Old 12-04-2014, 01:05 AM   #65
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Can the Gforce be used to set timing on a motor????
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Old 12-04-2014, 09:40 AM   #66
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Can you test with the motor connected to the esc or would that damage the esc?
I do it all the time but to verify timing. I'm sure others will disagree so I'm not going to say it's safe but I've done it on all of my cars with 3.1 esc.
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Old 12-04-2014, 10:42 AM   #67
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Things I've learned:

The 40 degree mark is 62 degrees of timing on a Tekin 17.5, which means 17 amps when free spinning. I dialed it back to 45 degrees and only 3 amps free spinning amp draw on the checker. Maybe that's why that thing was such a dog.

My LRP X20 17.5 is actually advanced some 5 degrees past the claimed number on the insert, but it had one of the least variance between the three poles. Even so, it was drawing less than 2 amps at 40 degrees advance showing on the meter.

All timing is not created equal, and older motors have much less timing built into them than new ones. My old Trinity Duo 17.5 was timed at 45 degrees with the endbell cranked to the stop, but spun pretty high and only drew 2 amps on the checker. Setting my Orca RX3 to 45 degrees drew over 6 amps, and it didn't seem happy with it. The Orca RX3 seems to want less than 40 degrees.

On the other end of the spectrum, my Team Powers 17.5 only drew 6 amps with 60 degrees of advance. It seems the wind and core construction of the motor counts for more than I thought.

Modified motors get so much more out of a given amp draw. 2 amps of draw on my 4 turn gives me over 35,000 rpm.

Check your bearings. One of mine was gummed up with track detritus, and you never would have guessed by looking at it.
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Old 12-04-2014, 10:51 AM   #68
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Quote:
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Can you test with the motor connected to the esc or would that damage the esc?
Based on what I know of brushless ESC's it should be okay, but I will unsolder my motor a bunch of times for the $200 I would be risking by powering it up. The MOSFETS in ESC's are tough and hard to overdrive, but it's just not worth the risk. The only check I could recommend in good conscience with the car ESC hooked up would be checking the hall effect sensors. Just unsolder the wires to do powered tests, it's not hard or time consuming.
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Old 12-04-2014, 11:04 AM   #69
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Some great info here. Keep it coming folks! Looking forward to getting mine.
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Old 12-04-2014, 07:38 PM   #70
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Since this motor checker generates numbers under no load, is there anything we can attach to do to produce a load? Have the motor connected to a.......?
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Old 12-04-2014, 08:22 PM   #71
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the old competition electrics turbo 30's had a fan to check amp draw. you attached the fan to the drive shaft and powered it up. might try that. as long as the fan is balanced and in a shroud. i watched a guy cut himself pretty badly from a fan blade coming off while he was holding it. its a good idea but can be dangerous if not done right. maybe make a mount to hold the motor and cover the fan. dont know if it would work with this setup.
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Old 12-04-2014, 09:14 PM   #72
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Quote:
Originally Posted by dragonracing View Post
the old competition electrics turbo 30's had a fan to check amp draw. you attached the fan to the drive shaft and powered it up. might try that. as long as the fan is balanced and in a shroud. i watched a guy cut himself pretty badly from a fan blade coming off while he was holding it. its a good idea but can be dangerous if not done right. maybe make a mount to hold the motor and cover the fan. dont know if it would work with this setup.

I guess I could re-position the motor to face the opposite direction and place a fan on the end. To contain the fan from damaging me or others, I could simply get a tupperware box, cut a round hole on the side and slide the motor shaft through. Place the fan blade on, seal the top, and power it up.
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Old 12-04-2014, 09:27 PM   #73
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In the passed I have used a prop from one of my old planes to provide load.

Not as good as a brake dyno but better than no load.
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Old 12-04-2014, 09:39 PM   #74
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I guess I could re-position the motor to face the opposite direction and place a fan on the end. To contain the fan from damaging me or others, I could simply get a tupperware box, cut a round hole on the side and slide the motor shaft through. Place the fan blade on, seal the top, and power it up.
that could work. or a ducted fan housing. anything to keep the fingers protected. the guy i mentioned needed stiches. it was pretty deep.
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Old 12-05-2014, 04:16 AM   #75
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Since this motor checker generates numbers under no load, is there anything we can attach to do to produce a load? Have the motor connected to a.......?
Without a method to vary the load and measure the torque, this won't give much useful information.
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