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Storen
12-07-2016, 11:59 AM
Can someone help me with information on the available options for precise 3D printers for wax-like materials suitable for jewelry.

Requirements:

Important:
- Ultra high resolution and surface quality - 10µm (Z) or less.
- Optimized material for Direct Casting
- Relatively inexpensive (for small shop)

Not important:
- Build Size
- Build Time
- Cost of material
- Maintenance complexity
- After sale support

I am not very experienced with the brands, technology and cost. I would very much appreciate if someone could advice me on that.

ihavenofish
12-07-2016, 12:15 PM
solid scape printers are just for this. they are small, and "relatively" cheap (at about 25k). build volume is 150x150x100mm, and runs about $7000 to fill that entire volume, which is quite alot of jewelry. its pretty cost effective on small parts that can be well packed. on large hollow space inneficient parts, its probably not worth the money.

theres nothing in the super cheap hobby territory that i know of that is viable for real work - otherwise id already own it :P

Storen
12-07-2016, 12:38 PM
solid scape printers are just for this. they are small, and "relatively" cheap (at about 25k). build volume is 150x150x100mm, and runs about $7000 to fill that entire volume, which is quite alot of jewelry. its pretty cost effective on small parts that can be well packed. on large hollow space inneficient parts, its probably not worth the money.

theres nothing in the super cheap hobby territory that i know of that is viable for real work - otherwise id already own it :P

Thanks much ihavenofish. I've heart Solidscape are one of the main players. Do you know what technology their machines use? I am a little confused by their spec - everting is in DPI and not in metric measurements like the other brands:

5000 X 5000 dots/inch (197 X 197 dots/mm) in X, Y
8000 dots/inch (315 dots/mm) in Z

If I interpret this right it means that the pixel size (X,Y) is 5µm and the layer thickness (Z) is 3µm. Am I correct?

How would you compare it to DigitalWax 009J which sells for about the same price?

What do you think about the cheaper options like XFAB, PICO2 and B9CreatoR?

Thanks again!

ihavenofish
12-07-2016, 01:21 PM
i only rerally have a bit of knowledge of the solidscape as i entertained buying one a few years back. i dont know about the other brands in detail.

its bascially a wax inkject. imagine an old tectronix solid ink printer, that just prints 10000 pages on top of each other :) keep in mind that at 8000 layers per inch, prints will take a looooooong time. i think the comprmise setting is 0.0005" (12 micron) layers, which is still very clean, and a lot faster.. i forget the build times, but at max res, i think its in the several days range to build the entire volume.

the B9 is an sla printer, vaguely similar to the form labs printer (also a kickstarter if i remember right). the resolution is nowhere near as good as the solidscape, and the burnout, while they claim is perfect, is more sketchy on. xfab is the same.

awerby
12-07-2016, 04:02 PM
I've been running a B9 creator, and it does a pretty good job with jewelry patterns. It's a lot less mechanically complex than the Solidscape printers, which are a nightmare to maintain, with heated lines for the wax, a planer that has to hit each layer, and finicky jets that go bad and cost a fortune to replace (I had one once - never again). The B9 is based on a projector, so it can make smaller pieces at higher resolution or larger ones at lower res. The resin doesn't burn out as well as wax, but it does burn out cleanly if you use Plasticast investment and introduce a little air into the kiln at the end of burnout.

ihavenofish
12-07-2016, 04:09 PM
i wonder if you can employ a 3DS type printing strategy for the b9. they use some software that creates a hollow liquid free structure that will collapse on itself when burned out, reducing some of the issues you normally have with burning resin.

http://www.realizeinc.com/wp-content/uploads/2015/03/IMG_4479.jpg

awerby
12-07-2016, 04:43 PM
I suppose you could do that, as long as you printed your hollow structure with a drain-hole in the bottom. But casting things like that in metal is problematical, since thick blobs of metal, cast solid, tend to have all sorts of shrinkage issues, as well as being uneconomical in precious metals. You'd be better off casting things like that with cores.

ihavenofish
12-07-2016, 04:48 PM
O-o

i think you misunderstand. the print is hollow, not the casting. the hollowness is to allow the pattern to melt/burn out without expanding and cracking the mould, or leaving too much residue.

Storen
12-07-2016, 05:11 PM
Thank you ihavenofish and awerby. That's good info.

//its bascially a wax inkject. imagine an old tectronix solid ink printer

So it's like a mechanical plotter with a printing head running on X and Y sliders? That may be less precise (looser tolerances) than a laser SLA with a galvanometer. Also dealing with obstructed nozzles is probably annoying.

//xfab is the same (B9)

I think XFAB uses sold state laser and galvanometer similar to the high-end machines of the same company (DWS). I am surprised they are using so expensive parts and manage to keep the price at 5K. Probably there a catch but I can't figure it out for the moment.

The machines with Projector are significantly less expensive than the ones with Galvanometers while the specs are similar. Do you know what are the disadvantages of the Projection method?

awerby
12-08-2016, 04:27 PM
@ Ihavenofish - I didn't misunderstand. Ideally, jewelry metal castings should be rather thin; increasing the thickness of the castings usually leads to problems. Yes, theoretically there could be some advantage in creating collapsible patterns, but in practice this is difficult to do, since most jewelry patterns vary from thick to thin and trying to make the thick parts hollow and drainable just isn't worth the hassle, IMHO.

@Storen: the galvanometer/laser machines can catalyze resins easier than the projector-based machines can, since they put a lot of power in a small spot, albeit for a short time. The projector's light is more diffuse, so it needs to stay on any particular spot longer. But with a projector, you can expose a whole slice at a time, so the process is just as fast, or faster. Projector machines achieve higher resolutions by focusing the same pixels into a smaller area; laser machines work over the same space with a dot-size that doesn't vary, although they can get higher resolutions by reducing the Z steps. But they are more mechanically complex, since they have to be able to move the laser beam rapidly for each layer, while all the projector systems need to do is shine, peel, and shine.

ihavenofish
12-08-2016, 04:36 PM
@ Ihavenofish - I didn't misunderstand. Ideally, jewelry metal castings should be rather thin; increasing the thickness of the castings usually leads to problems. Yes, theoretically there could be some advantage in creating collapsible patterns, but in practice this is difficult to do, since most jewelry patterns vary from thick to thin and trying to make the thick parts hollow and drainable just isn't worth the hassle, IMHO.


ahh, i see what you mean. too thin for that method to make any real difference.