Zeroing the Rostock Max

[ashish]

I can control the Rostock Max using the manual controls in Repetier.
How do I zero the Machine, ie how do I tell the machine where the x,y,z origin is?.
I tried to manually place the hot end at the correct position, then connect to Rostock Max, using Repetier.
But If I try to print the calibration pyramid, The machine first sends all the carriages to the max position. Waits there for the hot end to heat up and then comes down to about 10mm above the surface of the heated bed and starts printing. I have tried changing the size of the machine to 355mm but that did not fix the issue.

Also My heated bed has a hard time reaching 110 deg C, but at that temp, the krylon plastic, is bubbling. so I am wondering if the thermistor which is mounted to one end of the PCB is not reading the correct temp?.


-Thanks
ashish

[Polygonhell]

I wouldn't trust bed thermisters to be accurate, placement makes an enormous difference.
For example the thermister on my Mendel Max is under the bed and reads 85 degrees when the top of the bed is at 110, doesn't matter I just set the temperature to 85 instead of 110.
Measure it on the top of the bead at the center with either an IR thermometer or better a thermocouple connected to a multimeter.

[barnett]

Hi,

I have a similar question here. I calibrated the z axis per the newly updated info on the Reprap wiki page and it worked great. I now connect to the machine in Repetier, send G28, jog down to 0.1 in Z and I'm right at a piece a paper width above the stickralon plate on the heated bed.

But X and Y are not saying zero even though the platform is centered. They are saying -79 and -87 (corresponding to my bed left/front positions). When I jog +79 in X from the center I get to the edge of the plate on the heated bed - actually a little short of the edge to allow for where the clips touch the plate. Similar for jogging +87 from center in Y.

The Reprap wiki says this:

4. Also while in the Printer Shape tab, we need to change Home X and Home Y to 0 instead of Min or Max, and Home Z to Max.

Not sure where to set home to zero. Firmware has 0 for X & Y home position and 337.2 for Z:

Code: Select all

// The home position of the print head.
// For Rostock this means top and center of the cartesian print volume.
#define X_HOME_POS 0
#define Y_HOME_POS 0
#define Z_HOME_POS 337.20 // Distance between nozzle and print surface after homing.

My Printer Settings | Dimensions tab is attached. This is Repetier Host for Macintosh version 0.51 (47).

Repetier: Printer Settings, Dimension tab

Thanks!
Barnett

[johnoly99]

Hey guys. To set the zero, you home the machine, you can do this one of two ways, the easiest is to just type G28 in the manual tab and press enter. That will send the three arms up, and they will home individually once the first arm touches an endstop. The other way is to jog up close, and press the Home icon in repetier. Do this one carfully though. By default, clicking the home button in repetier send G28 X Y Z, which will home the X tower, then Y, then Z. If your platform is close to the table, this can cause the platform to crash into the towers. G28 only uses what is called 'quick home' where all 3 axes move until one has triggered an endstop, then they home X, Y Z seperately

[barnett]

Sending G28 moves the carriages as you describe, and Z shows the Max position of 337.2 for me. But X shows -125 and Y shows -125 even though the platform is centered.

I can try the home button as you suggest though. Thanks.

[johnoly99]

Ahh, barnett, in repetier, open config-printer settings and in printer shape tab, set x home positiin and y to 0

[barnett]

I suspect the Mac version is different from the Windows version.

I'm not finding a Config menu but I do have a Printer Settings in the Printer menu (also accessible from an icon along the top).

In Printer Settings I don't have "Printer Shape" but I do have "Dimension". A screenshot of that tab is in my post from yesterday. It's not clear how to set home position to zero there.

I could try posting to Repetier.com or someplace else?

[barnett]

FYI: here's the reply from Repadmin to my inquiry at Repetier.com.

Indeed the Mac Host has not the needed setting. The windows host has already a setting 0 for this. Will add this for the next release if I don’t forget it For now you have to ignore the wrong resulting preview. The print will not be effected from this.