Need Help!- Motor & board problems

[ZigMan]

I have purchased an almost finished DIY cnc router from a friend that had to leave town. I think it has 305 oz motors & board setup from HobbyCNC. I made all the right connections and tried to jog the motors today and ran into a little problem. Y axis works perfect, X axis will run and then it will start to jerk, the motor would slow down to almost a stop, and if I stop the movement (in Mach3) it will start again and do it all over again. The Z axis will not move but there is a noise from the motor when jog button is pressed. It will move in real small increments if the steps are set to 0.010 but it will not turn normally. Both of these none working axes are free turning and there is nothing binding them.

I would love to get some info on what might be causing this. I will check the voltage on the board. I think it should be set to 0.42v and my fried told me that it was set ok. I also need to test the rest of the connectors. All of this is less then a year old and it has never been used so it should be working as new.

.........I just tested the board; X and Y settings are at .042V but Z shows 0.26 and it can't be set any higher. The seller had assured me that he had it set to 0.42 and I believe him cause he really did good work on the board and the whole setup.

Thank you.

[sjohnson]

Hi.

The problems could be several things. Here's a checklist to go thru (in this order):
PLEASE TURN OFF THE POWER TO THE WHOLE SYSTEM BEFORE GOING AHEAD!
1) Are all the steppers the same brand? (If so, they should be wired up the same way to their appropriate driver connectors.)

CHECK THE WIRING
2) Assuming they are the same, verify that all the colored leads are all wired up the same at the connector(s) - at the board and any connectors between the steppers and the board. Also check under any electrical taped splices that might be in the middle of each cable to make sure that there are good soldered or connectorized connections under there. They could have pulled loose.)
2B) If they are not the same brand or a known identical substitute, you will need to get wiring information for them in order to make the connections match between the different brands. You can't necessarily rely that every manufacturer uses the same color code for their lead connections internally to the steppers.

CHECK THE STEPPERS AND DRIVER BOARD FUNCTIONALITY
3) If all the connections look good and go to the same places, write down the color codes for the axis that works correctly.
4) (WITH THE POWER OFF) Disconnect all the leads that go to the stepper that is working and connect all the wires that go to one of the troublesome axis steppers to that connector on the driver board. Reconnect the previously working stepper to the driver board where the non-working stepper was.

ie: If X was working and Y was not, swap all the connections for the X over to Y and Y over to X. (At the board connections)

Restore power and test the two axes you just swapped.

TEST THE SYSTEM
- If the non-working stepper now works AND the stepper that did work no longer does, there is a problem with the axis driver on the board for the axis that wont work with either stepper.

- If the non-working stepper still does not work AND the working stepper still does work (but is controlled by the new axis you connected it to) then you probably have a bad stepper.

- If they both work now, you probably had a bad connection to the driver board.

This is not conclusive, but should help you get things isolated to either a board problem, wiring problem or stepper problem.

Good luck and best regards,

Scott

[Jay C]

You never said if you are using his PC. If not, then you need to configure MACH for the motors and the board. Check to see if you have backlash comp turned on. If so, that's another setting to fix.

Jay