Cheap, 3d-printed inner grids

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Carl Willis
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Re: Cheap, 3d-printed inner grids

Post by Carl Willis » Wed Feb 06, 2013 7:16 am

I just don't see how 3D printing would result in a solid, durable piece of metal. Wire is solid metal drawn through a die. 3D printing is usually an accretion of particles in some kind of binder. With a site like that one, you can upload any design you want and it will figure out a price automatically, but it can't tell you if the piece is actually viable mechanically or has materials in it that are suitable for being used in a fusor. You should probably get someone familiar with the 3D printing process at that website to advise you on whether the part can actually be made as drawn.

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Rich Feldman
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Re: Cheap, 3d-printed inner grids

Post by Rich Feldman » Wed Feb 06, 2013 3:05 pm

More along the lines of what Carl said.
What I would do is make a test part with a series of bar thicknesses and orientations. The bars would be long enough for destructive tests of their stiffness, bending strength, and ductility. And would go thin enough to probe the limit of fabricability. As if it were a new foundry-for-hire, offering to cast an unfamiliar material.

In either case, the first step is to ask for material specifications and dimensional design rules. For a less technical, consumer- or artist-oriented site, do what Carl said and just ask if your design is likely to come out as drawn. If the price is really under $10, the answer might be "try it".

I'd like to see if your 3D print shop compensates for shrinkage in the firing process. If the shrinkage is sensitive to bar thickness, then parts with large disparities might end up with internal stress, or even break while hot.
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Richard Hull
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Re: Cheap, 3d-printed inner grids

Post by Richard Hull » Wed Feb 06, 2013 4:34 pm

Carl and Rich have valid points. We have no history related to powdered metal assembly resulting from 3-D printing thermal cycling stresses, etc. A powdered metal, even strong sintered metal would represent a new high in hydrogen absorption. Only testing in the real environment would tell the tale.

We know that drawn wire responds well even with extreme embrittlement, which for it is a plus, as all the tensions due to flexure during assembly within the structure are released over time in the fusor environment, freezing it to a specific shape.

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Fusion is the energy of the future....and it always will be
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Re: Cheap, 3d-printed inner grids

Post by John Futter » Wed Feb 06, 2013 8:53 pm

Anthony
metal additive processes can make 99.98 percent dense output with around 30 micron granularity.
the laser sinterer near here makes SS 316 and Ti and Ti 46 alloy parts with the above performance and yes I have seen an impossibe to build any other way buckey ball within a buckyball test piece.
It is interesting to note that the parts are at least 99.8 as strong as extruded /forged parts.
I'm not sure of how the ebeam sintered parts compare but they should be comparable

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Re: Cheap, 3d-printed inner grids

Post by Chris Trent » Thu Feb 07, 2013 4:37 am

Here is the admittedly non-technical reference page for the stainless material at shapeways.

http://www.shapeways.com/materials/steel

It is not e-beam sintered stainless steel, more like bonded and brazed stainless powder. I have by doubts if they can actually manufacture the shape, but if they can it will be interesting to see someone try it.

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Donald McKinley
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Re: Cheap, 3d-printed inner grids

Post by Donald McKinley » Thu Feb 07, 2013 8:13 pm

Honest question. If it works as a grid, does it really have to be strong and durable? I don't recall any information about how strong except if its too thin, it's probably too easy to melt.

Other items work pretty well without much strength. A coleman lantern mantle for instance. And it gets much hotter.

Go for it Anthony, let us know.

D

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Richard Hull
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Re: Cheap, 3d-printed inner grids

Post by Richard Hull » Mon Feb 11, 2013 3:54 pm

We have talked about a lot of ideas related to fusor structures, components and other minutia, but about 80% of the bold ideas are pretty much "wind over the decks".

As always, we might not really expect to see this idea actually implimented in a functional, fusing device here.

Much like power ready fusion, we will all just have to wait and see what really transpires down the road a bit.

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Dany_B_Drolet
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Re: Cheap, 3d-printed inner grids

Post by Dany_B_Drolet » Mon May 06, 2013 8:24 am

First of all, sorry for necro post, but the forums here aren't that active.

Second, I work in a 3D printing and additive manufacturing shop. The owner, which I know well since we're just a handful of people there and since I'm pretty much his R&D assistant (my title is pretty ambiguous), is a proven physicist specialized in nano-scale deposition systems. He shown me some printed metal components and we have all the machinery to make the grid. I'm not sure I'll take your grid model, but I'll talk to him about making one (probably using SLS) and try it in my Fusor project once I get there.

I can't believe how much such a device gets more and more complex as I understand it more and more... But hey, gotta persevere.

-Dan
Ignorance is never better than knowledge
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Fusor project status: Stalled. Most components acquired.
Financial problems forbid me to spend any more penny on it for now.

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Re: Cheap, 3d-printed inner grids

Post by John Futter » Mon May 06, 2013 9:41 am

Hi all
Dany is right
open your minds to impossible to machine items

I have had Ti6Al4V items made that are extremely good more later when it becomes public

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Dany_B_Drolet
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Re: Cheap, 3d-printed inner grids

Post by Dany_B_Drolet » Mon May 06, 2013 11:07 pm

Heard me when I talked about using *additive manufacturing* ? Using SLS, I am certain to be able to print it in aluminium, then smelt it to create a perfect grid. I am not sure about other alternatives. But my boss is working on much more elaborate techniques using nanoparticles. Gotta ask him this week.

Impossible to machine yes, but you can still build it from the ground up!

EDIT: Oops, looks like I misinterpreted your message, John. Sorry for that!
Ignorance is never better than knowledge
-Enrico Fermi
-------------------------
Fusor project status: Stalled. Most components acquired.
Financial problems forbid me to spend any more penny on it for now.

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