Help! S4 stops print in middle of bed before it starts,

I'm running Repetier on a mac. I don't think it is a communications error (drivers or physical connection) because all normal operations work. I can turn on and off the heat to the bed/extruder. I can move the extruder/bed via the print panel menu. I can even run individual lines of gcode from the print panel.

I think it has to do with the gcode generation or something? When I start a print the extruder moves to the center of the print bed and then just stays stationary. So it clearly is getting the commands but something is happening before the extrusion happens (post extruder moving to middle of bed but before the skirt is printed).

No errors in the log. I can also extrude manually from the print panel.

Probable!

Check all hot end connections and wiring and make sure no wires are moving relative to the hot end when the carriage moves...as n2ri wrote, maybe your shorting out or disconnecting momentarily during the 1st move.

Instead of just trying to describe it over and over I recorded two videos for you guys. First video is of what happens when I run a print, second is a video of my manually moving the printer head to the center and extruding.

Running some print:
dropbox.com/s/fzyrbnkg6ylqnd1/2014-11-12%2017.04.29.mov?dl=0

Manual movement to center and extrusion:
dropbox.com/s/l3gts8ar40y8ryd/2014-11-12%2017.05.51.mov?dl=0

Here is everything that happens before the first X/Y movements.

Start code:

G21; Set units to milimeters 
G90; Set absolute coordinates 
G92 E0; Reset extruder 
G28 X0 Y0; Home x and y axis 
G1 X100 Y100 F4000; Center extruder above bed 
G28 Z0; Home Z axis 
G1 F3000; Set feed rate (speed) for first move

Sliced gcode:

; generated by Slic3r 0.9.9 on 2014-11-12 at 17:53:31

; Please note that the first layer is set at 0.35mm to avoid sticking and warping issues. For further precision, consider adjusting this value to 0.3mm.

; layer_height = 0.3
; perimeters = 4
; top_solid_layers = 3
; bottom_solid_layers = 3
; fill_density = .2
; perimeter_speed = 60
; infill_speed = 60
; travel_speed = 75
; nozzle_diameter = .4
; filament_diameter = 1.68
; extrusion_multiplier = .6
; perimeters extrusion width = 0.42mm
; infill extrusion width = 0.42mm
; solid infill extrusion width = 0.42mm
; top infill extrusion width = 0.42mm
; first layer extrusion width = 0.42mm

G21 ; set units to millimeters
M107
M190 S115 ; wait for bed temperature to be reached
M104 S195 ; set temperature

M109 S195 ; wait for temperature to be reached
G90 ; use absolute coordinates
G92 E0
M82 ; use absolute distances for extrusion
G1 F9000.000 E-2.50000
G92 E0
G1 Z0.350 F4500.000

I tried it. Nothing changed. I have it echoing the lines as it goes through them, and no matter what lines I comment out it just hangs before it gets to the actual print.
The last line it echos when I take out the M190 line is the G92 E0 line.
So I tried commenting out that as well and it hangs on M82.
When I comment that out it hangs on G92 E0 again.
When I comment that out it hangs on the G1 line.
If I comment that out it just hangs earlier back at the G90 line.

Smarch,  I will need to check your code against mine, but I cannot get to it tonight...I'm remote from my machine and I've got a ton of CAD work to do for my day job

Some other more Code-worthy members please weigh in!

In the meantime, read through this topic:

http://www.soliforum.com/topic/397/too- … ing-wrong/

Might be some nugget in there for you...it's a bit dated, but code is code.

I appreciate it! Thanks again for the help.

Still sounds like sometning you need to address. For some reason your host or the printer is halting and failing to resume after a blocking call for temperature checks. You should try another version of RH or a different host. But you should definitely find the cause. Your printer shouldn't do that. It should successfully unblock after a target temperature has been reached.

In the meantime be cautious of heating up the hotend for too long before a print starts. The stock hotend is sensitive and could clog if left hot and not extruding for 15-20 minutes.