Fully 3D Printed DIY electric car

[_GonZo_]

The Covid let me with no job that lead me to kind of reinventing myself, so while I gather clients for my new designing/engineering consultancy freelance work. I had some time to develop what I find a very cool project: A fully 3D printed vehicle, I called it the Jellybean because its shape reminds to that sweets. And I will like to show it to you, and hope you like it.

The Jellybean3D is a fully DIY Open Source 3D printed electric vehicle.

It is Designed to be made with standard hobby printers and easy to find/work PLA, and/or maybe PETG plastic. Some small parts printed with Nylon. And some off the shelf components like motor, battery, lights, screws, etc.

This is an experimental project that aims to explore the limits of hobby 3D printing.
This project does not aim to reproduce a standard vehicle construction. Many things can go wrong, but I am sure we will enjoy and learn through the process.

I am making some videos about the project progress, construction, info, etc.: https://www.youtube.com/playlist?list=P ... rBmsbD77oQ
[youtube]umWhtFFmUe0[/youtube]

Any suggestion, help, contribution is really welcome.

[LeftieBiker]

Roof, or at the very least, a roll bar and rag top.

[goatman]

that looks like a velomobile, i really like where you going with this
are you going to incorporate channels in the belly pan for something like bolting square aluminum tubing for strength?

any idea on the weight of all the plastic shell?

[The Toecutter]

Interesting project.

What kind of frame is supposed to be underneath the body? If it is a plastic frame as well, I wouldn't trust the car to hold together going down a road. Hopefully there is some kind of metal chassis.

Any target curb weight considered yet?

How many hours do you expect it would take to glue all of these pieces together?

What software did you use to design it?

I'd like to use a 3D printer to make a velomobile, an electric velomobile, and an ultralight < 300 lb electric one-seater sports car using a modular platform shared in common between the three. 3D printing the body work will save a LOT of labor. A friend and I discussed the same technique that you are using, but I think he's underestimating the labor requirement.

I'm impressed with the initial progress posted so far as well as the design. Thank you for posting this!

[_GonZo_]

Roof, or at the very least, a roll bar and rag top.

Yes, that will be really great. But I have not find a nice way to do it.
Any suggestion, drawings, examples will help if you have any.

Answers to other posts latter, family calling for lunch...

[_GonZo_]

that looks like a velomobile, i really like where you going with this
are you going to incorporate channels in the belly pan for something like bolting square aluminum tubing for strength?

any idea on the weight of all the plastic shell?

Thank you Goatman.

See picture from the bottom, I added 2 aluminium "brackets" that go screwed and glued to the unibody. And there is some other aluminium brackets on key places to withstand and distribute stress.

About the weight I only have an estimations so far:
Weight estimation for 3D printed parts is around 35 to 45Kg (It will vary depending on the material/s chosen and printing profiles)
In a few days (maybe weeks) will have more accurate number.

[Dauntless]

Rollbar. Very important that you remember it has to be attached to something underneath that doesn't give way. For a space frame you have SCCA regulation 1 5/8" last time I looked for the outside diameter, .95" thickness tube. That would run under the driver then an upright is attached for your roll bar. great for 100 mil an hour flips, but not perfect.

From my childhood, I vaguely remember they thought the rear upright of the old Porsche 914 would be plenty safe for club racing, leading to the painful discovery it wasn't. Did it hold up in freeway accidents? I don't know, but then the normal car roof doesn't survive without a roll cage inside. You only need good enough for maybe 25mph, right?

I think the cage will probably have to wrap around outside. A diagonal on each side protects from getting t-boned. That first one only needs to cross members underneath joining it, right?

[_GonZo_]

What kind of frame is supposed to be underneath the body? If it is a plastic frame as well, I wouldn't trust the car to hold together going down a road. Hopefully there is some kind of metal chassis.

Any target curb weight considered yet?

How many hours do you expect it would take to glue all of these pieces together?

What software did you use to design it?

I'd like to use a 3D printer to make a velomobile, an electric velomobile, and an ultralight < 300 lb electric one-seater sports car using a modular platform shared in common between the three. 3D printing the body work will save a LOT of labor. A friend and I discussed the same technique that you are using, but I think he's underestimating the labor requirement.

Thank you Toecutter for your comments.
Answering to your questions:

• It is a self supported structure, with the add of different aluminium brackets on key areas in order to reinforce and distribute stress. (see section picture of the vehicle)

• Estimated Vehicle weight 75 to 85Kg, Final weight may vary depending on printing material/s, printing profiles and components chosen.

• Estimated printing time 500 to 600h

• In a few days (maybe weeks) will have more accurate numbers

• Onshape

The idea of using a standard vehicle chassis frame plus a 3D printed body is a solution that works quite well. It will save you time on building but designing it provably takes longer, as you need the full body designed in 3D CAD. While if you are just shaping foam and fibreglass/carbon with some hand draw sketches may be enough... Please share your idea with us.
There is already some good examples of that method, I have collected a few examples in the first video I made about this project: https://youtu.be/umWhtFFmUe0
[youtube]AGlTigpCbPU[/youtube]

[The Toecutter]

Thank you Toecutter for your comments.
Answering to your questions:

• It is a self supported structure, with the add of different aluminium brackets on key areas in order to reinforce and distribute stress. (see section picture of the vehicle)

• Estimated Vehicle weight 75 to 85Kg, Final weight may vary depending on printing material/s, printing profiles and components chosen.

• Estimated printing time 500 to 600h

• In a few days (maybe weeks) will have more accurate numbers

• Onshape

Thank you for those answers. I'm curious to see how well this design holds up to use.

Please share your idea with us.

I eventually will. My designs were done up in a notebook with a pencil, but I haven't been able to get my mother's scanner working with which to get them into a format that can be shared. They are also tentative and subject to be changed anyhow. Only two of them were actually made, both of them velomobile bodies for my front-suspension KMX trike, and another third one is a work in progress, a 3-wheeled car that a friend of mine has been putting together. I have designs other than those 3, but I do not know if they will ever become reality.

[LeftieBiker]

The easiest way around not having a scanner is to use a smartphone to take a photo of the sketch, then email it to yourself.

[_GonZo_]

Rollbar. Very important that you remember it has to be attached to something underneath that doesn't give way. For a space frame you have SCCA regulation 1 5/8" last time I looked for the outside diameter, .95" thickness tube. That would run under the driver then an upright is attached for your roll bar. great for 100 mil an hour flips, but not perfect.

You only need good enough for maybe 25mph, right?

I think the cage will probably have to wrap around outside. A diagonal on each side protects from getting t-boned. That first one only needs to cross members underneath joining it, right?

Thank you for your input Dauntless, as you stated I am not planing racing with it, I will be only doing some in town commuting and I plant to limit it around 45-50Km/h (+-30mph). I was not planing using any kid of roll bar. But the idea of adding one wrapping outside can be very good if at the end the self support structure is not strong enough. Thank you.

[Balmorhea]

3D printing is the hot glue gun of early 21st century males. Like late 20th century females with their hot glue guns, once they grasp the basics of the technology, they stop thinking about whether it's appropriate to the job at hand. They use it in whatever situation, regardless.

In both cases, these techniques frequently constituted an impediment to learning more suitable methods.

[Dauntless]

In both cases, these techniques frequently constituted an impediment to learning more suitable methods.

Sounds like a master's thesis on why there are so few female engineers.

Meanwhile, it's about a fun project he can pull off. Such as when they were teaching us at the community college to make things out of cardboard such as bridges, chariots for a 'Ben-Hur' race, etc. It's a staple at universities to have the cardboard canoe race. It's fun, semipractical, maybe something good can even come of it.

Before my accident a few years ago I was cutting out the pieces for this to make it out of cardboard. Well, it's a honeycomb core of cardboard with fiberglas slab sides.

https://struckcorp.com/older_products/m ... 0-2wd-4wd/

I wish I had all the parts laying around the way this guy does.

[youtube]_d2WkjrAi2A[/youtube]

[The Toecutter]

Is that a 1000W front-drive Leafbike motor in a 20" cast wheel in the rear?

I would not trust PLA, PETG, or Nylon as a material composing a self-supporting structure to hold up to the vibrations and mechanical stresses that such a vehicle is going to be subjected to, at least not for any appreciable length of time. Your vehicle's lifespan may be measurable in tens or hundreds of miles if you actually end up operating it over rough pothole-laden roads.

IMO, it needs a steel or aluminum frame underneath that attaches to the suspension mounts, or it's going to rip itself apart and/or fall apart.

But then again, maybe you've done the math(or had a program do the math) on it and determined it will work. If you have, make sure you have mitigation techniques to prevent UV radiation, harmonics, torsional forces experienced while cornering/braking, temperature extremes, and the like from changing your build material's initial properties and destroying your hard work or causing a catastrophic failure while you are operating it.

I'm sure it's only going to be a small number of components in your design that prove to be the weak links. When you discover what they are, you will be able to revise the design with revised versions of them made out of a more suitable material.

This all said, this project is cool as hell.

The easiest way around not having a scanner is to use a smartphone to take a photo of the sketch, then email it to yourself.

I don't own a smartphone, and when I did try this technique with the phone of another, my pencil lines did not show very well in the image.

[_GonZo_]

3D printing is the hot glue gun of early 21st century males. Like late 20th century females with their hot glue guns, once they grasp the basics of the technology, they stop thinking about whether it's appropriate to the job at hand. They use it in whatever situation, regardless.

In both cases, these techniques frequently constituted an impediment to learning more suitable methods.

I agree with you Balmorhea, I know there is some people that thinks that everything can be done with 3D printers. I am not one of them.
A 3D printer is just another tool, with great capabilities but just one of many that we can use.
This project as stated is an experimental project that aims to explore the limits of hobby 3D printing, nothing else.
I am very aware that there is better ways to build a vehicle like this. But, been there done that.

[_GonZo_]

I wish I had all the parts laying around the way this guy does.

I wish that as well, I have to find and buy them like anyone else.

[_GonZo_]

Is that a 1000W front-drive Leafbike motor in a 20" cast wheel in the rear?

I would not trust PLA, PETG, or Nylon as a material composing a self-supporting structure to hold up to the vibrations and mechanical stresses that such a vehicle is going to be subjected to, at least not for any appreciable length of time. Your vehicle's lifespan may be measurable in tens or hundreds of miles if you actually end up operating it over rough pothole-laden roads.

But then again, maybe you've done the math(or had a program do the math) on it and determined it will work. If you have, make sure you have mitigation techniques to prevent UV radiation, harmonics, torsional forces experienced while cornering/braking, temperature extremes, and the like from changing your build material's initial properties and destroying your hard work or causing a catastrophic failure while you are operating it.

I'm sure it's only going to be a small number of components in your design that prove to be the weak links. When you discover what they are, you will be able to revise the design with revised versions of them made out of a more suitable material.

Thank you again Toecutter for your inputs.
- Plan to use a 1000-1500W motor.
- Yes, PLA, PETG, plastic in general is probably not the best material to make a self supporting structure like this. They have been chosen because they are easy to find and easy to print, not because I may think are the best for the application.
- I will try to take good care of it in order to make it live long.
- Made the maths and no problem on the overall, the problems are going to be that small number of weak links, components and details you talk about...

[_GonZo_]

I just created a project in Prusa printers and Thingiverse because I will be releasing the Open Source in a few days (maybe weeks…) and needed the links for the documentation.
And because in some forums people wanted to see more and see how the parts are, and if they can print them.
So I just uploaded in the projects a couple samples pieces of the body, anyone can print them with the printing suggestions and profiles detailed and check if they like the idea.
Please post your prints and please give some feedback.

Link to PrusaPrinters: https://www.prusaprinters.org/prints/46 ... ellybean3d
Link to Thingiverse: https://www.thingiverse.com/thing:4667329
Any suggestion and help is welcome. Feel free to comment.

[goatman]

the first thing i thought when i saw what you were doing was, fiberglass mold

trying to enclose the belly of a trike is a PIA, just being able to print off the belly pan as a platform to build off would be awesome

[_GonZo_]

trying to enclose the belly of a trike is a PIA, just being able to print off the belly pan as a platform to build off would be awesome

Make a belly pan for a trike with 3D printed parts it is very feasible as I suppose that it does not need to support big stresses. But probably to design it maybe difficult.
What means PIA?

[The Toecutter]

PIA is an acronym for "Pain In the Ass".

[markz]

Or PITA and not the food

[LeftieBiker]

PIA is an acronym for "Pain In the Ass".

That would be "PITA" - one of the less common acronyms in which the word "the" is included.

[_GonZo_]

I made a printable 1/10 scale model of the Jellybean3D.
You can download the file parts for printing from: https://www.prusaprinters.org/prints/47678
Check this short video for printing, assembly instructions and other details: https://youtu.be/9_9_ydc-NO4

[youtube]9_9_ydc-NO4[/youtube]

[_GonZo_]

The printing files can be downloaded as well now from Thingiverse: https://www.thingiverse.com/thing:4669754