Anyone Use Custom G-Code Commands

Does anyone use custom G-Code Commands when printing objects? I know some people use custom commands to start and/or finish their print outs. I'd like to know of any that you people have found useful.
James

Here's what we use; I'm not sure which of them are custom:

Gcode Basics

Start Gcode

This code should be at the beginning of every Gcode file:

Code:

M757 S[nozzle_diameter] ;set layer/path width M729 S3 ;set 16 step mode M758 S0.095 ;set steps/nL M734 S60 ;set error reporting interval for redundant errors to every 60 seconds

End Gcode

This code should be at the end of every Gcode file:

Code:

;M721 ;unprime M103 ;stop extrusion M104 T10 S0 ;turn off all extruders M140 S0 ;turn off hotbed

Layer Changes

Please also note, that if you want to take advantage of several new features regarding layer change options, ( I.E. pause at end of layer, take picture, etc) you will want to add the M790 to the layer change G-Code as well:

Code:

M790 ;announce new layer

Everything

Here is code that should be in EVERY recipe:

Code:

;now we set up for any build offsets that we may want G21 ; use millimeters G90 ; absolute coordinates G0 Z5 ; lift head to avoid collisions G28 X0 Y0 ;always home before starting a build home X and Y G0 X0 Y0 ; move to desired origin, necessary if you want a negative offset G92 X0 Y0 ; reset origin:to new X and Y, it is legal to add values to x an y, I.e. X30 Y40 will ;set the current location to X30 an Y40 M83 ; relative extruder coordinates ;set up Head Flow characteristics M6 T10 ; select all heads on yoke 1 ;M227 ; enable unprime/prime on non printing moves M221 S1.0 ; set fudge factor for extruder to 1.0 M756 S[first_layer_height] ; set first layer thickness M757 S[nozzle_diameter] ; set layer/path width M729 S3 ; set 16 step mode ;set the pulses per unit volume, this is different depending on extruder type ;and material size, I.e if the 1.75mm filament is really 1.65, you can adjust this number ;Or the Fudge factor M221 to get the correct amount of material. M758 S0.095 ; set steps/nL

Typical S values for M758:

Code:

MK-1 ABS 1.75mm .09-.12 EMO-25 Plasticine .06

I know this post is old, but theres any g-code that lower the heat bed all the way to the bottom? Im having issues when a prints is finish and is too close to the extruder, specially on smaller parts. Thanks

Just add in the End G-code something like G1 Z100 or something like that depending on the zheight

Yes sometimes, if I want to change some small parameters, but mostly for setting the heatbed on or off or the extruder temp.