Tuesday, March 15, 2011


So, where was I... I got through all the PLA tests I wanted to do, and actually used a whole pound of Black PLA. In the end I printed a full Prusa Mendel, and better quality than most of the parts on my printer... I've posted those Black PLA parts to eBay, since I still don't have all the electronics yet for a second printer.  I decided in the course of my Prusa upgrades and switching to PLA that it's probably best to have two extruders for each printer.  I don't mean a two headed printer, but and extra extruder sitting by in case something goes wrong.  Then I can just swap in the second one and make repairs on the first.  PLA Doesn't jam as much as I was led to believe, maybe older designs did, but Wade's extruder design works great.  When PLA does jam, which it did on my old extruder, it... takes a while to fix... days.  I did have more blobbing and lots, and lots of strings from PLA, it makes a thread like filament when the extruder moves.  By the end of printing the Black Prusa I had the extrusion reversing far enough and quick enough that it mostly wasn't an issue (15mm at 100mm/s).  I think I've gotten as good with printing as I can without more exact measuring devices.  I'd like to try using a small digital scale to compare the grams output in Skeinforge to the actual weight of printed objects, and a caliper to get some measurements on plastic output vs. input. 

With the all PLA X-Carriage on... my unnamed... repstrap-converted-to-prusa... I still have one white ABS part, the 11 tooth extruder gear w/ set screw (that I glued in place instead of using the set screw).  This part is going to have to be replaced soonish, the less flexible PLA 39 tooth gear is digging into the smaller, softer ABS gear, slowly creating a fine abs powder out of it.  For now they mesh great, and mesh greater with use, but I have to assume eventually one gear will destroy the other. Fortunately they have prime numbers of teeth so it will wear evenly.

What else... FreeBSD was fun, but not something that will work for me long term. Then I tried GNU/Hurd for a couple days in Virtualbox... not ready for prime-time... SOoo now I'm trying out Arch Linux in Virtualbox. We'll see how it goes.

Oh and I bought the Domain name reprapatopolis.com yesterday for this blog. I'd like the next reprap I print will be big enough to print a chair, made of gray PLA and ABS, I'll call it "the Reprapatopolis Hippopotamus".
Best idea EVER.


  1. Have you lubricated the gears? I found with ABS on ABS the small gear wore out quickly until Wade advised me to put lithium grease on the gears. Now they last for many months.

  2. I hadn't tried that, I'd hadn't really considered it for some reason... Thanks.