Archive for December 20th, 2017
GCMC includes single-stroke fonts derived from Hershey fonts, so I added a legend to the Spirograph Shakedown generator:
Obviously, plotting 2.5 mm tall characters at 3000 mm/min = 50 mm/s isn’t a Good Idea on a less-than-absolutely-rigid CNC machine.
Slowing down to 250 mm/min = 4.2 mm/s produces much better results:
A closer look, albeit with less-than-crisp focus:
This isn’t a conclusive test, but it reminds me that Speed Kills.
The green plotter pen started life with a standard 0.3 mm felt nib, but it’s worn somewhat wider over the intervening
years decades. Those 2.5 mm characters would look better coming from a narrow ceramic pen, which would require a pen change before doing the legend; using 4 mm characters would produce better results.
The line spacing is 110% of the font X height, which obviously isn’t quite enough. Something on the order of 150% should look better.
This GCMC code (including those mods) produces the legend:
feedrate(250mm); textsize = [4.0mm,4.0mm]; textat = [0.5*PlotSize.x/2,-PlotSize.y/2 + 2*textsize.y]; textpath = typeset("Seed: " + PRNG_Seed + " Stator: " + StatorTeeth + " Rotor: " + RotorTeeth,FONT_HSANS_1); scalepath = scale(textpath,textsize); placepath = scalepath + textat; engrave(placepath,1.0mm,-1.0mm); textpath = typeset("Offset: " + L + " Lobes: " + Lobes + " Turns: " + Turns,FONT_HSANS_1); scalepath = scale(textpath,textsize); placepath = scalepath + textat + [-,-1.5*textsize.y]; engrave(placepath,1.0mm,-1.0mm);