Ball screw upgrade help??

ziggymanpopo

I instaled. a ball screw to get rid of ringing on a cr10 s5 frame. Not much left on it thats actualy creality

This has been a great experience that i continue to enjoy learning.. i could use some sugestion and advive.. The ballscrew is working and i can move it. After it homes. I notice its trying to home in the wrong drectoin wich i can easly fix. What i found interesting is she goes a little way and then stopes. Almost like it sensed a stall prematurely.When i instaled an inductive b l. Sensor the end switches Quit working and started to hit considerably harder on the endstops ( assuming stall feature) but it works. So my questions would be. As follows.
Wher do i neet to set my seppers at to get this to work properly.
It is a 16/05 ballscrew that I'm using for my y axes
Where would i set my acceleration jerk. And steps per mm. ( i came ip with 640ms and would it be advisable to change to 1/8
Interpoling insted of 1/16th for tork?? )
I am concerned that if it did home all the way wloud the ballscrew work on end stop stall like before or does that need setting adjustments or do i need to go back to a mechanical endstop system ??
Thanks for the input in advance. Ed
Fwi i am running a duet2 wi fi
Great board!!

Phaedrux

I'm not really sure what's going on. It sounds like you're using stall detection as an endstop, and you've replaced the Y axis belt with a ball screw, and now it's hitting the stop a lot harder than before.

Perhaps part of the difference in the behavior is that you no longer have the belt to absorb some of the forces.

The ball screw will also likely require some very different acceleration and jerk settings due to the rotational inertia of the rapidly spinning screw. In fact, if your goal was reducing ringing I'm not sure a ball screw was the right way to go, since you'll need to reduce speed to do that and probably beyond the reduction you would have needed with a belt.

@ziggymanpopo said in Ball screw upgrade help??:

Wher do i neet to set my seppers at to get this to work properly.

Everything is configured in config.g

@ziggymanpopo said in Ball screw upgrade help??:

Where would i set my acceleration jerk. And steps per mm.

M201 for accel, M566 for jerk, Steps per mm in M92

Use this formula to find your steps per mm for a lead screw driven axis:
Z_steps_per_mm = (motor_steps_per_rev * driver_microstep) / screw_lead

Do you know the "lead" of your ball screw? How much movement do you get from a single full rotation?

@ziggymanpopo said in Ball screw upgrade help??:

would it be advisable to change to 1/8
Interpoling insted of 1/16th for tork?? )

Stick with x16 with interpolation enabled.

@ziggymanpopo said in Ball screw upgrade help??:

I am concerned that if it did home all the way wloud the ballscrew work on end stop stall like before or does that need setting adjustments or do i need to go back to a mechanical endstop system ??

Personally I'm not a fan of bashing the print mechanism into the frame to home the printer. I would rather have a reliable endstop switch.

3DPMicro

That 5mm lead ball screw is going to provide significantly more force multiplication than a belt/pulley set up so the stall detection is going to loose sensitivity. Do the math and you'll see. I can stall my belt driven printer by hand. My ballscrew printer with 6mm lead stalls at 18kg of force with the same nema 17's. My 1mm lead ball screw cnc micro mill creates 8kg of force from dinky 20 oz/in nema 14's

mrehorstdmd

Isn't the usual way to use stall detect as an endstop for homing to reduce the speed and the current and thus the torque/force?

I used a ball screw in a printer's Y axis for a couple years. It did stop ringing in prints but there was a mechanical resonance I could never eliminate so the machine was limited to 40 mm/sec maximum speed in Y. Even with the speed limited, it was noisy. I ended up leaving the machine at the makerspace because my wife wouldn't stop complaining about the noise. Then I built UMMD.

Phaedrux

@mrehorstdmd said in Ball screw upgrade help??:

reduce the speed

I think it's actually increase the speed so there is enough backemf to detect.

ziggymanpopo

Taking in what you guys have to say. the pich unfortunately is a 5mm pitch. I would have prefered 10mm pich but not one avalable so to the one gentleman who asked. ,the pich is 5mm per rev. Im not a fan of the slaming either. X and y in my opinion hit way to hard. That was with stall.. the end sw. For both are deactivated x doesnt iether. When i instaled the capasitive bed levals sensor. The code was changed as part of the process
How does one reactivate that functoin for the end sw. ...And Should I ??? Would it be better just to change the stall settings?? And would it be a thing to use the stall feature as a backup?
Specificly what values should i use for the following

Acceleration... some suggest beteen 2 To 3 hundred ???
Jerk... also 2to3 hundred ???
Theese are figuare i got from research but nothing to bach it up

And micro stepping. This is the math i could find on ms. /mm......... 640ms. Based on this math
200x16÷5=640 MS... Hope thats right.
Thsnks for the input. Again

ziggymanpopo

My other concern was like the other gentleman said was with increased forces that the ball screw creates i was woried that it might pull the bearing right out of the end block with the constantly slamming into home