Electronic problem?

Mostly Printed CNC - MPCNC Troubleshooting
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Hi there cnc maniacs :slight_smile:

im quite clueless in my problem, i build primo version this awesome machine, it works , but dimensions of creations was bad like i want 40mm circle and it cuts 65mm circle… i thoug it will be problem of bad values in Estlcam for step/mm. i let it be for few months and now i want get back into it, but my machine doing weird stuff :stuck_out_tongue:

Im using arduino with cnc shield , estlcam, 12V2A powering ,drv8825 set to 0.7A machine is squared well

Problem is:

if i connect all axis, one of them not working (Z works all time)
if i switch X,Y cables problem moves to second axis…
if i connect X or Y to Z axis … all axis work smooth

if i switch X and Y steppers, problem didnt move to second axis - this pointing to bad wiring
so everything i combined and try… one of axis still “wobble” on spot, must go on lowest speed to move it.
but when i connect one of axis to Z axis all work full speed smooth :confused:

so i try : reprogram arduino, replace cnc shield with other shield, replace this with nano+ramps 1.6 ,move back to shield, change stepper drivers, totally change all wirings but its still same…

in past it works good, i dont know what i did bad to my machine :confused:

i put video here its long and bad, but there you can see the problem how “wobbling”
** ill put it here when it will upload** - slow internet in work :))

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cant paste here video so watch?v=cgRtpyJxQbc on youtube

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Check the stepper wire pairs for that axis. The sounds it’s making sound like one pair is wrong.

5

That’s not a lot of current. Are you sure that the PSU isn’t browning out?

Are you using 20T pulleys, or 16T?

1 Like
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it used to work normally, then start to do this, so propably pairing is okey, because all 5 steppers are same. when i put the axis which not working to Z axis slot, it works good, so thats propably good,
but i will check it :slight_smile:

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it work one week ago normally, but i can switch it to 24v , which shield can handle i think

i use 20T pulleys

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I know a RAMPS shield can’t take 24V (The polyfuses go “pop” at about 16V) I don’t know about those. It’s more current that I would want. I like having a fair amount of overhead in a power supply.

For 20T pulleys steps/mm should be 80 (16X microstepping, say for A4988 drivers) or 160 (32X microstepping, typical for DRV8825 drivers.)

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I´ll try to change power source now i have LED wire powering 12v2a how the cncshield want, but i think it will be same.

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There are several online guides for prepping RAMPS to use 24 V. Replacing the fuses, and removing a diode, are (as I recall) the major modifications.

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I make it works… All cables works ,all stepper works.
Dont know why, but some combination of stepper with wire works… :slight_smile:

I have only last problem, dont know what values put into estlcam to cut to properly depth… a try few settings, but when i want cut 20mm depth i reach just 16mm…

32 microstepping, rod is t8 with 2mm incline ramps 1.6 on arduino mega and using estlcam

Thanks for al advices

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Does the GCode cut to the proper depth?

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It should go as deep as you specify.

Some parameters for the cutting bit will determine how much it can do as a finishing pass, but it will do more than one finishing pass in that case. A single pass cannot be more than the Z+ step value for the tool. If you specify still do it, just in more than one pass.

This should all be on the milling basics page.