Transom window lithophane

Years ago I ripped the old rusted out duct work from my hallway and thought it would be cool to use the holes that left above the doorways as some sort of stylized window / ventilation path, now that I have my MPCNC I finally have something up there! I started making Fallout themed lithophanes, this one out of 1/8" HDPE.

A vacuum table would have been very useful for this, but getting my hands covered in rice grain looking plastic chips manually holding down the center part that wanted to pop up wasn’t too bad. The HDPE machined really well with the usual 1/8" flat endmill and the occasional squirt of water to keep it cool. I may have given myself cancer by breathing it in but it looks cool so it’s worth it.


Nick, that is very cool! A couple of questions for you. Did you use normal speeds and feeds for the HDPE? Also, did the material melt at all? Planning on doing some cutting very soon with seaboard so I wanted to see what your experiences were like.

Yup, default feed speed of 1016mm/min from jscut, but I think I could have gone up to 1500mm/min because at the deepest I was only cutting 2.5mm. I got a little bit of melting and chips sticking together on the first section, but then I started squirting water into the holes with a large syringe and that kept the bit cool enough so it wasn’t a problem. I don’t remember where I got it, but I have a 70mL plastic syringe I use for topping off the water cooling reservoir on my gaming rig.

Great thank you I will take your suggestions into account!

Love it!