I’m dealing with a Z-Dropping issue and can’t pinpoint the cause.
Setup:
Jackpot Control Board with a driver from the v1e-shop
Steppers that are supposedly identical to those from the v1e-shop and should have the same torque
Low-Rider V3
200W Power Supply, not from the v1e-shop
Problem:
The Z-Axis drops occasionally, sometimes just 1 or 2 steps, other times a significant amount >1mm (refer to the second case picture). Typically happens when the Z has been constant for a while and the other axis are working hard.
No noticeable dropping in idle mode with powered steps.
What I’ve tried:
Checked screws on the Z-axis spindle.
Measured the 24V with a basic voltmeter while running (no drops detected).
Now, what should I do?
I’m considering making a flat surface on the spindle to ensure it’s not “rotating” while the stepper is stationary.
Some thoughts:
Could it be that the Steppers aren’t strong enough to hold everything on the Z-axis?
Exempel:
The surface should be constant regarding z to the edge of the circle. The inner hole reflects the second run of this pocket. However, during the first run, the Z-axis dropped on the outer part.
In Klipper I needed to increase my run current for my steppers. I’m not sure if there is something equivalent for you but that solved my z drooping over the course of a cut
My primo will do that if i try and exceed the max feed in z. AKA gitting in a hurry. Also as Rob said check the voltage and be sure the driver isnt overheating also. So much fun (
Details: This value sets the driver’s output current when the driver is not outputing steps.
Do you have any recommendations regarding the value I should use? In the config file, which was shipped with the Jackpot Board the parameter is like the Default 0.5.
I would set the hold amps to 0.68, which would be the same value than for the running amp. Maybe also increase running amps?
My rule of thumb, is run them at a current where they are warm but not too hot to hold my hand on. For me, my run current I believe is around 1.2amps for my steppers. I’m using these Amazon.com
I have not set my hold current separately, I believe you would typically set your hold current if you want it lower than the run current. That might just be Klipper or totally wrong I’m not entirely sure
Ok, I use the same Stepper. I hope this parameter is really controlling the current and is set as Amper. Since that is actually no where written. Nevertheless. I will go to 1 with both holding and running amp and test it today. I will give Feedback afterwards.
Sure thing, good luck! Whenever I change amps (or just every now and then) I’ll run my hand over the steppers just to gauge how hot they are. If they are too hot to touch, think about stepping it down, if they are nice and cool, think about stepping it up.
why fix what isn’t broke? If you wanted to toy with it a bit, like I said earlier, get them to where they are warm but not too hot to hold your hand on them, they can probably live around the same amp as the Z steppers. Remember though, if they are under amped they can skip steps, and if they get too hot they can skip steps, so you are really wanting to find that balance.
Mine are rated 1.8A and I run X at 2A, the others at 1.5A. Even X does not get warm because it’s the peak value the steppers (TB6600) supply and not continuously. I try to find the LowRider’s limits though (and succeeded in finding them).
Anyone already know what’s optimal Nema 17 current, stepper temp, and tmc2209 driver temp range?
Asked ChatGPT, do numbers from ChatGPT seem too high?
ME:
Using a V1 Engineering CNC with Stepper based motion, we want the machine to be faster than Philipp’s CNC.
Help me find optimal settings to maximize motion speed and torque.
For Nema 17 stepper motor, what’s the optimal current to use? What’s the optimal stepper temperature range? What’s the optimal driver temperature range?
What tips and tricks can help maintain that optimal temperature range while boosting current to maximize motion speed and torque?
ChatGPT 4:
To optimize the motion speed and torque of a V1 Engineering CNC using NEMA 17 stepper motors, consider the following factors:
Optimal Current for NEMA 17 Stepper Motors:
The optimal current setting depends on the specific model of the NEMA 17 motor you’re using. Generally, it ranges from 1.2 to 1.5 amps.
Overdriving the motor with higher current can increase torque but may lead to overheating.
Optimal Stepper Motor Temperature Range:
Stepper motors should typically operate below 80°C (176°F). Above this, the motor’s magnets can weaken, leading to a decrease in torque.
Optimal Driver Temperature Range:
Stepper motor drivers should be kept cool, ideally below 50°C (122°F). Overheating can lead to failure or reduced performance.
Tips and Tricks for Maintaining Optimal Temperatures:
Use active cooling, like a fan or heatsinks, on both the stepper motors and drivers.
Ensure good ventilation in the machine’s enclosure.
Adjust current settings to find a balance between performance and heat generation.
Regularly check for any mechanical binding or misalignment in the CNC machine, as these can cause the motors to work harder and heat up.
Increasing Motion Speed and Torque:
Upgrade to a higher voltage power supply if possible, as this can improve torque at higher speeds.
Consider using a geared stepper motor for higher torque at the expense of speed.
Regularly maintain and lubricate all moving parts to reduce friction and improve efficiency.
Remember, the ideal settings can vary depending on the specific application and components used. It’s important to monitor the performance and make adjustments as needed. For specific model recommendations or more detailed adjustments, consulting the manufacturer’s specifications or seeking advice from a community forum specializing in CNC machinery can be very helpful
