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...