Shapeways, Here We Come?

[Hauk]

Long time, no post, but I have not lost all interest in modelling.

Tonight we can present the latest findings from the local 3D-printing test dept. Seeing some rather promising results made in brass by SW, I have been eager to test their brass printing service. Or more precicely, their wax printing and brass casting service, as they print a wax master and cast an one-off lost wax casting.

I have a coupler pocket in 0-scale tat I use for tasks like this. There are 12 pieces assembled into a package measuring 1.287" w x 0.362" d x 0.194" h .

Here are the result:





I have mixed feelings about the results. I think they are surprisingly crisp for the size. You can clearly tell that there are hex-nut bolts and not rivets in the parts. But the surface has a uniform pattern that is annoying. I think the roughness is ok, had it been non-uniform it couls easily pass for a rough casting surface.

Here is a primed FUD part for comparasion:



As I am planning to use the parts directly for some brass rolling stock, I think I prefer the brass parts. It will be interesting to see the parts after priming. Detail is comparable, me thinks.

Here is the .stl file:



Conclusion: 3D printed parts are still not as good as parts made by traditional methods, but we are getting there!

[finescalerr]

I agree that the brass parts look better than FUD resin. Actually, much better. And I agree that the pattern on the brass is pretty obvious, especially considering that 1:48 scale is "medium size", not small like HO or N.

Even so, overall the brass casting looks quite good. Do you think sandblasting or some other technique will help very much?

Thank you for showing us what to expect from 3-D printing.

Russ

[Hydrostat]

Very interesting, Hauk. I agree with Russ - try sandblasting the items. Which prize is the SW compared to local providers?

Volker

[5thwheel]

the brass looks nice.  i think a little work with an air eraser will help with the texture. My experience from my white metal casting days is that to get crisp looking hex (or square) nuts and washers is to obviously undercut them a bit.  This will eliminate the fillet formed by the primer and paint. When making patterns for casting you should allow for what painting will do.

[Hauk]

Very interesting, Hauk. I agree with Russ - try sandblasting the items. Which prize is the SW compared to local providers?

Volker

First I will give them a coat of primer. If that does not cut it, I will try the air eraser. But you will loose some of the crispness using an air eraser/sandblaster.

But for parts without any sharp features sandblasting should work great. For instance, I am in the process of designing a master for a spoked wheel center. The prototype is cast iron, and has mostly quite a rough surface. The smooth areas are machined, but these will be machined on the model as well.

The price of the brass part is around USD 25 incuded postage and handeling. Quite costly, but for casting masters the cost can be justified.

[Chuck Doan]

Thanks for the test and for sharing the results. I was wondering how they did the metal parts. The problem is lack of control over the master. Since we can't control the print direction I have been sending part clusters with the same item's arraigned on different faces and in different orientations. I usually get some better printed than others. A compromise until printing accuracy improves.   

[Lawton Maner]

Rio Grande Jewelry Supplies has 3 different sized Rapid prototyping machines in their 2014 catalogue.  "Call for prices".  Their illustrations also have the same surface texture as the pars here.  I suspect it has to do with the wax used and the technique used to lay it down.  I doubt if the wax can be delivered to the build up in as small pieces as the resins can.

[Hauk]

I think we are *very* close to affordable 3D printing with a quality even the most discriminating modellers will accept.

Check this out:
http://www.nbcnews.com/technology/theyre-multiplying-3-d-printers-go-big-small-2D11876898?ocid=msnhp&pos=7

Take a look at the Kevvox printer, it has a price tag of around USD 17 000. Not the cheapest around, but the minimum layer thickeness is 10 µm or 0,01mm. The Solidscape printers has a minimum layer thickness of 0,0127mm.

In other words, the Kevvox printer should be able to rub shoulders with the Viper printers used by FineLine prototyping. We all know the quality AND the price of those parts!

Here is a link to an image of a 80mm (3") high figurine:
http://fabbaloo.com/storage/Kevvox%20Sample.jpg?__SQUARESPACE_CACHEVERSION=1387402551379

This is getting quite exiting!

[finescalerr]

Now we seem to be getting somewhere. The price to print something of an acceptable resolution might, in my case, be worth the savings in the time to create it. And that doesn't even take into consideration my crude skills vs. the near perfection of computer designed and produced parts.

Do you have an idea of the cost to print one of those little figures and who does work of that quality?

Russ

[Hauk]

Now we seem to be getting somewhere. The price to print something of an acceptable resolution might, in my case, be worth the savings in the time to create it. And that doesn't even take into consideration my crude skills vs. the near perfection of computer designed and produced parts.

Do you have an idea of the cost to print one of those little figures and who does work of that quality?

Russ

I just found out about the Kevvox printer today, but I will start searching for a service provider that uses one of these machines.

A little follow-up on the brass parts from Shapeways, I gave them a shot with some Tamiya primer this evening, and here are the results:



The regular pattern on the parts have almost disappeared under the paint. That you can still see the pattern in some places is due to the fact that it is very difficult to get an even coat of paint on parts with as much relief as these. The paint is not nearly even enough. So we are really moving from discussing the quality of the parts to my skills with a spraycan. (Changing the image to black& white was to hide the brass color still visible in areas with poor coverage). In the areas that have full coverage of primer, the pattern has disppeared. Of course, you loose a bit of detail sharpness in the process, but that is the case when painting a perfect injection modelled part.

My conclusion is that for normal viewing (close up with really good lighting and reading glasses on, no optivisor!) and photographed at up to moderate macro ( normal picture angle, app. 3" from the lens) the quality of the parts are more than good enough.

And for parts that can be given a shot with an air eraser (Like spoked wheel centers that will have critical surface machined)  the quality will rival even the best handmade parts by a very skilled patternmaker.

Thats my opinion, anyway...

Regards, Hauk
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[Chuck Doan]

I will be very interested in those new printers.

[marc_reusser]

I am curious, I don't recall if it was from Shapeways, but I have seen wax masters that were printed for jewelry casting that had almost zero surface texture (it was a dark green color wax). 

[Bexley]

Envisiontec makes several printers that get pretty close to that.


(Speaking of which, the down payment on ours goes out Wednesday, and it should be delivered next week. At which point we need to schedule two days for their tech to come out, set it up, and run us through the training program. I'm particularly looking forward to getting to play with the software that comes with it, which automates support generation and has a lot of fancy mesh manipulations like shelling, both of which we currently have to do "by hand.")

[Hauk]

I am curious, I don't recall if it was from Shapeways, but I have seen wax masters that were printed for jewelry casting that had almost zero surface texture (it was a dark green color wax). 

Could it have been SolidScape prints?
I have a friend that have his own Model Railroad company, and he makes a lot of brass castings from printing masters. 
He claims that nothing rivals the Solidscape prints. They are the standard he measures everyhing else against.

The only drawback is finding reliable and affordable service providers that can also provide a casting service. The wax prints are useless for anything else than a lost wax master. The wax masters are very fragile, so you need a caster close to the printer.

Here in Norway you must expect to pay around USD 150,- for  a Solidscape wax print including a brass casting.