Fixing the Automatic Chamber Vent
The auto chamber vent works well and props by the way to @Jürgen for coming up with the original idea. However, Prusa's implementation has issues. For starters, the vent is only opened or closed when the filament is changed and during an initial print. Subsequent prints do not open (or close) the vent. This can be a problem, if say for example, you run PLA and accidentally close the vent between prints. The follow g-code modification will automatically open or close the vent on every print regardless of the vent state and close the vent at the end of the print. For reference the new M code M870 O opens the vent and M870 C closes the vent. If you find these commands doing the opposite, i.e. O instead closes the vent, make sure the grill was turned over when reinstalling it. The knob that move the vent (not sure what to call it) has to be over a closed slot, not an open slot.
Add the following to the Start G-code section between the G28 and chamber temp section g-code
G28 ; home all without mesh bed level
M870 {if filament_type[initial_tool] =~ /.*(PLA|PETG|FLEX).*/}O{else}C{endif} ; Open vent for low temp materials
{if chamber_minimal_temperature[initial_tool]!=0}
Add the following to the End G-code section after the first line
{if layer_z < max_print_height}G1 Z{z_offset+min(max_layer_z+1, max_print_height)} F720 ; Move print head up{endif}
M870 C ; close vent
M104 S0 ; turn off temperature
RE: Fixing the Automatic Chamber Vent
One more thing to point out. If you use any of the left-hand side nozzle wiper mods, it may result in a collision with the vent mechanism and will possibly close the vent or leave it in an unusable state. I would suggest switching to a right-hand side nozzle wiper in this case.
RE: Fixing the Automatic Chamber Vent
One more thing to point out. If you use any of the left-hand side nozzle wiper mods, it may result in a collision with the vent mechanism and will possibly close the vent or leave it in an unusable state. I would suggest switching to a right-hand side nozzle wiper in this case.
I'm using a left-side nozzle wiper and the Jürgen auto-vent, and both work together well. To avoid any collision, here is the cleaning routine:
G0 X40 Y-18 Z1.5 F10000; G0 X80 Y-14 Z1.5 F10000; G0 X40 Y-18 Z1.5 F10000; G0 X80 Y-14 Z1.5 F10000; G0 X40 Y-18 Z1.5 F10000; G0 X200 Y-18 Z4 F10000; G29 P9 X208 Y-2.5 W32 H4
RE: Fixing the Automatic Chamber Vent
The auto chamber vent works well and props by the way to @Jürgen for coming up with the original idea. However, Prusa's implementation has issues. For starters, the vent is only opened or closed when the filament is changed and during an initial print. Subsequent prints do not open (or close) the vent.
I believe you only need the M870 C in the End G-code. The firmware stores the current position of the vent and only changes it when the current chamber setpoint is under 45 degrees.
RE: Fixing the Automatic Chamber Vent
The auto chamber vent works well and props by the way to @Jürgen for coming up with the original idea. However, Prusa's implementation has issues. For starters, the vent is only opened or closed when the filament is changed and during an initial print. Subsequent prints do not open (or close) the vent.
I believe you only need the M870 C in the End G-code. The firmware stores the current position of the vent and only changes it when the current chamber setpoint is under 45 degrees.
That only works well if you never close the vent manually, for someone like me that prefer to keep the vent closed between prints to keep dust and dirt from the workshop out this mod only makes sense if it secures the correct open/closed vent regardless of what happened since the last print.
/Anders
RE: Fixing the Automatic Chamber Vent
The auto chamber vent works well and props by the way to @Jürgen for coming up with the original idea. However, Prusa's implementation has issues. For starters, the vent is only opened or closed when the filament is changed and during an initial print. Subsequent prints do not open (or close) the vent.
I believe you only need the M870 C in the End G-code. The firmware stores the current position of the vent and only changes it when the current chamber setpoint is under 45 degrees.
That only works well if you never close the vent manually, for someone like me that prefer to keep the vent closed between prints to keep dust and dirt from the workshop out this mod only makes sense if it secures the correct open/closed vent regardless of what happened since the last print.
Oh, you are right! I didn't think that one completely through. It doesn't work if the vent is somehow opened between prints.
I too keep the vent closed between prints, but I never move it manually.
RE: Fixing the Automatic Chamber Vent
The auto chamber vent works well and props by the way to @Jürgen for coming up with the original idea. However, Prusa's implementation has issues. For starters, the vent is only opened or closed when the filament is changed and during an initial print. Subsequent prints do not open (or close) the vent.
I believe you only need the M870 C in the End G-code. The firmware stores the current position of the vent and only changes it when the current chamber setpoint is under 45 degrees.
I have the magnetic top mod with a lever in front to make it easier to manually open/close the vent. I've quiet often accidentally bumped it between prints (I suppose I'm clumsy) and ruined a PLA print or clogged a nozzle. There was another instance where I took off the top between prints, stored the top on it's side and gravity shut the vent (perhaps it was just too loose). Regardless, the above maybe useful for some people but not for others.
There are also plastics where I don't need a heated chamber but I do want the vent closed because of the smell (or whatever noxious fumes it's giving off). In this case I'll be creating custom names for the filament type. I'm currently experimenting with some exotic tribo filaments and prefer not to have an open vent. I can certainly manually open and close as before but I have a tendency to forgot which is why this auto approach is neat.
RE: Fixing the Automatic Chamber Vent
I'm using a left-side nozzle wiper and the Jürgen auto-vent, and both work together well. To avoid any collision, here is the cleaning routine:
G0 X40 Y-18 Z1.5 F10000; G0 X80 Y-14 Z1.5 F10000; G0 X40 Y-18 Z1.5 F10000; G0 X80 Y-14 Z1.5 F10000; G0 X40 Y-18 Z1.5 F10000; G0 X200 Y-18 Z4 F10000; G29 P9 X208 Y-2.5 W32 H4
There are a lot of wiper mods so it will depend on which one you are using. The one I'm using is specifically compatible with BIQU Cryogrip plates but is not compatible with the Core One + vent mod. In my case, I had to choose the right side option instead.
RE: Fixing the Automatic Chamber Vent
Ok so I've looked into the gcode and logic a bit, i think that your code is pretty good but i would set it using the minimal chamber temp. The start Gcode (as far as i can tell) is using this as a variable to determin if the printer should heat up to a specific chamber temperature before starting the print, this would have the benefit of also respecting other materials like PCTG or COPE as well as custom filaments (if you set the minimal chamber temp to 0). Also you're able to change these settings without adding the filament tag into the gcode.
M870 {if chamber_minimal_temperature[initial_tool] !=0}C{else}O{endif}
I've added this line at the same spot (directly afer G28) as the original by hyiger and it works as intended.
RE: Fixing the Automatic Chamber Vent
Makes sense. Thanks
RE: Fixing the Automatic Chamber Vent
Your G-Code works fine.
Thank's 😉