idea for improved startup sequence

[tomnagel 79]

Most of the time I print with a heated bed, which takes a few minutes to warm up. The GCode that is generated by Cura makes the printer warm up the bed and the nozzle at the same time. The nozzle is at setpoint within a minute, and starts oozing for a few minutes, because the bed is not ready yet. This causes a bad start of the print.

The trick that I am doing manually is that I put the (glass) bed against the nozzle, so that it is closed. I do this when the nozzle is at the XY home position. This is important, otherwise the homing action of the printer after heating would drag the head accross the glass bed to the home position.

Today, I thought that this simple trick (closing the nozzle with the glass bed) could be done automatically. This might be built into Cura.

How do other folks handle the oozing of the nozzle during heating of the bed?

 

[Dim3nsioneer 484]

As I have an UM1 with a heated bed, I work in RepRap flavour. Thus, I have a start.gcode where I can determine the order in which hotend and bed are heated. I first heat the bed and then the hotend, so I don't have any significant oozing.

The same thing would be possible with an UM2 when the flavour is switched to RepRap from UltiGCode.

 

[IRobertI 441]

I'm assuming this is on an UM2 since you mention a heated bed? If so, when did you last update the firmware? The heat-up sequence has been that the bed starts heating up and the head doesn't heat up until the bed is almost up to temperature for quite some time now.

 

[eldrick 62]

That's a good way to crack the glass from the point heated by the extruder.

 

[gr5 1,293]

The latest firmware may help you as Robert suggests.

 

[tomnagel 79]

I have a home made heated bed on an UM1. I use hardened glass, so I don't think the hot nozzle against the plate is a problem.

I'll modify the startup lines to heat up the bed first.

Related question; what does T0 mean in the line

 

M109 T0 S190.000000

 

[Daid 297]

T0 means "extruder 1"

I made the "heat heads and bed at the same time" before I had experience with heated beds. Now I think there are better startup sequences. But I haven't got around to change it yet.