Print a CNC Mill

Watching a “Tom’s” video I was made aware of the Mostly Printed Parts CNC mill  that is made with 3/4″ electrical conduit.

Printing Parts

This job is 90 plus hours of printing!  The Prusa MK3 is pumping out prints but not all has gone well.  The printer formally known as an ANet A8 was taken out of service due to equipment failure…. so, I fired up the FLSun Cube.

FLSun Cube

The FLSun Cube kit had several problems and their support response was very slow despite appearing to be reasonable.  I’ve had the printer for a couple of months but only recently received replacement parts and finished the build.  I hadn’t printed with it.   To start, there are no information on settings for Slic3r or Cura.  I have some pretty rugged looking prints from figuring out the right settings.  In the end I am using Slic3r that came with my Prusa so I don’t have to work with different slicers for different machines.

In the end I dialed in PETG and PC on the Cube and at least some of the parts printed will be used in this CNC build.

Material Types

Having seemly dialed it in with Polycarbonate  I was having warping issues so I switched to PETG.  With a little Z-Hop on retraction, and what I would consider a large amount of retraction, and tweaking temperature I found PETG printed nicely.  Even without part cooling the stringing wasn’t too bad.  I found finding the right temperature critical to a clean print.  Too low and there are a lot of balls and rips, too hot there is sagging.  When it is too cold the balls and rips are collected on the hot-end and end up catching and stringing on travel movements.

Dialed in the PETG prints are close to the same quality as my Prusa MK3.  With a parts cooling fan it would probably be the same quality.  So being picky paid off.  I made sure the motion was smooth (thus the problem parts) before I fired it up.  Even as a basic stock printer (other than I did replace the fans ) I cannot complain about the prints.  However, bed leveling isn’t auto.  I print 4 loops on a skirt and 6mm of brim.  That way I can level the bed during the skirt and brim based on what I am seeing and don’t end up restarting to change the Z offset. I can only assume the probe readings change with temperature.


In the past I’ve had really good luck with PC and I ordered several spools from China that I decided would be the best choice for this job.  PC is harder, stronger, and more heat resistant than PETG but as I am discovering it can be tricky to work with.  I will try drying the filament and see if that helps.  When I first opened it, it would stick hard but now I have to really have it dialed in to get it to stick.  In the past I was having trouble with a spool of PC until I tested my dryer and then it started sticking again.  Hopefully that is all I am looking.  There is a lot to learn and for now I have two printers running that are teaching me a lot.  Hopefully I can come up with material management techniques that will address this issue with PC as I really like how it prints.


It took a week of printing.  It seems there is more than 90 hours of printing but I did reprint many of the parts.  At least the FLSun Cube is working and producing usable parts.   The MK3 prints are superior but the Cube prints are not bad.

For $135 you can buy the printed parts.  Considering the cost for the filament that is only about $100.  For $100 you can save yourself 100 hours of printing.

OK, I actually wanted to do the printing.  I want the printing experience!  A couple of more reasons to print your own, being able to select colors and materials.  After doing all the printing I have to say the online pre-printed parts kit is a  good deal.

And then for $286 plus shipping you can buy the hardware and electronics kit.    I spent $275 (which included shipping) purchasing the parts piece by piece.  The main difference is that I went with a controller I am familiar with and ended up with enough spare hardware to pretty much build another unit. Still, there isn’t much difference in cost unless I actually build a second one.

Before you follow my lead and start ordering and printing parts consider what the the original author is offering. I know at after 60 hours of printing and was looking at the really big parts still ahead of me I cringed.   He has a great site and you really cannot beat the deal being offered. For most people I’d recommend buying directly from the author. His site offers all the details.


Author: Marc

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