The Shapeways Blog: 3D Printing News & Innovation

Shapeways Blog


Initial Design rules Stainless Steel 3D printing


Comments

Display comments as (Linear | Threaded)

Thanks for the guidelines :-) Too bad I couldn't follow them... photos of my latest Shapeways Stainless Steel prints below to show the detail that can come out.. quite pleasantly surprised compared to the last print...

http://www.madox.net/blog/2009/10/24/propeller-hat-cufflinks/
#1 Madox (Homepage) on 2009-10-24 08:52 (Reply)
Madox,

they're great! A lot of fun!

Joris
#2 Joris on 2009-10-24 09:58 (Reply)
Very interesting the fact that for small object you can have wall of 1mm.
I still do not understand if we can print moving parts: I am afraid that if there is no more support material during the infusion phase, the moving parts could get fused.
For example could the Frankenstein Ring be printed in Stainless Steel ?
Here is the model:
http://www.shapeways.com/model/57670/frankenstein_ring.html
#3 Magic on 2009-10-24 10:11 (Reply)
What about printing that wine glass upside down? Would that work?

Darn gravity. Maybe you can take a 3D printer up to the International Space Station? Then anything would work!
#4 George Bell on 2009-10-24 15:00 (Reply)
great post.

I shared a link for the Ponoko readers

cheers
#5 duann Scott (Homepage) on 2009-10-26 02:59 (Reply)
Magic,

the tolerances and the accuracy would make fine moving parts difficult. Exact gears and things would seem to be difficult also. But, a moving part with a large gap should work.

Joris
#6 Joris on 2009-10-26 15:33 (Reply)
In terms of cost effectiveness we could do it in one of those Russian practice planes and do a layer every time the plane is at the top of its parabolic orbit.

Does UPS even do pick ups from the ISS?
#7 Joris on 2009-10-26 15:36 (Reply)
Currently, this model has 1 mm of clearance and 2 mm of thickness. But I have plans to reduce the model of 75% (0.75 mm or clearance and 1.5 mm of thickness) and 50% (0,5 mm of cleareance and 1 mm of thickness) in White Strong and Flexible.
I guess these reduced versions won't work in Stainless Steel.
I should also renounce to print a separate nut that could be screwed to the bolt... :-(
#8 Magic on 2009-10-26 20:37 (Reply)
Thank you, this is very clarifying and helpful :-)
Up till now it felt like modeling in the dark for SS, hoping and praying that the prints would succeed ;-)

Could you also provide some info on the polishing step ?
What limitations does this add ? Is there a minimum practical size for polishing ?
With the braille and other rings I tested, it seems they were hardly polished at all, still very rough (almost like wsf) and red.
I can understand some reluctance to polish fine details (for example; accidentally removing the braille dots ;-) but there were a few rings that I think could have been a lot smoother and cleaner.

I'll post some pics as soon as the darn memory card will release them to me :-\
#9 Stijn van der Linden on 2009-10-28 09:14 (Reply)
Stijn,

The polishing step is a manual one. So it is very variable. Polishing should not reduce overall surface detail nor significantly affect the size of your model.

We're working on improving this process but again it is a manual process so results may vary.
#10 Joris on 2009-10-28 10:50 (Reply)
So many people in London have skull rings, but this is my far the coolest.
Very Damien Hirst ;-)
#11 Stephanie P on 2009-11-16 16:20 (Reply)
What percentage of shrinkage occurs in post infiltrated parts?

Thanks,
Doug
#12 DBucci (Homepage) on 2010-06-02 21:41 (Reply)
To All,
It first needs to be recognized that 3d metal printing is a technology that is in it's infancy. Unlike traditional metal working methods with centuries long histories, many of the forces, stresses and reactions that printed metal parts must undergo have not been thoroughly quantified as hard data. Simply put, most of the time we know what works and what doesn't, but we can't always tell you exactly why. As in most technologies emerging from small companies, data collection is done on an "as needed" basis. The bulk of all human knowledge comes from data collected over years, decades or even centuries of trial and error. This might help explain why giving precise reasons and fool proof solutions for each and every failed or "non-printable" design is not practical or even possible.

From my perspective here in the metal print shop I wish to offer some observations that I believe to be consistently true. When parts come out of the print machinery they consist of metal powder held together by a chemical binder (glue). All [I]green[/I] parts are fragile. Think in terms of air dried potters clay. As the size and intricacy of a design increases so does it's fragility. In the green state, these parts are extremely difficult to process without breaking. If a part is able to be loaded into the sintering furnace a whole new set of forces now come into play. Observations inside the running furnace are impossible so finished parts can only be examined [I]after[/I] the furnace is cooled. The most common failures detected [I]after[/I] sintering take the form of hairline cracks or open breaks. This type of flaw usually occurs in areas consisting of sharp angular intersections and/or radical section changes. The use of fillets and smooth transitions can help prevent this from occurring but not in every case. Flat broad thin meshes and grids are very often problematic but not always impossible. The overall size to mass ratio does seem to play a factor but no generalized rule has yet to be determined. Actually, it would surprise me if the use of the true "Golden Ratio" (1.618033......) didn't improve any design intended for 3dmp.

Forgive me if these comments seem a bit vague but currently it is simply the nature of the beast. I truly believe that [I]everyone[/I] involved with these new technologies is now acting as a contributor to a global knowledge base. Whether designer, businessman or technician, we are all together writing the book on 3d printing/manufacturing. Pretty exciting stuff really!

-Glen Gardner
#13 Glen Gardner on 2010-11-16 19:41 (Reply)

Add Comment



Enclosing asterisks marks text as bold (*word*), underscore are made via _word_.
Standard emoticons like :-) and ;-) are converted to images.

To prevent automated Bots from commentspamming, please enter the string you see in the image below in the appropriate input box. Your comment will only be submitted if the strings match. Please ensure that your browser supports and accepts cookies, or your comment cannot be verified correctly.
CAPTCHA

  
  
The Shapeways Blog: 3D Printing News & Innovation

Learn More »