wrong travel range (z) @ Rostock - Marlin

Hi there,

I'm new in the 3D-printer-scene and got some issues calibrating my printer.

After finaly everything is set up for the first movements and tests, i got problems with the travelled distance.

Setup:
Selfmade Printer, orrientated on the Rostock delta-printer
Motherboard: Ramps 1.4
Stepper: 1.8 ° (200 Steps/rev)
Firmware Marlin (see atached files for Config)

1st Problem:

I got 20 tooth pulleys running with a GT2 belt.... and set 80 steps per mm in config.
When I meassure the travelled distance after pushing the button "1" for z axis down in Pronterface,
the carrier doesn't go down 1 mm (or cm, I don't know what scale pronterface uses for manual movement) but rather about 16mm.
If I check the distance in pronterface (M114) it tells me, that it went down for 1mm.

I got the A4988 on the board and the microstepping mode is set to 1/16 (see attached files).
I really dont know where the difference in distance comes from.

2nd Problem:

When I power up everything, connect the Arduino to pronterface and press the Home-button, all axis move toward the endstops. The first axis which triggers the endstop starts beeping untill I manually hit an endstop (not the one for the beeping axis). After that the axis (the one I hit the endstop) starts slowly to do the pullup untill it stops.

...clueless

Thanks for any help

Lukas

Okay ...

kind of fixed it.

It seems to be the microstepping.

I switched it in configuration.h and configuration_adv.h to fullstep and adjusted the steps per unit to 5.

Now everything works correctly.

I got a ramps kit (http://www.amazon.de/gp/product/B00EDG0NK4/ref=oh_details_o05_s00_i00?ie=UTF8&psc=1) which includes the A4988 stepper driver.
This stepper driver should be able to use 1/16 microstepping.

I only got the right results with fullsteps. Tried 1/8 microstepping, but didnt work.

Fullstep means Jumper 1, 2 and 3 off. If the jumpers would be damaged, it would explain why it is only possible to go by fullstep mode.

How can I meassure if the jumpers work correctly?

Or what could I do?

The jumpers just connect two pins together. You can check them for continuity with a multimeter, with 0 (zero) ohms resistance being correct.

I'm surprised that you received a SainSmart kit that included jumpers. The Megatronics 2.0 kit that I purchased from them did not include the stepper motor jumpers, plugs for the stepper motor wires, or instructions of any kind.....

I checked the connection on Ramps with my multimeter, they are all fine.
I checked the pins on the stepper driver with the multimeter(continuity tester) (bottom of the pins to the soldering on top)...all good.
I checked the connection like in the attached file (MS1 stepper Driver to MS1) ...every connection is good.



Why do they not work in 1/16 Microstepping mode but in full step mode???

please help

Lukas

Hi,

I know now for sure, that if I'm in 1/16 Microstepping mode (#define MICROSTEP_MODES {16,16,16,16,16} // [1,2,4,8,16]), the pins MS1 MS2 MS3 don't get the logic-voltage.
The meassured Voltage between VDD and Ground on the driver is 5V.

Is this a hardware fault on Ramps or a software fault in marlin?
I'd like to know if there is any other way exept "#define MICROSTEP_MODES {16,16,16,16,16} // [1,2,4,8,16]" to set the wrong microstepping mode?

Otherwise I'm going to solder a wire connection on the driver from vdd to MS1 MS2 MS3 to set the driver in microstepping manualy.

Please help!

Lukas

Okay, Problem solved.
The thing was, trhat I didn't realy know what actually a juper is.
I thought it would be just the black plastig thing where the pins come out.
So I didn't have jumpers connected to MS1 MS2 MS3.
Just bought some today and now everything works just fine.

Thanks for the help anyway.

Lukas