Forget the 3D printer in your house

[TechMan]

http://www.foxnews.com/tech/2014/01/21/navy-helps-fund-3d-printing-buildings/?intcmp=features

Partially funded by the Office of Naval Research and the NSF, Countour Crafting is working on developing a building that is printed with a 3D concrete printer.  They want to be able to build a 2,500 ft² building in a day.  The founder claims to be able to "print" 10,000 psi walls.


Link to Contour Crafting: http://www.contourcrafting.org/

[roo_ster]

Pretty darned cool.

[geronimotwo]

a new age dawning!  that's amazing.

I wonder how they clean the "print" head?

[cordex]

I wonder how they clean the "print" head?

Free modern art statue with every house.

[Northwoods]

Wonder about the cost.  Bound to be hideous at the start.  Be interesting to see if can become cheaper than stick built.  It should as long the machines aren't still $megamillions after a few years.

[Firethorn]

a new age dawning!  that's amazing.

I wonder how they clean the "print" head?

After using it for concrete?  Probably water, lots and lots of water.  A hammer & chisel if some sets in a way that's annoying/intrusive.

BTW, this tech is at least 5 years old, though this might mark a milestone.

One nice things I was reading is that all the supply lines - water, power, data, and such would be installed in pre-created conduit.  Makes upgrading easier.  I wonder if it'd be possible at that scale to utilize a multiple material print system?  I mean, right now 99% of 3D printers are mono-material.  I'm picturing about 4 materials going into a house - concrete, insulation, permanent plastic and temporary plastic.  Concrete for structure, insulation for energy savings, permanent plastic where concrete isn't appropriate(lining conduit slots, perhaps?), temporary plastic would be low-temp stuff that provides support for the rest where necessary(doors, windows?) until printing/curing finishes.  After the install you go in with heat guns/knives and 'carve out' the low temp plastic for recycling.  Keep it clean and that could be as simple as dumping it back in the melting-pot.

[geronimotwo]

don't forget extra heads so they can print the conductors and plumbing fixtures!

[Firethorn]

don't forget extra heads so they can print the conductors and plumbing fixtures!

That would be nice, but conductors takes insulation, and not of the sort of plastic used in thermal 3D printing.  Plumbing fixtures would take porcelain, which again isn't that realistic yet.

There are some things that are still cheaper to buy and install.  Thing is, with conduit all over, installing electrical is dead easy.

[Tallpine]

This must use some sort of special blend of concrete that you can "pour" even a few inches without a form 

And how the heck do they keep that wall from collapsing until it cures 

Where is the steel reinforcing 

[RevDisk]

This must use some sort of special blend of concrete that you can "pour" even a few inches without a form 

And how the heck do they keep that wall from collapsing until it cures 

Where is the steel reinforcing 

http://www.youtube.com/watch?v=rH7vtQlS_XQ

[Tallpine]

http://www.youtube.com/watch?v=rH7vtQlS_XQ

I still don't see what keeps the sides from blowing out.   

I've actually poured quite a few concrete walls in real life.

[towercam]

http://www.wimp.com/printerhouse/
Clearing the head might require a fire hose.

[AJ Dual]

I still don't see what keeps the sides from blowing out.   

I've actually poured quite a few concrete walls in real life.

http://www.3dprintingera.com/3d-print-your-house-in-a-day/

Jump to about 6:45 in the video to see an actual prototype concrete print head in action. Whatever it is they're doing, the lateral tensile strength seems to be pretty high, although I don't know how long between rows they're waiting, but it at least still looks to be "wet", and they've gotten several feet high (3-5'?) without any significant blowout or slump.

I'd guess at a minimum it's fiber reinforced, and low slump/no slump, since finishing or working time is effectively zero, as long as it pumps and it forms where the print head puts it, they don't care.

[MechAg94]

So this thing could come in and build walls around your place real quick to keep out the zombies. 

[AJ Dual]

So this thing could come in and build walls around your place real quick to keep out the zombies. 

Even better, print big concrete cylinders the width of your defensive line, propped up with temporary chocks you can just kick out and let it just act like a giant rolling pin.

[Firethorn]

This must use some sort of special blend of concrete that you can "pour" even a few inches without a form 

Did you know that they have concrete that you can spray a lot like foam?  They use it to build dome homes.  You set up an outer 'shell' that becomes your vapor layer, inflate it, place your rebar(on the inside!) then you stand there and spray the concrete in to cover the rebar.  I'd give you a youtube link, but video is blocked here.

And how the heck do they keep that wall from collapsing until it cures???

The most recent version of the technology uses a different 3D printing technology to print supports/fill channels.  Before this they could only print vertically.  Then afterwards workers stop by and remove the supports.

Where is the steel reinforcing 

The 'new' thing is fiber reinforcement - you put the loose fibers right into the mix and pour.  It's not quite as good as rebar, about the same as steel mesh, but you don't have to worry about it rusting out.  When you're spraying/3D printing in concrete, you don't use the cheap stuff.

As a bonus, the walls might actually last longer than steel reinforced concrete - the fibers won't corrode like steel would, making the structure last longer.

[Tallpine]

Did you know that they have concrete that you can spray a lot like foam?  They use it to build dome homes.  You set up an outer 'shell' that becomes your vapor layer, inflate it, place your rebar(on the inside!) then you stand there and spray the concrete in to cover the rebar.  I'd give you a youtube link, but video is blocked here.

Yeah we have some friends that live in a house like that.   

I think they used something like wire bristles for reinforcing.  Actually, it is a combination of foam and concrete.  I think they sprayed the foam first (outer layer), let it harden, and then sprayed concrete on the inside.  Then peel off the outer layer for re-use, and spray some sort of weather coating.