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Some links about me. Many of my 3D designs are free. I also post on Google+

Saturday, May 16, 2015

Messy code, branches with a lack of guidelines and comments are killimg Marlin!

Marlin no more exists as a single, readable, common branch!

Where shall I go now?

In a previous post, I described a tiny contribution I made to the 3D printer firmware Marlin. The deal was to help with the calibration of a Delta printer thanks to a manual Z-probe (calibration really is the drawback of Delta printers, due to their weird geometry as compared to easier cartesian X-Y bots like the usual printers). It was already painful for such a small, one-time improvement to the code source, and given the invested time, I tried to make it broader by implementing multi-line comments (and to learn about git by the way).

This is how I feel when I want to code something in Marlin!
(Malcom in the Middle, fixing a light bulb)

So I worked in mainstream Marlin. My idea was that it could benefit to existing variants of Marlin as well, when they decide to get changes from the "official" parent. But it does not work so well in reality.

This experience unveiled another, deeper, issue related to the many Marlin variants, and I think it is due to the fundamental way github works, in addition to git own complexity. In my opinion, Marlin is just dying because of this, together with the limits of the Arduino platform.


Tuesday, April 21, 2015

Headlines again... 3D printing guns, a passion?

Headlines again: 3D printing yet another part of a gun. So what?

Please Cody, yes, you the guy with big stainless-steel thermoplastic bollocks, please, now I want new stuff, like 3D printing bazookas, ammo or landmines!

I already tackled the subject it in this older post but telling that a 3D printer is probably not the best tool to use is not even my point here. Using a 3D printer to print more guns is no surprise, but I wish headlines focus more on noble usage like e-NABLE prosthetics. It is an excellent project, where volunteers 3D print free upper-limb prosthetics, like artificial hands for others. If your printer is idle, you should go and read about them!
E-NABLE: is this not a better use for 3D printing, according to you?
This way we have people printing tools that may harm people, while other people do repair them. Nice absurd world.

Here is my point for once: why do the words gun and freedom have to be put in the same sentence almost each time pro-gunners start to argue? What the heck?

Sunday, April 5, 2015

3D printer survival kit: a comprehensive set of 3D printer tools and tips.


Survival kit: tools for the 3D printers


This post started as early as September 2013, and it eventually ends here, may 2015! At least, you can be sure I heavily made my opinion and I have feedback on the tools I list here.

All included, a nicely packed Ultimaker 100% ready for travel.
I keep nearly all my tools in a dedicated box, that matches well the bottom of my printer. You will read in this post about each of the tools, slightly sorted in different categories and even though some tools are used for multiple tasks.

I attached a note after each of the items, where 5/5 is a must in my opinion, and 0/5 a luxury or a useless tools. Of course there are no 0/5 in my box as I want only a (comfortable) survival kit in the end. Read more...


Monday, March 30, 2015

CNC fail? 3D printed design blows my ears instead of the dust

I bought a well-built Chinese CNC machine last year, namely a 4 axis CNC3040Z-DQ router/engraver, for about €1000 (as far as I remember).

Milling a PCB with a low cost CNC router/engraver controlled by LinuxCNC.
My initial need was to "etch" electronics PCB boards at home, to get rid of so called proto- and perf boards. This machine is overkill for the job, but I do not regret my purchase since it can do much more than PCB milling...

But only recently did I spend enough time to use it. Even though the reliability and consistency of a CNC milling machine is way better than that of a 3D printer, the whole process is cumbersome. It takes a lot of time to get used to the software, which is a decade behind the ergonomics of more intuitive 3D printing software. Worst, the controlling software like linuxCNC or Mach3 still require a parallel port and a special real-time distribution of linux. Both are a real pain because you need a dedicated and obsolete machine just to drive the CNC. Recent projects like GRBL are knocking at the door though, as an alternative to parallel port hardware: they rely on Arduinos, but are limited by the power of this platform. ARM-based boards are more promising, especially for fast machines, or when you have more than 3 axis of freedom (e.g. see 6DoF)

Note: I may write more about CNC machining at home, its software and process in other posts. But I start here with a quick, funny, and miserable failure of mine, that was meant to be an improvement in the first place. And, well, it mixes printing and milling so it is a good transition.


Tuesday, January 27, 2015

Contributing to projects hosted on github: a step by step howto, and an illustration with Marlin (3D printer firmware).

Git is powerful... and very painful the first time! / Github contribution howto / Tweaking Marlin for better 3D printer menus.

Git mess, only partially resumed by Oliver Steele.
Indeed, the upstream higher repository is not shown here,
as seen on this other bigger, clean and useful cheat sheet.
I eventually wrote a feature to fix something that annoyed me for years: allow multi-line commands in the LCD menus of Marlin, a very well known firmware for 3D printer.

I needed it for my Delta printer: these printer do require precise calibration, often with a sequence of gcode commands (check the end of this post for more and why I wanted these to be in my menus and not as initialization files on all my SD cards nor on a PC over a USB cable).

Now, Marlin is hosted on github, a community front end to many other open source projects. Actually, the linux kernel itself is developed with git so it works, for sure.

I often tried to use github, but I never went past a simple git clone of a repository. It was still better than to download a zip archive, because you can easily get the new stuff with a git pull. But here and partially out of curiosity, I wanted to try and contribute to a project at the source.

Now... what a huge and painful procedure just to give a hand! Seriously, it is mind boggling how much crap and megabytes need to be handled just to help and submit a few dozen f*king lines of code to an opensource project hosted on github. This is too bad since I am sure many programmers would be glad to give a hand to project they stumble upon (like me, often), but without this need to become administrators of complex and shared projects themselves!

This article is all about posting and contributing to a project hosted on github. You'll get the calibration g-code line I used at the end of the post if you really ask yourself.

Thursday, January 8, 2015

Sad day for intelligence and respect.



David Pope
I can't even blame those stupid murderers at Charlie Hebdo. They just are not worth the intelligence nature gives us. If at least it was for money or power, there would be some sort of "justification". But no, this is the most profound proof that some individual are able to deny their own free will, curiosity and intelligence to some obscure ideology. Why on earth would someone who is saying or drawing something would do with your very own religion? Faith has no proof and need no proof. Faith without respect is blind stupidity.

And let me be clear, now every racist will exult with this opportunity to prove they are not better at trying to live in peace altogether.

Sunday, November 23, 2014

How to use Openscad (4): children and advanced topics

Part 4/5: children, factorized placement and chained hulls

Yes, it was made with Openscad and it is parametric!
(extreme collaborative work, picture by N.Goodger)
Previously in this tutorial for the Openscad CAD software, we talked only about modules that behaved as shapes.


A powerful and often ignored feature of Openscad is that modules can also behave as if they were operators, exactly like the translate()or color() operators. They do not create shapes on their own, but they modify the subsequent commands.

In Openscad, it is possible through the use of children. But first, let us create and discuss a bit about a common-case example.



Saturday, November 22, 2014

How to use Openscad (3): iterations, extrusions and more modularity!

Part 3/5: iteration, extrusion and useful parametrized CSG techniques

Repeating shapes

As we saw in the previous article, repeating a shape by copy/pasting its Openscad definition is a bad practice. It increases the risk of mistakes just because of the slight changes that have to be made on each of the copies. And any "regularity" should be factorized: let the computer do our work!


The former way we built a (partially) rounded cube. Four copy/pastes? Boo!

See how the four columns really are all the same cylinder, where only the position changes? This is where we can and we should use loops instead. And once again there are different ways to do so.


Thursday, November 6, 2014

Fortune 500 teller? 3D printing trends, reports, analyses and business intelligence...

Are the "high-level strategically analyzed reports" worth something?

Hey, could my blog be so informative? :)

I am regularly contacted, mostly on linkedIn, by experts that seek data. The last time it was for a company that compiles data and trends "for the Fortune 500 companies". Which does not excite me more than that, and here is why.

Such data are usually sold at an incredible price to managers that think they would get a better clue at the market, with the idea that they would be more profitable. But there are two traps here.

The first one is: am I really enough of an expert to give clues to Fortune 500 companies? I am mostly an iconoclast, e.g. when I say not to invest in Makerbot at all (neither as a customer nor as an investor, but I have a full-length analysis why I say so), or when I explain why, imho, "pro/expensive" FDM printers are almost a scam nowadays. OK, I may be better than a monkey and provide a few useful reviews (e.g. materials for artists, or what cannot be 3D printed...). But still, asking my opinion on the market trends could cast a doubt on the forthcoming corresponding report. Oh, well, may be they also want data from makers -- why not after all.

As a manager, do you really need accurate trends and data?
Or do you need only the feeling that you have some?
Secondly and as importantly, the reviews are most often never used in reality. Once bought, they are dropped on the desk of a subordinate in the company, with the advice to get some insight from the document. The underlying idea is: since it is expensive it must be valuable...

Thursday, September 11, 2014

How to use Openscad (2): variables and modules for parametric designs

Part 2/5: Variable and parametric design

The previous part addressed the basics of Openscad. It relied mostly on "immediate values": we were providing dimensions as explicit numbers. If you want to tweak the design dimensions, then you need to parse the scad source code and fix the numbers all everywhere.

In fact "hard coded" numbers must be avoided. As opposed to "static" designs, parametric designs give the flexibility to tune the numbers very efficiently at one place only. The good point is that Openscad is one of the best tool to do so.

A larger mug by using the scale operator (from the "basic" tutorial).
This is still not parametric, as numbers are hard-coded (a bad practice).
See how the numbers in our mug design above depends on each other? If the cube is to be made taller for any reason, then the intersecting sphere and hollow cylinder must be tuned accordingly in the source code. And this is exactly something a computer can do better than us.

So let us first convert this design to a parametric version, i.e. a design that can be tweaked with a small set of parameters that all have a clear role (width, height and so).


How to use Openscad (1), tricks and tips to design a parametric 3D object

Part 1/5: Introduction to constructive solid geometry with Openscad

Some technical and non-technical people keep asking me how I create new designs. As often, after a few personal replies, I end up heading to the blog to share the answer as they keep asking for more.

Also I long wanted to write a pragmatic and step-by-step introduction to Openscad. The idea is to help people even with no programming skills (mostly in this part) and to bring newcomers to a point that they can design their own 3D objects (part two).
If only a few readers switch to "designers" by reading this I will be quite happy. Meanwhile I will have given a detailed answer to my friends and contacts!

A non-obvious GoPro mount of mine, that is fully customizable thanks to Openscad.
It looks complex, but it is still exclusively made of spheres, cylinders and cubes with a few basic "joints".
A forthcoming last part will deal with the complex features of Openscad. This one is for people that either learn fast or for those that are already proficient with the usual features of Openscad.

So first, what is Openscad? Within the CAD family, it is a 3D modeler: a software that helps you to create 3D objects. There are many such tools, but this one is used extensively in the 3D printing community, not only because it is free but because is it really efficient for some kind of objects.

It may or may not suit your mind, but with time I am able to "see" the shape I describe, not as text but directly as shapes. I guess it depends on people, but I am sure there are people that are not programmers that can think alike. And if you are already a programmer with no industrial goal then you really should give it a try. It will be a breeze to use up to a productive level, especially if you do not want to invest time in a new and hellish interactive user interface!

The official manual is OK but it does not really work as an introduction. The navigation is also sometimes difficult to the point goggle is more useful. There is a nice raw cheat sheet also but it has no link to the respective functions (what a pity!) (update: it does now!). In any case these fail to help learning Openscad quickly in my humble opinion.


Thursday, August 14, 2014

Home made filament drying box

How to make a simple dehydrator (drying box) with a solar vacuum tube

A short and probably overkill post for a passive and zero carbon footprint drying box (not counting the required one to make the tube).

I use a spare, high tech and powerful vacuum solar tube, but it is easy to make something with a copper or steel tube painted in black, around which you slide larger transparent plastic bottles. Such insulation is required to avoid the ambient air temperature from cooling your own heated air.

The second required item is a brand used low-tech cardboard box.


Sunday, August 10, 2014

E3D v6 hot end: ideas and assembly tricks

Assembled E3D v6 with a few particularities
You may remember that I wrote broadly about hot ends in an another post, but this short new one is specifically about the sixth revision of the E3D family (E3Dv6).

This is probably the best hot end on the market right now (in my opinion -- and I did not check them all). It is not cheap, hence expensive as all the good quality hot ends. But this is a critical part where you cannot really lose money if you value your time...

However there are still some room for some improvements. 







Sunday, July 6, 2014

Material for artists: 3D printing wood, chalk, and eventually metal with bronze


A gorgeous dual material and well
polished bronze ring by foehnsturm

Important materials for artists


Still today, the visual quality of 3D printed objects is far from perfect. Of course, a stringy or bumpy surface does not mean the part will not work: you can get a visibly ugly part that still works well enough as a mechanical connector for example. But an artist will certainly not like it.

This post tries to list the main filaments that artists would look for first. Many other filaments are listed in a former post about materials that can be printed (without artistic consideration).

It also talks about the brand new bronzeFill filament from ColorFabb. Yes it does contain bronze. No, we are not yet printing metal really. But certainly it is a major and very welcome addition to the list of interesting materials to 3D print.






Friday, June 27, 2014

Four in the morning. Just had a few tweaks to finish my upgrade...

Eventually "implemented" my upgrade! I certainly did not think it would take me so long, but once you start to sort the mess that's below a 3D printer you just can spend days on it! There is a brief list after the break.


I am sure a lot of 3D printer owners share the "two minutes into two hours" syndrome.

Monday, June 2, 2014

Why you should not buy Makerbot 3D printers!

Avoid Makerbot and its 3D printers, they are both wrong.

Really! And there are many reasons not to buy: cost, reliability, human values, innovation and so.

I endorse even less Makerbot business
than I already trusted their products !
But enough is enough, this time I say why.
Seriously, Makerbot Industries care more about money than 3D printers. They so badly want your money that they start using dirty business practices. As a client, their overall strategy is simple: you will increasingly pay more to get less. The quality of the product does not count as long as they keep selling it through marketing tricks. Update: eventually, well-known resellers of 3D printers like imakr even stopped selling them because of after sale burden and heavy customer negative feedback.

Do not think this is a biased joke, neither only a maker's rant (as formerly). I really want to warn would-be customers that they should not buy. And I want to try and stay objective.

But beside this, Makerbot brutal business strategy makes all this clear beyond doubt. I cannot think of any other motive than greed, or may be also for the inflating ego of Bre Pettis, its director. By the way, 3D printing certainly never was invented by Makerbot -- this is pure usurpation. Please do not fall in the trap of old and dirty business practices.


Tuesday, May 20, 2014

The businessman and the maker

The Businessman and the Maker

Businessman v.s. Maker (although Dilbert is certainly not a maker!)
At Fabcon 2014 3D print fair (my feedback is here), I gave a speech entitled "Make it yourself: it can be better than what the industry sells you!".

It was insipred by this former post on the same vein, which rang a bell in Florian Horsh head (so much he very kindly invited me).




3D print fair at Fabcon 2014: feelings and people

Fabcon 2014 - was worth 2575 kilometers and 31 hours on a motorbike!

So I was kindly offered to give the closing talk of the 2014 edition of Fabcon 3.D in Erfurt, Germany.

My talk is now available online as slides, and also as a youtube video (for some unknown reason I cannot embed it here).

Note that I added a short separate post that resumes it, with a few new ideas: The businessman and the maker. This one is about the people and projects I met there.

My spoken English should definitely be improved (and I was half sick half exhausted), but it will spare you pushes on the space bar for the next slide, and more importantly, you still get details in the 25 minutes not-so-lively speech. My apologies, as it was the first time I spoke in public for years (back to my time at the long-gone Palm company, and more significantly during my PhD, huh, 14 year ago!). Please read ahead.

Tuesday, March 25, 2014

Quick comparison: pro versus low cost FDM 3D printers

Are so-called "professional" entry-level 3D FDM printers worth their price?


A LinkedIn user in my network asked for more data when I said that "low cost" FDM printers could compare favorably to "professional" (and expensive) printers. Sure, it is a bold statement, and it does not hold for every of the many "levels of quality", as there are just too numerous. But let me get into more details.
In my opinion, an Ultimaker rev. 2 (~2K€) compares very nicely to a Stratasys UPrint-Se (~23K€)
I certainly do not want to say the "pro" printers are crappy, nor that any brand is crappier than the other, but I had the chance to compare my Ultimaker prints with a "professional" Stratasys entry-level printer (i.e. 1200€ versus 23K€). The outcome is that I just would never swap the two even if I was offered the "pro" one for free! Huh.

Now I am a power tinkerer, I know how to print, I prototype the printer itself, and I cherish freedom, but I tried to keep this bias out of the following arguments.

Thursday, March 20, 2014

Thoughts and hints around hot ends

This post finally documents ideas and hints I had during the design of two hot ends I made last year.
My extremely small "cheesy hot end" (all-metal and actively-cooled), here with an Ultimaker printed support.
This hot end was very easy to make (only used basic tools) and also because the barrel is quite short.
At the time I already had ordered an E3D hot end, but the lead time was so big that I decided to give it try myself. Actually, since I attached it with this tiny E3D support on my Ultimaker, I almost never swapped my hot ends anymore because it is just so reliable... The only drawback is that the efficient heatsink could be made almost half the size for more Z space, less vibrations and less weight (hence my smaller, low cost --and low quality-- copycat by the way, see below). And it does not mean I stop thinking ;)

About Me

My Photo

If you know me and you cannot tell exactly what my real job is, then you probably found the right Jeremie. Check zax.fr for some pointers.

I am self-employed and I help start-ups, research centers, small companies with their needs related to computers, sensors, data processing and mechatronics. If you have a project and know what "R&D" is, then you already caught my interest ;)