Printing metal (2023 Update)

Yes.

Selective laser melting works with titanium alloys, chrome-cobalt alloys, stainless steel, and aluminium.

Electron beam melting works too.

It's probably going to be horribly expensive, but the techniques have been around for years now, and you should be able to find a potential subcontractor close enough to visit.

3d printing is in the stage that micros were in the 70s: wild evolution with lots of new possibilities being explored and niches being filled.

There are several ways of printing metal. Bill mentioned SLS, and that is used for specialist components (aerospace, medical, etc).

One method available to amateurs is lost wax printing. I've used Shapeways to print brass. They will also print gold, but that is somewhat expensive.

I've seem info on an amateur producing very high-quality intricate aluminium castings using a 3D printed plastic pattern as "lost wax".

It doesn't need to be wax. To be able to 3D print a pattern then use normal casting processes is very powerful.

CH

I was more interested in folks who've actually *done* it (or "had it done") to get a feel for the issues that arose in the process.

[I hacked together some plastic prototypes of a different assembly to test for fit and function -- willingly ignoring appearance. But, found that they were inferior mechanically to injection molded parts -- they sheared along the laminations when "snap-fitted" together. I'm hoping a service bureau will produce more robust parts but may need to change the orientation of the part to get the laminations to "cooperate"]

E.g., printing "lack of detail" is often just wasted money (and time in the printer). So, if the "detail" could be assembled ONTO something "more traditionally manufactured", there's some low hanging fruit (economies) to be gained, there.

Likewise, post-processing/cleanup is always an issue. So, the effort saved printing has to also include the costs of making a *usable* part (not just an outline of one).

By contrast, *machining* prototypes already has that sort of cleanup baked into the base part.

[And, a casting beats the printed part on cost but also bears the "post-casting" work]

Of course, each "production technology" has consequences to the design so getting a handle on that early on can save headaches, later!

Yes, that's how much dental work is/was produced (e.g., crowns).

Shouldn't be a problem with nylon or SLA. Very definitely a problem with domestic PLA/ABS printers.

The Shapeways pages have a good description of what's achievable in their processes.

Finish detail and precision are good with wax/metal and SLA. Nylon is better than PLA/ABS

This was done for a project I did the electronics for over 15 years ago. We had a machine shop, but it was deemed cheaper to get these made externally by laser sintering.

They were small helical impellers for a multi position flowmeter and were about 2" long, 0.5" diameter in Titanium. Very good quality but I don't remember who or where. I guess it's more common nowadays.

I think the product ended up using plastic impellers. Still not cheap as these are machined from something high temperature, stable and resistant to chemical attack. Don't know what.

I hadn't planned on actually trying to USE the few parts I made. Rather, got curious to see what they would look like "mated"... then discovered the material wasn't suitable for those types of forces over very short distances.

<shrug> That's why you make prototypes!

I've "reviewed" several service bureaus so know what they

*claim* -- and, some of their sample pieces look very nice! But, I haven't settled on a design until I'm reasonably confident about how I will make the pieces (short- and long-term) [I'm not an ME so a lot of this is hit-and-miss on top of common sense]

Some surfaces I'll need to be able to press fit bearings, etc. So, dimension as well as low Ra/z/q are significant design constraints. (hence the potential appeal of post-processing)

Time to check on the ice cream...

Hmmm... interesting. Most places that I've worked (or with which I've worked) that have had any sort of "additional facilities" (shake-n-bake, wave, pick-n-place, PCB fab, machine shop, etc.) have pushed to use THOSE facilities, wherever possible. Odd that your firm would have taken the opposite approach (presumably, you had the skillsets in-house as well as the kit?).

But, I wasn't always aware of burdened rates for these sorts of facilities so couldn't attest to their ACTUAL "economy".

So, they were machinable parts (else doing it yourself wouldn't have been an option). Did anything "special" have to be done to accomodate the outsourcing? Did you just turn over CAD files and a purchase order?

Yeah, I got a tour of a ball bearing factory when I was a kid. At one point, a display of products they'd made "locally" -- of course, the exotic stuff is all anyone really has an interest in). I asked the CEO about a *glass* bearing -- which seemed odd (until you realize most bearings don't carry any static load).

He sent an underling off to find the engineer who'd designed the bearing to explain it's purpose and design criteria to me. IIRC, it was used *in* a corrosive stream for the shaft of a large pump (the balls were an inch in diameter with an outer of ~6 inches)

Amusing to see what you can do when you feel like spending money!

(also saw some stainless steel bearings with ~36" inners -- in a pile marked "scrap"... THAT had to be painful!)

Doable, but wouldn't an off-the-shelf CNC service be cheaper?

Best regards, Piotr

It may just have been workload, they were always busy.

It was the mechanical engineer who did that, but I think so. [There were about ten each of mechanical and electronics engineers. Easy to tell who was which - they all wore shirts, ties and polished shoes, we all wore jeans or shorts, t-shirts and trainers or sandals.]

Last time I priced it, it was EXTREMELY expensive per cubic cm, and the parts went though a sintering and another process to fill the pores with a second metal.

I used the same outfit to CNC machine some cup-shaped parts out of aluminum and it was relatively reasonable.

The parts had a spherical shape on the bottom and flattened areas on the top to fit at the bottom of a 4K dewar (plus slots and threaded holes and that sort of thing). So not the sort of thing Joe Blow machinist could crank out on a manual lathe very easily.

I don't want to have to "hold any hands" as that increases the cost in far less desirable ways!

Yeah, each of my employers would gently -- but firmly -- remind me to wear a tie. I never did (unless I was representing the company to guests or clients). "You didn't specify a dress code as a condition of employment..."

One, otherwise attractive, job offer I turned down and, when the HR person asked "why", I flatly told her "everyone in your office was wearing a tie..." and let her figure out the rest! :> Given the salary offered, I suspect she found that odd!

My normal attire, for the past 30+ years, has been jeans and T-shirt. The past 6 or 7 it has been jeans and THE SAME T-shirt (I have 7 identical T-shirts from which I simply select the topmost). Every 2 years I replace the 7 with 7 more of an alternate "style" -- then switch back to the previous style two years after *that*.

It makes "deciding what to wear" a complete no-brainer! (socks are all the same color, etc.) :>

[The two different T-shirt styles were gifted to me by a friend (22 of one style and 18 of another) as a joke -- because she complained that I ALWAYS wore a black T-shirt (both of these styles are black, but with something printed on the front -- her idea of "spicing up" my appearance).]

I just can't see wasting time trying to decide WHAT to wear (or, hunting for a "matching sock"!)

Don Y snipped-for-privacy@foo.invalid wrote in news:sb0a06$h3q$1@dont- email.me:

Only costs about $12k to find out.

How about metal vapor deposition for films as thick or thin as you want

Robert Baer snipped-for-privacy@localnet.com wrote in news:16a5329db549bbf9$1$107610$ snipped-for-privacy@news.thecubenet.com:

$10k and you are in!

I have a laser engraver, and a 3D printer. I want to work my way up to a metal set-up so I can do proto stuff for folks. It even does Inconel!