3D Printing - General Thread

[Gordon Ferguson]

Well, to put it more simply

Thank God you did not over complicate it  

[finescalerr]

Actually, he didn't overcomplicate it but I know you were joking. I think, if I were to try to explain some aspects of jazz or harmony, my "simple" description might still baffle some people. As Einstein said, "Things should be as simple as possible, but no simpler." -- Russ

[Frederic Testard]

Bexley, as I understand it, if you are able to describe a shape in terms of triangles and write it with the correct syntax, you'll have a STL file. Is it automatically printable (assuming there's no 'open' place where the triangles wouldn't exactly meet)?

[Hauk]

Bexley, as I understand it, if you are able to describe a shape in terms of triangles and write it with the correct syntax, you'll have a STL file. Is it automatically printable (assuming there's no 'open' place where the triangles wouldn't exactly meet)?

No, a .stl file is not automatically printable. Printers will have limits to what they can print, often related to things like minimum wall thickness, slot width, minimum feature size, overhangs, etc.

The need for support structures during printing can limit what can be printed. Caveties must be possble to drain for uncured resin etc.

But these things are printer specific, and one should check the requirements of the printer the part is to be made on.

[Bexley]

Bexley, as I understand it, if you are able to describe a shape in terms of triangles and write it with the correct syntax, you'll have a STL file. Is it automatically printable (assuming there's no 'open' place where the triangles wouldn't exactly meet)?

An STL is not automatically printable. However, the only real requirements to be printable is that it be manifold and have consistent normals.

Manifold (in 3D geometry, not mechanics or mathematics) means it is essentially a "watertight" shape, which is what you described- no open spaces, no gaps between polygons.

Consistent normals rarely comes up as an issue, but what it means is that all the faces "point" the same way, and they point outwards. Each polygon has two "sides" mathematically, and one of those sides is designated "normal." In a solid watertight shape, all the outside faces also have to be normal. It's rarely an issue, though, because most software is good at generating and retaining correctly facing normals. But it can happen that something might invert some of them, and this would cause errors. Usually merging multiple meshes into one is the cause.

Of course, "printable" doesn't necessarily imply "successfully printed." As Hauk said, if parts are too thin, or unsupported, the print can still fail. But the printing software won't reject the file.

As far as being complicated, it really isn't, there's just a lot of terminology that needs to be defined. I know the first time I heard NURBS (which, we all know, stands for Non Uniform Rational B-Spline, right? Right?) my eyes glazed over and I got confused and fell down. But once I got moved over to 3D modelling, and this stuff became relevant and interesting, I picked it up pretty quickly. Interest level has a lot to do with it. I imagine Russ would never be able to teach me even basic concepts about music, as it doesn't much interest me. There's nothing wrong with being uninterested in a subject. But it does bug me when people say something is beyond them when it likely isn't, they just  have no interest or reason to be interested in learning it. Which is a perfectly valid stance to take- I'm not trying to be insulting about it.

[Chuck Doan]

If the requirement is to be consistently normal, then I am in big trouble.

On another note, I just read that UPS stores are going to offer 3D printing services. Walmart can't be far behind! Or Starbucks. 3D print a mug with the coffee inside.

And then there's this: http://www.wired.com/gadgetlab/2013/08/makerbot-digitize/

Go ahead put the kitty on the turntable. You know you want to.

[Hauk]

And then there's this: http://www.wired.com/gadgetlab/2013/08/makerbot-digitize/

Go ahead put the kitty on the turntable. You know you want to.

Well, to get a good scan I think Kitty needs a night in the deep freezer, so I think I will pass.

On a more seriouse note, a digitizer offers interesting possibilities. But what I would really love is an affordable digitizer that can handle full-size parts. As I work in 0-scale, it only needs 1/45 the resolution of the best printers.

[David King]

http://www.youtube.com/watch?v=Oie1ZXWceqM

If this technology produces models compatible with 3D printing it takes away much of the 3D modeling learning curve out as an obstacle to adoption.  What implication does this have for model building?

David

[mad gerald]

G'day all,

sneakers (um well, at least trade samples) generated by a 3D-printer (only in german - sorry for inconvenience) ...

http://www.abendblatt.de/hamburg/article120135002/3-D-Technik-Turnschuhe-aus-dem-Drucker.html
http://img.abendblatt.de/img/hamburg/crop120137389/3810696569-ci3x2l-h307/3D-Drucker.jpg

... it is also reported in that article, that a modell of a complete house has been printed (costs approx. EUR 300-400) with that printer as well as some cochlea-implants.

Printing a sample of a ball bearing was done - costs: EUR 8  ...

The price for that kind of 3D-printer may be still exorbitant, but it seems the printing costs tend to reach a reasonable level ...

Cheers

EDIT: Sorry, article has now limited access only - in case of interest a similar article is still readable here: http://www.welt.de/print/die_welt/hamburg/article120134560/Turnschuhe-aus-dem-Drucker-als-besonderer-Clou.html

[marc_reusser]

I have a friend who is also an architect. He was doing some work for a client that has access to a hi res 3D printer. They printed the entire 3000 sf house remodel on the printer....including interior walls and doors. It was done in interlocking sections and then glued together to become the whole model. I think they did it in 3/16" or 1/4" scale.

[finescalerr]

Didn't you once post a link to somebody who used a 3-D printer for constructing a 1:1 cement fireplace and other parts of a residence? We all must learn SketchUp! -- Russ

[marc_reusser]

That was me, with a pair of fireplaces for one of our clients. They were drawn very detailed in a 2D CAD program then imported into SU, where the 2D line drawings were extruded into 3D solids; this file was then sent to the stone yard/fabricator ...they then converted the file to whatever their machine neede......and they were cut (rapid prototyped/cnc milled), out of large blocks of limestone, in a machine the sie of a good sied bedroom. Then before shipping, workers manually went in and "hand tooled" them, to add saw cord marks, and other tooling marks, as well as some chipped and damaged areas. They were also left sitting out in the rain and weather to stain and patina them a bit.

........basically sim to the way Chuck made his brick foundation walls. 

[eTraxx]

When FUD arrives from Shapeways it has a coating of wax that needs to be removed. Warm water works .. as does alcohol. Just a note: Don't drop your FUD into the alcohol .. and forget about it for a couple of hours .. brushing and rinsing causes no problems.

[lenelg]

A chain of stores catering to electronics hobbyists here in Sweden has a 3D printer in their fall catalog, at under USD 1000. Probably not close to the precision we want, but it is an interesting sign of things to come, the "Apple I" of 3D printers..

[finescalerr]

Similarly a friend living near Tacoma told me yesterday a hobby/craft shop there offers the services of both a low res and a hi res 3-D printer. -- Russ