3D printing with a smaller nozzle diameter

Is it worth to use a smaller nozzle on a 3D printer?

For sure, a smaller nozzle produces finer details,
but how tricky and troublesome it can be !

I changed my hot end after my experiments with cheap nylon trimmer line, and it happened I had a 0.3mm nozzle around. Was it worthwhile for even finer prints?

True, you can/do get finer details... but once again, there are trade-offs. And as for me, I will still mostly use a larger nozzle for the reasons I explain below.

3D printing with cheap Nylon trimmer line/string

Is filament quality so important after all?

I heard a while ago that Trimming line was one of the many materials that was experimented with a 3D printer (precisely in this post), but this time I tried by myself.

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 overshoot 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?

Copyrights and 3D printable objects: a forthcoming war!

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 better answer to the issue than what the music majors had, or they will just fail anyway.

Will all the printer owners become the next pirates?

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 ?

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 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.

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 house and even their own leg!

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.

But as I write this post (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 would be a very frustrating experience because it is just not reliable enough for the average user. It is even quite hard to reach an acceptable quality even for people born with a screwdriver in their hand. Please read on!

Which hobbed bolt for a filament feeder? My home made one!

Driving the filament with hobbed / knurled bolts

My quite efficient hobbed bolt :)

As all owners of 3D printers know, one item of utmost importance is the so-called "hobbed bolt", "knurled bolt" or "driving shaft". It is one necessary "vitamin" (ie. non-printable) item that is coupled to a motor and which rotation drives the filament into the hot end (check the whole setup).

Now, molten plastic still does not flow easily through our tiny nozzles (~0.4mm), and the force to be applied is quite high. Pushing the filament manually gives a good idea, as one hand is barely enough. Since a nice value is about 15 to 20 Kg of traction, this is were problems start to arise given the small filament diameters used by 3D printers (3mm or even 1.75mm).

How to run a (Cura) Python plugin on STL files without Cura?

Here is a geekier post about how to tweak Cura plugins and convert them to standalone Python scripts that post-process your g-code without Cura nor Skeinforge.

After I designed and used my wood gradient plugin, people naturally started to ask for the source code. I was a bit lazy first, because it was made for Cura 12.08: the patch I released was not very convenient, and Cura had evolved with a better and simpler plugin system, including my plugin.

Now, I got the time to fix it. Here is how I converted it to a standalone Python script that runs on its own, asking nothing to nobody.

Molding and casting with a 3D printer

Printing a mold and/or lost wax casting

Or how 3D printer also opens the way to semi-industrial homemade objects beyond artistic sculptures!

Indeed, a 3D printer can be used indirectly, to print a mold of the object and not the object itself. The printed object is used as a "shape", and the final object is made of something else that could not be printed directly such as aluminum or silicone.

Molding is also useful to produce small batches of objects (even out of plastic), in a way which is much quicker than by 3D-printing them. 3D printers still are only rapid prototyping machines not ready for mass production.

Ron Thompson explains very nicely how he made his aluminum heating block for his gravity filament extruder:
here is a two-part oil-bonded sand mold, rammed around 3D-printed orange plastic shapes.

How fine can an Ultimaker print?

Ultimaker impressive quality at 0.075 mm layer height

I printed one famous treefrog on my Ultimaker for a friend and realized I forgot to speak so far about the overall quality you can reach with an Ultimaker.

It gets hard to feel the layers by sliding your nail. The most prominent place where layers show up is between the eyes.
This print is not postprocessed (see the hair-like filaments not yet removed/sanded/burnt ?)

Review: what materials can be 3D printed?

Mixed wood and bioplastic (PLA)

What materials to 3D-print ?

Every once a while I'm being asked about it, so here is a post on the many materials that can be 3D-printed at home.

It is not complete and will expand with time. It is no buyer's guide either, nor a technical document. Read it as a short generic survey of usable materials.

As for me and many others, I print mostly with PLA filament. Even though I have a set of other materials (wood, rubber, nylon etc), I did not test all the following myself, mostly because each material requires its set of specific time-consuming trials and errors to achieve good quality. Mastering all of them would take me months, if not years!