Some simple designs out of melted plastic

Dusted of MPCNC again for the first time in about 12 months - as have been busy 3d printing in the meantime.

Used ‘Teaching Tech’ YouTube method of creating flat plastic sheets out of 3d printer waste to create a few very colourful flat plastic sheets - around 15 inches square and 3 - 5mm thick.

Made out of purge waste and melted (some of them fairly big) waste and failed prints - see this thread for background info on the melting process if you are interested. Making better use of Flush-into object in Bambu Studio - #51 by Ukdavewood - Bambu Lab AMS - Bambu Lab Community Forum

Quite pleased with the results - and as the parts are made out of melted plastic - the off cuts or any failed cuts can be remelted again back into full sheets for further cutting.

Also used cnc.js for the first time - using the ‘shop floor tablet interface’. - quite pleased with a little add-on I made - using javascript bookmarklets to populate the MDI fields with the GCODE I like to use - such as Home X Y and reset X Y Z - Quite simple javascript which needs to be URL encoded this with commented parts re - applied
var bm_title = “Home X Y”;
var f = document.getElementById(“mditext0”);
f.value = "G28 X Y " + String.fromCharCode(59) + bm_title;


That’s actually a really cool idea and if you play your cards right you could make some really cools signs or even inlays out of the plastic


This is really a great idea, thanks. :slightly_smiling_face:


The google term and subsequent rabbit hole you are looking for is “precious plastic” :smiley:

And they look super!

@ukdavewood if you are going to machine more plastic, this Knowledge Base might be worth your interest :slight_smile: There are a lot of tips around machining, sawing, forming, bending, etc. plastics.



Two gratuitous mentions of LowRider CNC in this video by Teaching Tech! Time indexes in these links should be just before the mentions…


Cool idea. I certainly have enough pla scraps…as we all do I guess.

Something slightly more complex out of melted sheets,

Temporary AMS stacker – for print head access.

I can smell that the plastic is melting, plus a fair number of the chips gather in the cuts partly due to melting, but the cuts clear out quite nicely once the cut goes fully through. It’s actually quite nice cutting the plastic vs wood - due to lack of mess.

I’ve been using an MPCNC Burley with around 1m x 1m build volume, cuts are using a 5mm single spline, straight cut bit, with feed rate 1500mm/s, cut depth 1mm increments, tabs almost the whole depth, the Katsu router is on setting 2.5/6 – so I am guessing around 20000rpm

Have refined using of CNC.js - set up some little GCODE files in the watch folder, uploaded using octoprint - one for homing for example (M17,G28 X Y, M114), which seems to work quite well - as it seems to need some sort of job to run to jump into action. Then I manually adjust the Z height, reset the coordinates (using G29 Z0 (plus X0 Y0 if appropriate) bookmarklet) and then load the correct cutting gcode files and run them.