I will try a more powerful supply. În fact I already ordered a Meanwell RS-75-12, which is rated 6 Amp.
I’m afraid I don’t have a meter that reads %PWM so the analysis you suggest will be difficult for now.
Let’s see what happens with the new PS.
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If I were you I would try a more powerful supply. If instead you have a meter that will read %PWM then you could differentiate between a power problem and trouble with the encoder pulse rate. Monitoring voltage will not be as useful as PWM because of the pulsed nature of the power to the motors.
The motors are rarely run at 100%PWM in normal use. The PID loops only ask for
enough power to move the motors at the desired speed
but if the sled isn’t keeping up with the position, the desired speed should be
100%
. Watching across the
M+/M- leads with the meter during various movements will give you a feeling
for how hard a motor is working. If you see it maxed out at 100%PWM, then more
power is the answer.
measure across the power supply, not either motor. This is not affected by PWM.
If you see the voltage at the power supply dip down from 12v, you have a problem
with the power supply not keeping up.
one way to address this is to float a 12v lead-acid (or gell cell) battery
across the power supply, power peaks will be supplies by the battery, and the
power supply will keep it charged.
but moving to a more powerful power supply is the best answer.
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The new power supply didn’t fix the problem. In fact, after a while, the motor stopped for good. It’s completely dead now. So there was probably something wrong with it from the beginning.
I’m thinking of using smaller sprockets also so that the motor s run faster and with smaller load.
Sorry to hear that that the motor quit, but it’s good to know the cause of the problem. Thanks for the update.
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Hello again,
So I received the new motor and the 10 teeth sprockets.
I installed both. Changed the setting parameter to 10 teeth.
I thought it wouldn’t be necessary to re-calibrate just re-measure the chain lengths, which i did but when I moved the sled to the center it moved to a higher position than it should (but horizontally centered).
So I decided to re-calibrate.
Now something even more strange happened: I changed the extend distance to 500 mm, I extended the chain but it seemed short so I measure and it measures about 405 mm.
I thought the new motor (left side) could be different so I extended the right one too and the same result: about 405 mm.
So whats happening here now?
I re-checked the number of teeth parameter:10
I did wipe the EEPROM before recalibrating
And I checked the groundcontrol.ini file and it had gearteeth = 10
By the way, due to the kind of problem I was having, I’m still using version 1.11.
Hello again, I’m glad to hear from you.
Are these motors the stock Maslow motors? If so, is the setting for top/bottom chain feed correct? If the motors are not stock, they probably have a different encoder, so a different setting for encoder steps per revolution. The sprockets are sized for #25 roller chain, yes?
It is possible that the previous troubles left some settings in error. Actions/Advanced/WipeEEPROM and a full recalibration is probably needed.
No, I’m afraid nothing is stock, in this case.
The thing is, everything was working fine before I changed the sprockets (13 teeth sprockets, before).
I was getting a small difference in vertical movements (less than 1 mm per 200 mm).
Motor has a different encoder (13 pulses per rev) and chain is 6 mm pitch.
The thing is, I managed to configure everything and it was working with 13 teeth sprockets. Now, if I change the sprockets to 10 teeth and reconfigure the parameter for the correct number of teeth, everything should work fine.
…but it didn’t
Wiping the EEPROM and re-doing the calibration is probably needed then. After doing that recheck the settings for chain pitch and pulses per rotation ans sprocket teeth before doing the calibration.
Keep us posted 
Something very weird happened with my motors.
I realized the motors were not turning 360° for 72x5°. This was happening both with the new and the old motor.
So I made some calculations and figured out that I should use 16 steps per rev instead of 13.
But this is highly strange because they used to work with 13 steps per rev. I made some cuts with correct measures configured that way.
I don’t have the faintest idea how the steps per rev may change with time but the thing is, I was able to make correct cuts after calibration.
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Sorry if it is mentioned somewhere, or if it is obvious and I can’t see it. It’s not all the parts, right?
Do I finally get to know what this cool looking project will become 
?
A cat bed? A speaker box? A firepit or pizza oven it is not.
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You guessed! 
It’s a cat house:
But as the rings on this kind of design don’t fit into each other which makes a lot of waste, I’m trying to make it with half rings glued together, like this:
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Are we talking about the z-axis here? I wonder if the set screws on the coupler between the motor and the shaft need to be tightened?
No, no. I’m talking about the main motors.
It’s very strange. They used to turn the proper angle with the calculations (for steps per rev of the output shaft of the gear box) made with 13 pulses per rev on the encoder and now I had to recalculate for 16 steps per rev.
Do you know of any phenomenon of multiplication of the number of magnet poles with time?
It’s a bit farfetched but it’s the only explanation I can think of.
Is that observation with the same FW/GC version?
If the encoder is the same as this one, 16 makes more sense.
The encoder on the amazon motor you posted the link. https://www.yoycart.com/Product/42299022187/
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Yes, you’ve got a point there.
FW and GC is the same: 1.11
Back in January you mentioned looking at these motors, which do seem to have 16 pulse-per-rev encoders. I’m not clear about what changed between then and now, but I know the sprocket-turn buttons you’re using to turn the motors make use of the chain pitch, sprocket teeth to calculate how much to turn the motor shaft, and the encoder pulse settings to let the PID code watch for the appropriate amount of rotation.
If you’ve found a value for the encoder pulse that works, that’s good.
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Could it be that you tested with the faulty motor that then died?
That would a non mystical explanation 
Ignore it and cut that cat-house. This guys can’t wait to see it finished:
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