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Some links about me. Many of my 3D designs are free. I also post on Google+ and in another blog, oz4.us
review (32) general (26) issue (16) mechanical (16) replacement (14) software (13) addon (12) bowden tube (10) business (10) consumables (10) heat (10) feeder (8) hot end (8) weird (7) motor (6) off-topic (6) trick (6) electric (4) bed (3) cnc (2)

Saturday, April 27, 2013

3D printing with cheap Nylon trimmer line/string

Is filament quality so important after all?

I heard years ago that trimming line was one of the many materials that was tested on a 3D printer (the biggest list is probably here). This time I tried for myself, and it was also the proper occasion to deal with how "reliable" the material has to be (note that I wrote another post more specifically on how to print it).

Really, trimmer line may be a fully compatible filament !
My hot end is dying: the annoying PEEK thermal insulator started to melt (I suspect that the PID regulator overshot the temperature because of intermittent connection that I have fixed since). Still, it does not impede the flow much, so it gave me the opportunity to try some risky fun : what about this basic nylon trimmer line I got for free 10+ years ago when I purchased my gardening trimmer tool?

Wednesday, April 17, 2013

Copyrights and 3D printing: a forthcoming war bigger than that of the MP3 music

So, what about copyrights?

Free and customizable GoPro-compatible mounts:
not illegal because I designed them! Still, would GoPro
appreciate it when they would charge $30+ for this?
It is no secret by the early adopters that 3D printing at home will soon become one major copyright battle. And I sincerely hope the industry will find a better answer than that of the music majors regarding mp3 music, or they will just fail anyway.

Will all the printer owners become the next pirates? And reciprocally, will the big player violate our own creative commons copyrights (or impede innovation at the hobbyist level with they own broad patents, see my longer post on the subject)?

Is there a chance that we soon get commercial repositories where we can buy, download, customize, and print Lego bricks, Barbie dolls and cheap vehicle spare parts? Or will it be the hard way with inefficient injunctions, DMCA and court battles again ?

Friday, April 12, 2013

Rollerstruder: a filament feeder / driver / extruder

The rollerstruder filament drive system on an Ultimaker
Almost one year ago I got rid of the plywood Ultimaker filament drive mechanism. It is an extremely important part of the FDM process as it pushes the (cold) filament towards the (hot) end. Any malfunction at this stage systematically leads to a bad print. So when not reliable, you have to stay close and react quickly to fix troubles, for example by feeding the filament further manually (btw check this if you are still doing it on an Ultimaker).

As for me, most of the trouble came from the old bolt that was shipped with my printer: it was grinding my filaments a lot, sometimes to the point it would stop moving completely and ruin the hour-long printable kalashnikov. It also lacked Bertho's addition of a ball bearing on the "idler arm", which soon became part of the official design.

In fact I just don't know about the new official drive mechanism (which seems way more reliable given the forum feedback), because I designed my own feeder that has to match my more efficient but unsual hobbed bolt. It suits me completely: months of intensive usage without a failure. And I learnt a lot of openscad and industrial design by the way.

Wednesday, April 10, 2013

What cannot be 3D printed? Time to debunk some myths!

General 3D printing misinformation: review of facts and fiction!

Each technology has some fundamental limitations, and 3D printing is no exception.

As soon as I owned and wrote about 3D printers, people started "spamming" me with mainstream articles about it (no pun: still I like them and still I learn from them!). So even our grandparents would soon be printing their glasses, their bikes, their firearms, their houses and even their own legs!

For sure, I am not the one that will disenchant this emerging technology: I am writing this blog and I regularly post new designs on Thingiverse repository.

But as I write this (april 2013), you just cannot buy a 3D printer and print anything, nor even expect it to work as advertised if you do not understand very clearly how the thing works. It is just not reliable enough for the average user (unless you have no special expectation, in which case this pay doh printer may avoid frustrating experiences). It is even quite hard to reach an acceptable quality even for people born with a screwdriver in their hand.
Update 2021 : we're closer to reliable, out-of-the-box 3D printers. Still they often need to be properly tuned, especially the low-cost ones. And time will not fix their other drawbacks. Please read on!