Towards the *fully* 3D-printed electric car

[RobertGC]

An article from 2015:

3-D-printed car could hit streets next year. Chris Woodyard, USA TODAY 4:48 p.m. EST November 12, 2015
http://www.usatoday.com/story/money/cars/2015/11/10/3d-printed-car-local-motors-swim/75530830/

Several companies have come out with what they call "3D-printed" cars, but none have 3D-printed the most important part, the engine.
This would be difficult to do with an internal combustion engine, with its high temperatures, multiple moving parts, and high tolerances.
But it shouldn't be too difficult with an electric engine. In fact considering there are now miniature 3D-printers on the market for the home, an amateur could be the first to produce an entire, scale-size, 3D-printed car. And then it could be scaled up to produce a full-size, working, fully 3D-printed automobile.
This would revolutionize the industry, obviously.
The two most difficult parts would be the engine and the transmission.
This video shows how you can make your own simple electric motor:

How to Make an Electric Motor at Home - YouTube.


Looking at the steps in the video, it appears they could all be accomplished by 3D-printing.

Bob Clark

 

[Mech_Engineer]

But it shouldn't be too difficult with an electric engine. In fact considering there are now miniature 3D-printers on the market for the home, an amateur could be the first to produce an entire, scale-size, 3D-printed car. And then it could be scaled up to produce a full-size, working, fully 3D-printed automobile.

This would revolutionize the industry, obviously.

Your arguments do not logically follow each other; the technologies involved in consumer Fused Deposition Modeling (FDM) 3D printers are miles different than Direct Metal Laser Sintering (DMLS) processes. DMLS requires very expensive machinery ($300k+) that sinters parts using a powerful laser in an inert gas environment; home 3D printers squeeze melted plastic out of a nozzle like a hot glue gun.

I see no obvious path towards a fully 3D printed vehicle as you claim. Do you have any examples of a printing process capable of "printing" a functioning electric motor? Even just the rotor or stator?

 

[JBA]

Metal power deposition printing and successive sintering (a modified method of creating essentially powder metal parts) currently performed by a number of 3D printing companies should be an easy method for creating the required electric motor core and body components but would not eliminate the need for the copper wire windings and possibly not the motor shaft. No gear system required for 4 wheel direct motor drive systems but gears have been produced by the same method.

 

[RobertGC]

Your arguments do not logically follow each other; the technologies involved in consumer Fused Deposition Modeling (FDM) 3D printers are miles different than Direct Metal Laser Sintering (DMLS) processes. DMLS requires very expensive machinery ($300k+) that sinters parts using a powerful laser in an inert gas environment; home 3D printers squeeze melted plastic out of a nozzle like a hot glue gun.

I see no obvious path towards a fully 3D printed vehicle as you claim. Do you have any examples of a printing process capable of "printing" a functioning electric motor? Even just the rotor or stator?

You are correct that metal 3D-printed parts by amateurs were only designed by them, but had to be actually printed by one of the large 3D-printing companies.

Still, that leaves open the possibility that a scale-model car could be designed by amateurs to be fully 3D-printed by one of the large companies.

The largest of the professional, metal 3D-printers common now can 3D-print parts about a foot across and cost about $250,000. So you can imagine a 3D-printer that can 3D-print parts, say, 10 feet across, would be 10³ = 1,000 times larger in volume and mass, and perhaps a thousand times more expensive, to $250 million.

An expensive proposition. But if it can be shown a scale-model car can be fully 3D-printed then it might be worthwhile for a large industrial company to invest in this when it would mean any car of any model could be 3D-printed on demand.

Bob Clark

 

[RobertGC]

Metal power deposition printing and successive sintering (a modified method of creating essentially powder metal parts) currently performed by a number of 3D printing companies should be an easy method for creating the required electric motor core and body components but would not eliminate the need for the copper wire windings and possibly not the motor shaft. No gear system required for 4 wheel direct motor drive systems but gears have been produced by the same method.

Yes, this is the method that could most easily be copied by amateurs for 3D metal printing since it similar to the method used now by amateurs for doing plastic 3D-printing:

Desktop Metal Production System.


The only complication is that it is a 3 step process: the part is 3D printed, then put in a solvent bath to dissolve the binder, then finally put in a high temperature oven to sinter the metal together.

However, the method itself probably is not patented since another company Metal X is using the same process:

Solid Metal 3D Printing Under $100k - Markforged Metal X | CES 2017.


Many amateurs working independently could come up with improvements to the process.

For instance, is it possible to combine the metal deposition, dissolving the binder, and sintering all into a single step?

Bob Clark

 

[RobertGC]

Metal power deposition printing and successive sintering (a modified method of creating essentially powder metal parts) currently performed by a number of 3D printing companies should be an easy method for creating the required electric motor core and body components but would not eliminate the need for the copper wire windings and possibly not the motor shaft. No gear system required for 4 wheel direct motor drive systems but gears have been produced by the same method.

Ideally, you would want the entire car to be 3D printed, but you could have most of the electric motor be 3D printed and the core wire windings placed separately.
The method of metal powder deposition printing, most similar to the method amateurs use for plastic 3D-printing, would be difficult to create also the wire windings at the same time as the electric motor. The reason is it requires an additional step of heating at high temperature and the wire insulation would melt. Perhaps there could be used high temperature ceramic coating for the wires.

Other methods for 3D-metal printing such as electron beam and laser deposition do not require this extra step of furnace heating so should be able to do the copper wire winding, assuming the 3D-printer has the capability of rapidly switching out the material being deposited between metal and plastic as needed. For instance if you imagine a horizontal slice through the electric motor. You would have wire insulation, then the copper wire, then insulation, then copper wire, and this pattern would be repeated, then you would have the core, then the insulation, copper pattern repeated again. A 3D-printing method that could rapidly switch between metal and plastic insulation material should be able to do this.

Bob Clark

 

[RobertGC]

Metal power deposition printing and successive sintering (a modified method of creating essentially powder metal parts) currently performed by a number of 3D printing companies should be an easy method for creating the required electric motor core and body components but would not eliminate the need for the copper wire windings and possibly not the motor shaft. No gear system required for 4 wheel direct motor drive systems but gears have been produced by the same method.

Direct drive systems do not require gears? I was not aware of that. I would think gears or some method of "mechanical advantage" would always need to be used to match the motor speed to the speed of the vehicle.

Bob Clark

 

[russ_watters]

You are correct that metal 3D-printed parts by amateurs were only designed by them, but had to be actually printed by one of the large 3D-printing companies.

Still, that leaves open the possibility that a scale-model car could be designed by amateurs to be fully 3D-printed by one of the large companies.

I don't think you heard his objection. It doesn't have anything to do with scale and doesn't even primarily have to do with the different methods used, its that there are no methods in use or even in development that can create the key parts (the moving parts, wiring and electronics. There is no path currently in development that comes anywhere close to a fully 3D printable car on any scale.

Ideally, you would want the entire car to be 3D printed...

Why? Why is this a desirable goal?

Other methods for 3D-metal printing such as electron beam and laser deposition do not require this extra step of furnace heating so should be able to do the copper wire winding, assuming the 3D-printer has the capability of rapidly switching out the material being deposited between metal and plastic as needed. For instance if you imagine a horizontal slice through the electric motor. You would have wire insulation, then the copper wire, then insulation, then copper wire, and this pattern would be repeated, then you would have the core, then the insulation, copper pattern repeated again.

Your description of the complexity level is overly simplistic and even then there is no such technology on the drawing board.

To repeat: there is no currently active technology development path that ends in a fully 3D printable car.

...and not for nothing, but the OP reads like a failed attempt at bait and switch: we can't 3D print a gas engine, so let's switch to an electric motor which...er... we also can't 3D print!

To be frank, there is considerable usefulness with 3D printing, but right now it seems to me like its scifi/fad value is swamping its actual value.

 

[russ_watters]

Direct drive systems do not require gears? I was not aware of that. I would think gears or some method of "mechanical advantage" would always need to be used to match the motor speed to the speed of the vehicle.

The term "direct drive" means no gears (or pulleys). The reason gas cars have gears is:
1. They have one engine and have to power at least two wheels. Electric motors can be placed at each wheel.
2. They have a limited range of RPM where they function well. Electric motors produce about the same torque at any RPM.

 

[NTL2009]

RobertGC said: ↑
Ideally, you would want the entire car to be 3D printed...

Why? Why is this a desirable goal? ...

Exactly. This is what I call "Falling in love with a technology". That approach doesn't help us, we should be technology agnostic, and look to results. Why would we want a car to be 3-D printed? Why?

3-D printing can be a great approach in certain cases, generally small production, or custom/semi-custom parts. But anyone who has seen the production speed and low per part cost of metal being poured into molds, or stamped, or plastic blow molding (generally with multiple items produced in one step) should be impressed with how very slow and expensive 3-D printing is in comparison.

Use each technology where it fits. Don't force square pegs in round holes.

 

[256bits]

it might be worthwhile for a large industrial company to invest in this when it would mean any car of any model could be 3D-printed on demand.

Impracticalities abound - financial, economic and technical.
A positive return on investment is what most entities consider very important for the go/no go decision.

It the technicalities were to be overcome, then,
If your cost example of the just the machine of 250M$ is anything to go by, which it may or may not be, if that one machine could perhaps produce one car a week, that's a retail price of 500,000$/car just to re-coup the $ for that one investment with no profit. Add in labour, material cost, plant, and maintenance, operating costs, and profit, then one could be looking at $!M to $2M per car as a wild guess.

Feasibility analysis

 

[HowlerMonkey]

The reason you don't see this happening is that it's just not economically feasible.

Why wear out your million dollar SLM machine making an engine block when it can be cheaply cast.

I also don't see SLM making a crankshaft stronger than forged steel.

 

[RobertGC]

I don't think you heard his objection. It doesn't have anything to do with scale and doesn't even primarily have to do with the different methods used, its that there are no methods in use or even in development that can create the key parts (the moving parts, wiring and electronics. There is no path currently in development that comes anywhere close to a fully 3D printable car on any scale.
Why? Why is this a desirable goal?
Your description of the complexity level is overly simplistic and even then there is no such technology on the drawing board.
To repeat: there is no currently active technology development path that ends in a fully 3D printable car.
...and not for nothing, but the OP reads like a failed attempt at bait and switch: we can't 3D print a gas engine, so let's switch to an electric motor which...er... we also can't 3D print!
To be frank, there is considerable usefulness with 3D printing, but right now it seems to me like its scifi/fad value is swamping its actual value.

As to why, because of the sci-fi dream of just dialing in your vehicle and see it created before you. Got bored with your Porsche? Download the specs on a Ferrari and watch as your home 3D-printer builds up your new Ferrari layer by layer before your eyes and has it ready in a couple of days.

DeskTop Metal says their production level machine will be able to produce multiple metal parts at 8,200 cm³ per hour. With say the steel content of a car at, say, 1,000 kg, 1,000,000 grams, and the density of steel at 7.8 gms/cm³, 1,000,000/7.8 = 128,000 cm³. The DeskTop Metal production level machine could 3D print this in 128,000/8,200 = 15.6 hours.

The DeskTop Metal production machine though only has a manufacturing volume of about a foot across. So this would have to be scaled up for producing large parts. The DM chief engineer says the process could be scaled up to produce something like a car chassis:

VIDEO: How Additive Manufacturing Can Produce Metal Parts en Masse. James
Anderton posted on June 06, 2017.


Bob Clark

 

[RobertGC]

Exactly. This is what I call "Falling in love with a technology". That approach doesn't help us, we should be technology agnostic, and look to results. Why would we want a car to be 3-D printed? Why?
3-D printing can be a great approach in certain cases, generally small production, or custom/semi-custom parts. But anyone who has seen the production speed and low per part cost of metal being poured into molds, or stamped, or plastic blow molding (generally with multiple items produced in one step) should be impressed with how very slow and expensive 3-D printing is in comparison.
Use each technology where it fits. Don't force square pegs in round holes.

Another 3D-printing technique that doesn't use laser sintering has better promise for producing metal parts at high speed:



Bob Clark

 

[jack action]

Got bored with your Porsche? Download the specs on a Ferrari and watch as your home 3D-printer builds up your new Ferrari layer by layer before your eyes and has it ready in a couple of days.

When I'm bored with my Porsche, I go to the Ferrari dealership and get my new Ferrari, at worst, in a couple of days.

So why do I need - at home - a machine larger than a car, that will certainly cost more than the Ferrari itself? And I still have to go out to buy the material and do maintenance on the machine!

Yah, I really hate when I'm printing a car and the process stops with the error message «The copper cartridge is empty.»

 

[RobertGC]

When I'm bored with my Porsche, I go to the Ferrari dealership and get my new Ferrari, at worst, in a couple of days.
So why do I need - at home - a machine larger than a car, that will certainly cost more than the Ferrari itself? And I still have to go out to buy the material and do maintenance on the machine!
Yah, I really hate when I'm printing a car and the process stops with the error message «The copper cartridge is empty.»

Yes. The cost of these machines is high now. But as I said the "binder jetting" method used by Desktop Metal is something that could be copied by amateurs since it is so similar to what they are doing now with plastics. With many amateurs doing the same thing as the commercial machines the price for these machines would come down.

Bob Clark

 

[NTL2009]

As to why, because of the sci-fi dream of just dialing in your vehicle and see it created before you. Got bored with your Porsche? Download the specs on a Ferrari and watch as your home 3D-printer builds up your new Ferrari layer by layer before your eyes and has it ready in a couple of days. ...

Bob Clark

You are just talking rich guy, hobby level "cool wants", nothing with any practicality at all, even for high end cars.

I doubt you have ever worked in high volume manufacturing. The speed and capability of the equipment is incredible. You simply cannot serially lay down material as fast as you can stamp it, die cut it, mold it etc. And you can do things like mold a part, and then do a little CNC machining for the surfaces that require higher precision. It's why we have so many functions on silicon chips now (both electrical and micro-mechanical), those are batch processed in parallel, they don't build them up transistor by transistor. OK, I'm not sure, but they may actually use a light beam to serially move along and outline/define the transistors - in the old days that was a batch light/photo-mask process. But they will batch everything they can.

Will cars have specific parts made with these 3-D printers? Maybe, and most likely for expensive, low-volume or custom cars. But printing the entire car? There is no reason, no motivation for it. No. Not in our lifetimes. And while these technologies advance, so do the competing technologies. Maybe not as fast, but they are so far ahead in so many ways for some of these parts, it's not even comparable.

Again, the right tool for the job. You are trying to shoe-horn a technology in where it doesn't fit. Fine if you want to do that for personal reasons, but no way will I invest in your company if that is your goal!

It's like asking "Instead of reaching into the cabinet and pulling out a glass to get a drink of water, could I have a 3-D printer print a custom design glass for me every time I'm thirsty? And it could remelt the material and recycle it to make the next one!" Well, I suppose you could, but it is a solution looking for a problem.

 

[jack action]

It's like asking "Instead of reaching into the cabinet and pulling out a glass to get a drink of water, could I have a 3-D printer print a custom design glass for me every time I'm thirsty? And it could remelt the material and recycle it to make the next one!" Well, I suppose you could, but it is a solution looking for a problem.

I thought you were going to say it's like asking «Instead of opening a faucet to get water from the municipal aqueduct, you have a "water printer" that builds $H_2O$ from your hydrogen tank.»

 

[russ_watters]

As to why, because of the sci-fi dream of just dialing in your vehicle and see it created before you. Got bored with your Porsche? Download the specs on a Ferrari and watch as your home 3D-printer builds up your new Ferrari layer by layer before your eyes and has it ready in a couple of days.

...Yes... With many amateurs doing the same thing as the commercial machines the price for these machines would come down.

That's what I figured. Please don't confuse sci-fi dreams with technical and economic realities. This is a technical forum, not a sci-fi forum and posting a sci-fi dream on a technical forum does not make it technically or economically (or legally) possible.

 

[JBA]

Production cars (US) and trucks (Daimler) already have 3D printed parts. As described in an earlier post, GE's gas turbine division acquired two 3D companies that it is now using to print parts of it gas turbine engines and they have been able to replace 35 suppliers with just those two 3D sources, as reported by a GE Division executive in a presentation speech.
Daimler is now expanding their 3D printing by placing machines at their spare parts supply centers for providing 24 hr delivery of replacements for their 3D printed parts.
One US auto manufacturer (I believe it is GM but I do not have the sources material to check) has also installed a large volume 3D machine in their design division to replace the full clay models of their prototype body designs.
The idea of using 3D printing for a complete car is not necessarily a practical idea but many corporations are already deep into this technology.

 

[RobertGC]

That's what I figured. Please don't confuse sci-fi dreams with technical and economic realities. This is a technical forum, not a sci-fi forum and posting a sci-fi dream on a technical forum does not make it technically or economically (or legally) possible.

The chief engineer of Desktop Metal says their industrial production machine due to be introduced next year could be scaled up to produce a car chassis:



He says it will already be able to produce multiple copies of small metal parts at costs comparable to those for a commonly used production process of metal injection moulding.

Injection moulding.
Injection moulding BrE or Injection molding AmE, is a manufacturing process for producing parts by injecting material into a mould. Injection moulding can be performed with a host of materials mainly including metals, (for which the process is called die-casting), glasses, elastomers, confections, and most commonly thermoplastic and thermosetting polymers. Material for the part is fed into a heated barrel, mixed, and forced into a mould cavity, where it cools and hardens to the configuration of the cavity.[1]:240 After a product is designed, usually by an industrial designer or an engineer, moulds are made by a mould-maker (or toolmaker) from metal, usually either steel or aluminium, and precision-machined to form the features of the desired part. Injection moulding is widely used for manufacturing a variety of parts, from the smallest components to entire body panels of cars.
https://en.wikipedia.org/wiki/Injection_moulding

This suggests likewise when scaled up it could produce large metal parts such as car body panels at a competitive price.

Bob Clark

 

[NTL2009]

...

This suggests likewise when scaled up it could produce large metal parts such as car body panels at a competitive price.

Bob Clark

I disagree. This is a sales pitch from a company rep. What it suggests to me is that they are promoting their product. Show me some current independent third party measurements and analysis - those will "suggest" something.

They may have a very good product that will extend the "reach" of 3-D printing. I'm highly skeptical that this will replace the other methods to the extent you dream about. I asked earlier - have you ever worked in high volume production (I have)?

 

[RobertGC]

I disagree. This is a sales pitch from a company rep. What it suggests to me is that they are promoting their product. Show me some current independent third party measurements and analysis - those will "suggest" something.

They may have a very good product that will extend the "reach" of 3-D printing. I'm highly skeptical that this will replace the other methods to the extent you dream about. I asked earlier - have you ever worked in high volume production (I have)?

I agree it may be sales hype. Their production machine is due to be introduced in 2018. So we'll be able to tell within a year if the reality matches the hype.

Bob Clark

 

[Rx7man]

If you look just at the metallurgy of the gears, shafts, bearings, etc and the heat treating, plating, and hard surfacing processes involved, you will immediately see that 3D printing can make the part in the shape it needs to be, but it won't have the characteristics it needs.

3D printing is great for things which are impossible to cast or form due to their geometry, or for prototypes and small batch runs. For pretty much everything else, there is a process available that is far faster, more accurate, and more affordable

 

[RobertGC]

GE has mass produced via 3D-printing a metal nozzle tip that would have been difficult to produce using other methods:

An Epiphany Of Disruption: GE Additive Chief Explains How 3D Printing Will Upend Manufacturing. Jun 21, 2017 by Tomas Kellner
The nozzle met the team’s wildest expectations. Morris’ machine not only combined all 20 parts into a single unit, but it also weighed 25 percent less than an ordinary nozzle and was more than five times as durable. “The technology was incredible,” Ehteshami says. “In the design of jet engines, complexity used to be expensive. But additive allows you to get sophisticated and reduces costs at the same time. This is an engineer’s dream. I never imagined that this would be possible.”
http://www.ge.com/reports/epiphany-...xplains-3d-printing-will-upend-manufacturing/

But what I really find interesting in this article are some comments GE's additive manufacturing head Ehteshami said about what he see's for the future of 3D-printing:

“I was excited but also disturbed,” says Mohammad Ehteshami after a vendor printed an complex part for a jet engine. “I knew that we found a solution, but I also saw that this technology could eliminate what we’ve done for years and years and put a lot of pressure on our financial model.”

and:

Ehteshami calls his additive awakening an “epiphany of disruption.” Says Ehteshami: “Once you start thinking about it, you realize both intellectually and emotionally ‘Oh my God, if I don’t start moving, somebody else will.’ You are excited because you are an engineer, but you are also afraid because you are a human being. Both of these feelings start pulling at you to say: ‘I’ve got to go, I’ve got to go.’ And you start running.”

From the way I interpret what Ehteshami is saying, it mirrors something I've been thinking. You can imagine not just cars being fully 3D-printed, but entire airplanes, tractors, construction vehicles, refrigerators, air conditioners, and everything else called "durable goods". But this would mean nearly all manufacturing jobs would be replaced by 3D-printing machines. That is a major economic disruption.

Not only that, but all these would become much cheaper. Would the companies that produce them even be billion dollar companies anymore?

Bob Clark

 

[NTL2009]

GE has mass produced via 3D-printing a metal nozzle tip ...

I don't think many people would consider turbine engines for power plants as being "mass produced". They are very large, multi-million dollar machines with very specific uses and set of working conditions.

... From the way I interpret what Ehteshami is saying, it mirrors something I've been thinking. You can imagine not just cars being fully 3D-printed, but entire airplanes, tractors, construction vehicles, refrigerators, air conditioners, and everything else called "durable goods". But this would mean nearly all manufacturing jobs would be replaced by 3D-printing machines. That is a major economic disruption.

... Not only that, but all these would become much cheaper. Would the companies that produce them even be billion dollar companies anymore?

Bob Clark

I think you are reading far too much into this. Maybe you can imagine all those things being 100% 3-D printed, I can't. And it's not due to lack of imagination on my part, it's due to having some experience in both high-volume manufacturing, and one-off, or limited run prototyping. They are different worlds. And there is no basis to say all those things would be cheaper if they were 100% 3-D printed. It is much more reasonable to think they will be cheaper with some parts 3-D printed, and other parts made by whatever process is best suited for the part. It's not one-size(method)-fits-all.

I agreed with you earlier that 3-D printing will very likely extend its reach into more areas as it improves. That's how most useful technology advances. But that doesn't mean it replaces every existing technology 100%.

 

[russ_watters]

But what I really find interesting in this article are some comments GE's additive manufacturing head Ehteshami said about what he see's for the future of 3D-printing:

“I was excited but also disturbed,” says Mohammad Ehteshami after a vendor printed an complex part for a jet engine. “I knew that we found a solution, but I also saw that this technology could eliminate what we’ve done for years and years and put a lot of pressure on our financial model.”

and:

Ehteshami calls his additive awakening an “epiphany of disruption.” Says Ehteshami: “Once you start thinking about it, you realize both intellectually and emotionally ‘Oh my God, if I don’t start moving, somebody else will.’ You are excited because you are an engineer, but you are also afraid because you are a human being. Both of these feelings start pulling at you to say: ‘I’ve got to go, I’ve got to go.’ And you start running.”

From the way I interpret what Ehteshami is saying, it mirrors something I've been thinking. You can imagine not just cars being fully 3D-printed, but entire airplanes, tractors, construction vehicles, refrigerators, air conditioners, and everything else called "durable goods". But this would mean nearly all manufacturing jobs would be replaced by 3D-printing machines. That is a major economic disruption.

Ok, that's enough. Ehteshami most absolutely does *not* say anything of the sort. I thought previously I'd gotten you to recognize/acknowledge that printing an entire machine is not a an idea that is on any drawing board anywhere, but I guess I was wrong. This is not a forum for discussing fantasy. Thread locked.

 

[russ_watters]

Postscript, because I can:

And there is no basis to say all those things would be cheaper if they were 100% 3-D printed. It is much more reasonable to think they will be cheaper with some parts 3-D printed, and other parts made by whatever process is best suited for the part. It's not one-size(method)-fits-all.

Agreed. In particular, nozzles and other parts with complex internal geometries can be made cheaper largely because they have fewer total parts: 18 vs 1! ( http://www.geglobalresearch.com/innovation/3d-printing-creates-new-parts-aircraft-engines ). That might not be exciting compared to a garage that prints you a new car every day, but to an engineer it is practically Earthshattering. And this would have been the basis for a nice thread. It's too bad.