For printing the MK4/MK3.9 printable parts on a Prusa XL

There are no changes to the models; the only purpose of this remix is to provide project and code files when printing on a Prusa XL instead on the original i3MKS+.

I needed this and I'm thinking that it can be useful to others.

Also, I'm showing where to find the revision number on the xLCD board; this is missing in the manual. The project and code corresponding to the xLCD cover is for boards having a revision 28 or higher.

Changelog:

• July 21st, 2024
  • Initial version
• August 15th, 2024
  • the y-rod-holder-r2 is too flimsy when sliced using the Arachne perimeter generator; nominally it should detect to thin walls but in the 2.8 version it doesn't work; therefore I choose to provide a separate project and g-code for printing the four instance of the y-rode-holder-r2. You can also change the perimeter generator in the 1_mk4_mk39_upgrade_blk project file and generate the g-code. I added a side by side image of the print results: on the left with the default Arachne perimeter generator and on the right with the Classic perimeter generator. However, I think that this piece should be redesigned by Prusa to reinforce the upper arch.

Finally, I provide a Bill of Materials which helps to devise what are the parts and how many instances are needed. This information can be also gathered from the project files.

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 qty  part                              color   batch  structure             
─────────────────────────────────────────────────────────────────────────
   1  y-belt-idler-r2                   black       1  Frame                 
   1  y-motor-holder-r3                 black       1  Frame                 
   4  y-rod-holder-r2                   black       1  Y-carriage&Heath
   1  y-belt-holder-R2                  black       1  Y-carriage&Heath
   1  y-belt-tensioner-r2               black       1  Y-carriage&Heath
─────────────────────────────────────────────────────────────────────────
   1  x-cariage-r2                      black       2  X-axis & carriage  
   1  x-carriage-clip-r2                black       2  X-axis & carriage
   1  x-carriage-back-r2                black       2  Z-axis                
   1  x-carriage-cable-holder           black       2  Z-axis                
   1  x-carriage-cable-holder-cover-r2  black       2  Z-axis                
─────────────────────────────────────────────────────────────────────────
   1  xlcd-knob-r2                      black       3  xLCD                  
   1  xlcd-cover-r3                     black       3  xLCD                  
   1  xlcd-support-left-r4              black       3  xLCD                  
   1  xlcd-support-right-r4             black       3  xLCD                  
─────────────────────────────────────────────────────────────────────────
   1  fan-door-r2                       black       4  Nextruder             
   0  fan-shroud-r2                     black       0  Nextruder             
   1  pg-assembly-adapter-mk4-r1        black       4  Nextruder             
   1  pg-case-r3                        black       4  Nextruder             
   2  idker-swivel-r2                   black       4  Nextruder             
   1  idler-nut-r2                      black       4  Nextruder             
   1  liveboard-cover-r2                black       4  Nextruder             
   1  liveboard-cover-right-r2          black       4  Nextruder             
   1  main-plate-r2                     black       4  NExtruder             
   1  ideler-lever-a-r2                 black       4  Nextruder             
   1  ideler-lever-b-r2                 black       4  Nextruder             
─────────────────────────────────────────────────────────────────────────
   1  el-box-cover-r3                   black       5  Y-carriage&Heath
   1  wifi-cover-r2                     black       5  Y-carriage&Heath
   1  heatbed-cable-cover-top-r2        black       5  Y-carriage&Heath
   1  heatbed-cable-cover-bottom-r2     black       5  Y-carriage&Heath
   1  heatbed-cable-holder-r2           black       5  Y-carriage&Heath
   1  ext-cable-holder-a-r2             black       5  Z-axis                
   1  ext-cable-holder-b-r2             black       5  Z-axis                
─────────────────────────────────────────────────────────────────────────
   1  filament-guide-r2                 black       6  Y-carriage&Heath
─────────────────────────────────────────────────────────────────────────
   1  x-end-motor-r2                    orange      7  X-axis & carriage   
   1  x-end-idler-r2                    orange      7  X-axis & carriage   
   2  x-end-clip-r2                     orange      7  X-axis & carriage 
   1  z-bottom-left-r2                  orange      7  Z-axis                
   1  z-bottom-right-r2                 orange      7  Z-axis                
   1  z-top-right-r3                    orange      7  Z-axis                
   1  z-top-left-r3                     orange      7  Z-axis                
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