I don't know if anyone is interested in this type of thing, but I find this incredible!

Need a new caliper or door catch? Really want to re-engineer that 6.0L head? Ok, maybe not a head, yet, but it's not far off.

100x faster, 10x cheaper: 3D metal printing is about to go mainstream

 

The idea of 3D metal printing is awesome BUT I see the danger or it causing problems. The structual stability of a cast part is different to that of a printed one due to the way the material is layered.

For plastics I'd say good. For metal, well, not really mine and it yet has to prove differently.

 

Thinking.of the metalurgy of metal, interlocking grains that grow and change in the heat processes of casting.
I think printing is more individual particles glued together so no heat "welding" during the forming process. Sounds like any printed part has the potential to be weaker.

Or is my understanding of the printing process wrong.

 

3D-printed metal parts is a lot better, than most people think.
They are also a lot more expensive than the article in the OP signals. 3D print might be 10x cheaper than other methods as they claim, but it is still maybe 10x more expensive than traditional machining unless it is a small and very complicated structure.

The metal is actually melted together using the heat input from a laser beam and will be (close to) solid. A potential issue in my view is how the metal reacts to the repeated temperature cycling near the melting point when the neighbour droplets of metal is placed.

3D printing metals will not have the structure obtained by forging, and there will be small imperfections. I would therefore not use it for highly stressed parts like conrods, crankshafts and similar, but it will be perfectly ok for most other metal components in an engine or other places in a car.

 

What about say wishbones? They are normally cast and have to take some hard whacks... I personally (!) would only use this on things which don't have any load. Like say a little bracket for the crank sensor, a valve cover, maybe an intake manifold (should make it smoother as well).

 

Wishbones look like they are forged to me, but I have not really inspected them. They are of course not allowed to ever fail, and that reflects in the current design. My guess is that there is a safety factor of at least 5 on these parts and that a 3D-printed part would do the job just as well as the current parts.
Turbine blades for jet engines are being 3D-printed, I would expect they have some severe requirements for lifetime and safety...

3D printing wishbones would by the cost a fortune due to size, so I would machine them from solid rods instead, if I had to replicate them (and they had to look original...)

 

Cost comparison is to current laser sintered metal printing.

This uses a 1400 degree sintering process which does not use lasers. No toxic outgassing, no toxic dust production.

Metal for the process comes in particle for bound into rods by polymer. It's deposited onto the piece and then heated with traditional hearing elements and also microwaved. This burns out the polymer leaving a very dense ( 99.8% ) metal lattice structure.



They have a prototyping sized unit for $120000. Industrial version too. Next cheapest metal printing system is over a million.

As for suitablilty for use on crucial, high-stress applications, I'm no scientist, but I suspect that being able to internally structure metal intentionally rather than pouring molten metal will lead to parts that are lighter, more durable and superior to those that are cast traditionally. But I'm not saying this device meets that expectation.

Forging is another thing altogether. I've no idea if this tech will grow to compete with that somehow.

 

I think the front wishbones are just cast and then cleaned up. The surface is too rough for a forged surface...

 

I am pretty sure the wishbones are forged Daim; but not certain. Almost all solid wishbones of this era on Uk cars were forged. They are for sure not just untreated castings. I think they are like the driveshafts, which I believe were also forged.

On most modern cars now the wishbones are pressed and welded metal sheet fabrications quite a few mm thick, if my Ford Mondeo is anything to go by. Modern jaguars use forged aluminium suspension arms.
Greg

 

Ot is rather hard to twll, though as the front lower wishbones are rather flexible, they might actually be forged. If considered like that.

My old Volvo C30 had cast aluminium wishbones at the front and pressed sheet steel ones at the rear... Basically the Ford parts

 

Pretty much all jags main suspension components are forged and have been for years.
On the 3D printing front l have often wondered about printing with a wax as a means to investment/lost wax casting method of one off or very low volume parts.

 

The article is part sales ad however the technology is the next big thing, I've been following it closely and between the number of old cars my brother and I tinker with we've seriously considered a higher end consumer grade plastic 3D printer because finding obscure 70s plastic parts for BMWs (and Jag) is damn near impossible. I'm running out of donor cars...

Would be nice to have an inventory of scanned parts for the older cars just to have a permenant digital reference for future printing. That being said the day this can print me a leafspring for my truck and not snap under the weight of a 5000lb pallet being loaded in the box I'll buy the printer in cash.