Hi, New Geeetech i3 Pro C and I could use some guidance!

Hi all,

I just picked up a new Geeetech i3 Pro C and I'm trying to figure out how to get it set up. I have worked with all kinds of electronics over the years and have a good grasp of how stuff works, it's just the set up that's getting to me. Here are some questions and maybe someone can help me out a little?

Here is some information to let you know where I am at.

I have the latest Marlin firmware loaded for the GT2560 controller, I'm using Repetier and have control of the motors, fans, heaters, etc. Motors work fine, no noise, nothing strange. Heaters all work ok, temp is good. There are limit switches installed on the min side of the x,y,z axis, but if I move the motors using Repetier in manual control and I push the limit switch in it doesn't stop the travel. I assume the configuration H is not set up correctly, but I have some questions concerning other parts of configuration h also.

Configuration H,

1. I have "#define MOTHERBOARD 7" but should it be MOTHERBOARD 34 since I have 2 extruders and the heated bed? I don't see a description for #7, so I'm not sure it's a big deal.

2. I assume that the limit switches are not set up correctly since they don't stop the motor during manual control travel. So, I would need to edit configuration h but I'm not sure what to change. The switches are wired as NC and they do open when the switch is pushed in.

I think I just change the min_endstop to true for the X, Y, Z axis since I don't have limits on the max end stops?

const bool X_MIN_ENDSTOP_INVERTING = false; // set to true to invert the logic of the endstop.
const bool Y_MIN_ENDSTOP_INVERTING = false; // set to true to invert the logic of the endstop.
const bool Z_MIN_ENDSTOP_INVERTING = false; // set to true to invert the logic of the endstop.
const bool X_MAX_ENDSTOP_INVERTING = false; // set to true to invert the logic of the endstop.
const bool Y_MAX_ENDSTOP_INVERTING = false; // set to true to invert the logic of the endstop.
const bool Z_MAX_ENDSTOP_INVERTING = false;



3. Once I get the limit switches working I have a question. If operating the Y axis travel and it goes all the way to the limit switch then both the extruder heads are a little off the bed, with X axis min limit switch activated as the carriage is to the left then the #1 extruder head will be off the bed, and #2 extruder will be off the bed at the max amount of travel (to the right) at supposedly 200mm. How do I define the max travel so I don't go off the bed in Y and X axis? If I set the min endpoint before it gets to where the limit is activated on the X and Y axis, then couldn't I just measure over to a point that all extruders are always over the bed and use that for the definitions below?


#define X_MAX_POS 210 (after changing X min below, I would think that I would change X max to like 160mm to keep the #2 extruder over the bed)
#define X_MIN_POS 0 (make this a positive number like 10mm to keep the #1 extruder over the bed?)
#define Y_MAX_POS 210
#define Y_MIN_POS 0
#define Z_MAX_POS 180
#define Z_MIN_POS 0

4. For the Z travel, should the limit switch be set so that when the extruder is just touching the bed (1-2 piece of paper thick distance) then the switch is activated? And I assume that I need to calibrate the bed to be leveled at this minimum distance between all 4 corners of the bed and the extruders.

I apologize for my long post, I really could use some help and although I am electrically, mechanically not a noob, this is really new to me...lol.

Thanks!

To update my post..... btw, I bought this off of craigslist, so it was already assembled, but I went through most of it and thought it looked ok, it was never used....

1. I found that the limit switches were plugged into X, Y, Z max, not min. That solved the switches not working. The carriage moves to each axis and stops
2. I adjusted the bed wayyy down, it was too high. Then I adjusted the limit switch so the lowest extruder wouldn't hit the glass. I got the #1 extruder 2mm off the bed, #2 is about 2.5mm and I'm trying to figure out how to lower it.


I'm still wondering about the max travel length as it puts an extruder off the glass bed for X+ max for #2 extruder and X-min for #1 extruder, Y-min puts both extruders off the glass. Any feedback?

Dual extruder huh, now I'm thinking that to achieve maximum print volume as much as you can, each nozzle should be well calibrated especially the offset locations. If either one of the nozzle for example extruder 1 is off the glass while extruder 2 is at the edge (on x min) while it is the other way around on x max, this however utilises maximum build area

Don't worry about the nozzle is off the glass when it is homed, mine is off the glass and I preferred this way, I don't have auto bed leveling and my bed were perfectly leveled last time with 0 z axis home offset. At least you can avoid from your heatbreak to actually break when the z home not well calibrated.

I use z home offset to quickly solve my bed/z home height being somewhat "varied in time"

Hope this helps

Q#4) My understanding is that when you choose auto-level the extruder moves to four points away from the center
and drops until the motor load goes up (because it touched the glass) and uses those points to calculate a plane
for the bed.

Update about extruder height:
The extruders should be at the same height.
It may be easier to shim the lower one up than to go the other way.