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Topic: X stopped working after VREF tweak

Hi,
I was tweaking my X VREF trim pots when my X all of a sudden stopped responding. I thought somehow I tweaked the trim pot one too many times as I like to do it by ear. Thinking I burned out the motor, I ordered a new one. When I plugged it into the board, the new one didn't respond to Reptier commands either. Now I'm wondering if it is the board or the stepper chip? Y and Z respond fine so I am a bit stumped. I have a ATMega 644P/Sanguinololu board on my SD3. Any help would be greatly appreciated as I am currently out of commission.

Thanks!

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Re: X stopped working after VREF tweak

Your  VREF is probably just too far off.  Try checking the voltage and set it according to the WIKI.  I have had the samething happen on that same board for the z axis.  I think the stepper driver overheats and shuts itself down.

Printit Industries Model 8.10 fully enclosed CoreXY, Chamber heat
3-SD3's & a Workbench all fully enclosed, RH-Slic3r Win7pro, E3D V6, Volcano & Cyclops Hot End
SSR/500W AC Heated Glass Bed, Linear bearings on SS rods. Direct Drive Y-axis, BulldogXL
Thanks to all for your contributions

3

Re: X stopped working after VREF tweak

Or, if you used a metal screwdriver, you could have shorted out a spot on your printer board. Best to use a non-conductive screwdriver for those adjustments on the board.

SD2 Expert stock, ABS fume fan,
XYZ DaVinci 1.0 stock ABS, Simplify3D
QUBD Two-Up PLA, new 3D printed X gantry, Y idler, flex z coupler, extruder mount, E3D Lite

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Re: X stopped working after VREF tweak

I adjusted it exactly to what the Wiki suggests and it's still not responding. If I did somehow short it out, do I have to replace the whole board or would it just be the steppers?

5

Re: X stopped working after VREF tweak

Just the daughterboard, they're like $10 from pololu.

http://www.pololu.com/product/1182

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Re: X stopped working after VREF tweak

Good time to upgrade to an 8825.

Printit Industries Model 8.10 fully enclosed CoreXY, Chamber heat
3-SD3's & a Workbench all fully enclosed, RH-Slic3r Win7pro, E3D V6, Volcano & Cyclops Hot End
SSR/500W AC Heated Glass Bed, Linear bearings on SS rods. Direct Drive Y-axis, BulldogXL
Thanks to all for your contributions

7

Re: X stopped working after VREF tweak

I ordered a new stepper driver. Thanks for that. Everything I have been reading about replacing them says they just pop off. Can anyone give me specific advice on how/where to leverage something to pop it off? I really don't feel like breaking anything else. If this works, I will upgrade to the 1/32 drivers although I believe I will have to change something in the code and upload the firmware change, correct? Would this be the right one? http://www.pololu.com/product/2133

Thanks.

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Re: X stopped working after VREF tweak

That one will work all you need to do is change the steps in EEPROM (double).
You should be able to just pull the old one out and plug in the new one.

Printit Industries Model 8.10 fully enclosed CoreXY, Chamber heat
3-SD3's & a Workbench all fully enclosed, RH-Slic3r Win7pro, E3D V6, Volcano & Cyclops Hot End
SSR/500W AC Heated Glass Bed, Linear bearings on SS rods. Direct Drive Y-axis, BulldogXL
Thanks to all for your contributions

9

Re: X stopped working after VREF tweak

I got my stepper driver today. I just want to make sure I'm installing it correctly. It looks like I need to solder the pins onto the new board. I'm not great with a soldering iron and with 8 small pins on each side, I can't imagine I won't get some solder on something. Is this right? Thanks.

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Re: X stopped working after VREF tweak

For that one you need to solder on the pins.  Put the pins through the board heat a pin near the board.  Touch the solder to the pin at the board and when it's hot enough it should flow nicely into the hole around the pin.  Repeat till your done.

Printit Industries Model 8.10 fully enclosed CoreXY, Chamber heat
3-SD3's & a Workbench all fully enclosed, RH-Slic3r Win7pro, E3D V6, Volcano & Cyclops Hot End
SSR/500W AC Heated Glass Bed, Linear bearings on SS rods. Direct Drive Y-axis, BulldogXL
Thanks to all for your contributions

11

Re: X stopped working after VREF tweak

Hi guys,
I was hoping someone could just check my steps to make sure I wasn't missing anything while replacing my 1/16 stepper drivers to the DVR8825 drivers. Here is what I'm planning to do:

1. I bought 4 new drivers on recommendation from Pololu here: http://www.eckertech.com/pololu-drv8825 … ed-tested/
2. Replace all 4 drivers on the board
3. Multiply all 4 numbers by 2 in this line of the configuration.h file - #define DEFAULT_AXIS_STEPS_PER_UNIT   {88,88,2268,96.6}  //{SD Patch} // default steps per unit for ultimaSker


Is there anything I'm missing? I didn't see any other steps on the forum. Thanks for your help.

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Re: X stopped working after VREF tweak

you only need to change the steps-per-mm in EEPROM ; either via repetier's dialog (non-mac) or via the M50X commands (on a mac).

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Re: X stopped working after VREF tweak

Hi Adrian,
Yes I am on a Mac so the EEPROM window doesn't come up. So what exactly would I type in the manual G-Code field in Repetier to change all 4? Sorry, just don't want to screw it up. Thanks.

14 (edited by adrian 2014-08-10 15:17:14)

Re: X stopped working after VREF tweak

Just go to the manual tab and type in something similar to:
M92 X80.00 Y88.00 Z1000.00 E990.00

adjusting the values as required of course smile M501 will tell you what they are at the moment.

You then type M500 to store those values in EEPROM.
M501 will read back all current values in the EEPROM; just retype the various lines to adjust them and then M500 to store.
The messages appear in repetiers log window of course btw.

If you want help on a specific G-code; http://reprap.org/wiki/G-code is a handy reference

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Re: X stopped working after VREF tweak

Thanks, Adrian. I'm going to give this a try as soon as the steppers arrive.

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Re: X stopped working after VREF tweak

So I installed the new drivers and they seem to be working, however when I went to use the multimeter, I slipped and shorted one out. Good think I bought extra. I basically did the same thing as the wiki instructs, but I think that's how I burned the stock driver out. Is there a safer place to put the negative lead from the multimeter? I know the positive goes in the little notch I have circled on the attached pic, but is there a better place for the negative that won't short the driver out? Otherwise the only option is by ear.

Thanks!

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Re: X stopped working after VREF tweak

Any ground on the board will work.

Printit Industries Model 8.10 fully enclosed CoreXY, Chamber heat
3-SD3's & a Workbench all fully enclosed, RH-Slic3r Win7pro, E3D V6, Volcano & Cyclops Hot End
SSR/500W AC Heated Glass Bed, Linear bearings on SS rods. Direct Drive Y-axis, BulldogXL
Thanks to all for your contributions