Reprap Host – Gotcha’s

There are a number of “features” in reprap host that make it confusing to use. So much so that most people seem to have given up on it and now recommend either using Skeinforge or Repsnapper.

  • There are a number of “legacy” preferences, that at first look, you would expect can adjust things like the steps/mm however these settings are really edited by modifying the firmware
  • The MaximumFeedRateX and MaximumFeedRateY parameters do effect the feedrate, but only when using the axis jog dials. When printing, or using the Home button (in the same screen as the jog dials!) The firmware settings are used.
  • The Extruder control tab seems to start off with the extruder set to reverse despite the reverse checkbox being un-checked. You have to check and uncheck it to get it to be correct.
  • The feed-rate of the Extruder is constrained by theĀ  Extruder0_FastXYFeedrate setting which would be expected, however its also constrained by the MaximumFeedRateX and MaximumFeedRateY Global preferences. This is quite annoying for me, because I have such a low feed rate (200mm/min) so if I want to use the XYZ jog dials I have to set the preference to 200mm/min, but then if I want to prepare the extruder by loading it up with filament, I have to remember to go and change all the preferences to 3000mm/min
  • By clicking various combinations of the ramp and switch heat on/off button the text on the button can say anyone of the following:
    • Switch heat on
    • Switch heat off
    • Switch heater off
    • Switch heater on

    Also because the ramp button does not properly change the up/down state of the heat button by playing around you can get various confusing combinations of state compared to the text that tells you what the state will be when you press it!

  • The Ramp button is only really needed for drying cement, (i.e. part of the extruder manufacturing process) Its really confusing to have this button on the tab at-all, especially in combination with the above feature.
  • The Layer height preference must be set the same for all extruder’s. If different settings are used for each extruder the software makes a calculation error and starts the print at Z4.0 i.e 4mm above the bed! This one caused me a lot of pain recently as I had no clue as to why the gcodes being generated would be wrong. it was only by chance that I ran reprap from the command line and noticed an error message saying that they were different, and luckily guessed that this was the cause.
  • The documentation suggests that by changing InterLayerCooling to false and setting Extruder0_CoolingPeriod to -1 that the machine will not return to the home position between each layer, however looking through the source code it is apparent, that it is impossible to disable Homing. The software needs to be fixed to achieve this.
  • Finally Reprap host is incredibly slow, its about 10x slower than Skeinforge, and Skeinforge is about 10x slower than Repsnapper, making Reprap host 100x slower than Repsnapper! I should think the reason for this is probably the use of TeMpOrY gcode files rather than using memory mapped files or something else. When I run reprap host, my system usually grinds to an unusably slow rate for 10 mins or so. Repsnapper generates gcode for the same file in a number of seconds.

Finally here is a screenshot of the wonderful Repsnapper (since I had never seen a screenshot before using it)

Welcome to the future.