A project log for MultiBot CNC v2

A low cost 3D printed CNC that can be built with minimal tools yet is capable of great things.

David TuckerDavid Tucker 12/02/2021 at 03:430 Comments

Lightburn is one of the most frustrating programs I have ever used.  It is very close to being an excellent program but some odd ideology really holds it back.  I have written previously about my frustrations with it not working with a standard negative CNC coordinate system.  

Now I'm trying to get the rotary axis working and they only let the X axis be the linear axis, while the rotary axis can only be on the Y, Z, and A axis.  And if you add the rotary to the A axis then they insist on the rotary turning exactly 1 degree for ever full unit of travel.

In this case it is going to force me to severally limit how long of an object I can turn on the rotary.  I will probably only be able to handle 6" long objects in this configuration.  If I could use the Y axis for the linear axis then I could use the full 460mm (18") of motion to laser the object, and I could support a piece that is infinitely long, assuming I could find a way to support it across the whole length.

Both of these problems are not technical ones.  Making a transform to let you use negative coordinates or use a Y axis in place of the X is trivial, only a few lines of code.  The problem is the authors dedication to there ideology that there is only one right way to configure a machine.

This is a problem I see all over the place, ideology (rules of thumb that guide us) are used without thought.  I often hear "Buy once, cry once" on forums, but while that is not terrible advice it is far too generic to just apply to your life.  What if your trying out a new tool that you only need to use once, or your budget is very limited, or your not using the tool in a professional capacity. All of these are legitimate reasons to buy the cheaper tool rather than investing upfront in the expensive one.  The world is messy, and while one idea may be the 'only way' on paper, that does not mean we need to be a slave to it.  Sometimes being flexible is much more valuable than being right.