I am looking for info on Direct Metal 3D printer

I am looking for a Direct Metal 3D printer for the purpose of small scale manufacturing from my home workshop.
I will therefore require a system that will run on a residential power grid, ergo 120 or 240 volt 60hz.
I also have requirements in the area of Build capacity, 24"x9-13/16"x9-13/16" but ideally would prefer 24"x24"x12".
I need to print in aluminum, cobalt chrome, stainless steel. also titanium would be nice but not necessary.
I have scoured the net for days to no avail. So if any one can provide the information I need, such as who makes one, where to find (such as a website), and the cost. It would be greatly appreciated.
:D

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Originally Posted by madmanmax

...from my home workshop...titanium...

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You must be loaded, your looking at $500K-$1M machine range.

Machine: EOSINT M 280
EST Cost: $630K

with a build volume of that size im sure it would be a machine well over $1m.

My intention would be to find investors to help with the cost.
But first I need to find a printer that will do what I need.
I've been unable to find one big enough, and those in the power range have been small.
The bigest one I've found only gets me to 14 inches but I need at least 24 inches.

I know they are out there. Just not sure who makes them. SpaceX has a really large one like that which they do rocket engine components with.

Concept Laser 1000R - 630 x 400 x 500 is about as big as you can get using metal powder. = 1.5m Euros maybe

Can probably get larger through CNC based deposition version.

You're not going to 1000w laser running on your power supply however, and you would need a serious business plan to get some people on board such a thing.

- The only company I know of that has a large build volume for metal printing is Sciaky which prints at an enormous volume of 19' x 4' x 4' (L x W x H). Not sure on the cost, you'll have to call for a quote.

- Whitney Hipolite also wrote an article on it HERE on 3dprint.com.

Printing with aluminum and titanium can also be dangerous. https://www.osha.gov/pls/oshaweb/owa...SES&p_id=26019

Powdered titanium is used in pyrotechnics and is quite explosive. Not ideal for a home operation. That's why any jewelry store selling those alloys will not size them. They typically offer exchange plans instead so you can swap them out if you need a different size. Putting a torch to a titanium ring is a major no-no.

Plus, most metal printers I've seen (the relatively affordable, non-aerospace metal printers) produce items will appalling surface quality. Lots of post-processing work.

I can attest first hand that titanium fires are a real problem if you have dust buildup. Had a grinder full of titanium dust catch a spark from a Ti Part I was grinding. Had to let the fire burn itself out (wasn't big enough to use the metal extinguisher, too much paperwork). Ruined the grinder though. Was using a flapper wheel on the grinder, so it acted like a fan, so it turned the exhaust port into a flamethrower.

- Its extraordinarily dangerous as bford903 and Marm mentioned. Metal powders can have disastrous results if improperly handled or if exposed to the wrong environment. Just mixing some aluminum with rust can create Thermite (which is fun to play with), it burns at around 2200C and cannot be put out easily. A small pile (about the size of a large coin) on the hood of a car will melt through the engine block and into the concrete below. So working with a vat of metal powder to me is a bit frightening.

Here's some interesting metal facts I got from the University of Pittsburgh HERE

Titanium (Ti): Specific gravity, 4.51; melting point, 3040°F (1670°C). At red heat, 1300°F (704°C), the metal actively decomposes steam. Following strong nitric acid treatment, the metal may explode by the light impact or friction of handling with tongs. The powder can be ignited in pure carbon dioxide above 1260°F (682°C), in nitrogen above 1475°F (801°C), and in air at 626°F (330°C) to 1094°F (590°C). Powdered titanium immersed in water or wet with water at ordinary temperatures has been ignited by chemical reaction.

Aluminum (Al): Aluminum is used both as a commercially pure metal and as an alloy. In finely divided powder or dust form, aluminum and its alloys are combustible in air and present a serious combustion explosion hazard. Aluminum will react violently with many chemicals. Aluminum particles and smaller turnings will react with water to form hydrogen gas which is highly flammable and explosive in favorable concentrations. The rapid vaporization of water in contact with molten aluminum can result in rapid phase transformation explosions. Halogenated extinguishing agents should not be used.

Do tell me more about when it burnt the grinder, for the sake of a pyroman!

Like I said, I was deburring the edges of 3" tubes, about 5' long, using a flapper wheel (sandpaper basically) that was on a grinder. It was the type of grinder that had exhaust ports to be hooked upto a suction unit to be collected in a 50 gallon drum, except we didn't hook it up because we didn't want 50 gallons of dust right behind a spark machine. So, with the guards and circular housing of the grinder, the flapper wheel was basically a centrifugal pump, but with air. There was a small pile of dust on the bottom of the housing that we'd clean out every so often, but most of the dust just blew out on to the floor, which we'd sweep up at the end of a shift. (Sounds like a problem, but there wasn't a lot of dust, trust me). Every now and then the wheel would throw a spark from the tube, and it'd spin around the housing a few times going weeeeeeee! and go out. Well, one time, it threw a bigger spark than normal, and it planted itself right into the pile of dust. With the wheel acting as a blower, it quickly ignited. Had about a 2-3' yellow white flame shooting the back of the grinder for a minute or so. Turned off the machine and as the wheel slowed, the fire went out. But the power cord had been laying just close enough to be melted by the flames.

AL could be done with a MIG welder on a suitable gantry. I have seen SS done by a remote controlled TIG setup.

Are you looking to do Sintered metals or solid metals? For such a small physical work volume, unless the design precludes it, standard subtractive machining might be the better option.

LarryC, I need greater detail than could be achieved with a welder. my intention is to do things that would otherwise require casting.
The rest of you are all right about the flammability and explosive property of aluminum and titanium when oxygen is present.
Most printers for these materials use a sealed chamber filled with argon gas, therefor no oxygen and no fire potential.