Introduction: Creating 3D Printed, Wind-up, No Assembly Required Gadgets

I've recently been working on, no assembly required 3d printed wind-up cars and have been using Shapeways strong and flexible plastic (SLS printer) to print them (i don't have a 3d printer).

In this Instructable I will go through how to design your own 3d printed wind-up gadget as well as giving you some files (including STLs) to help you get started - including a very simple pull back car that you might be able to print in one piece on an extruder-type printer using supports (serious points to you if you manage to get it working!).

Step 1: Designing the Spring

I designed the spring using Adobe Illustrator's Spiral tool I then saved it as an SVG and imported it to turn it into a 3D object.

When using the Spiral tool click and hold the ctrl and or alt key and drag (on a PC) to change the number of turns and the shape of the spiral.

The material you use and thickness of the spring will determine how big and how many spirals/how spaced out they are. For Shapeways nylon (WSF) plastic a spring of about 1mm thick was best. I experimented with different numbers of turns in the spring and found a more spaced out spring was better as it allowed you to wind up the spring further (and therefore unwinds longer).

Included below is the STL (Spring.stl) file for a spring, and the SVG files for a solid line (SpringLine.svg) spring and a spring outline (SpringOutline.svg).

Step 2: The Gears

There is about a 4:1 ratio between these two gears you can stack these two gears to increase the input/output ratio (or you could design your own) .

Because of the large distance required between parts for 3D printing you can't (with standard printers) print gears this fine already interlocked, to get around this and to maintain it's 'no assembly required-ness' the gears are printed in place and then slide together to interlock.

The STL file for these gears is below

Step 3: Putting Together Your Gearbox

Depending on what you want your wind-up gadget to do, the complexity of the wind-up gear box will change. I recommend trying to keep it as simple as possible - this will ensure there are less moving parts and therefore less things that could go wrong.

One of the options you have for your wind-up gear box is whether you want to be able to have your spring unwind as soon as you let go or to have a sort of 'catch' to keep the spring wound until you press a button. I designed this 'catch' as simply as I could. A '+' looking arm (which is attached to the top of the primary gear, which is in turn connected to the spring through a shaft) spins as you wind up the spring, clicking past another thin arm (the thin arm is designed to bend a little bit) which is set in place (unable to turn with the + arm). As the spring is let go the + arm will spin back around and hit the thin arm which it will be unable to click pass as a small stick is stopping the the thin arm from bending backwards. To let the spring unwind, you press the thin arm downwards (by pressing the button on top), releasing the + arm.

*shown above is my first working 3D printed wind-up gear box including pictures of it after i dissected it*

*available below is the basic layout in an STL file (WPBasic.zip) - zipped for your convenience*

Step 4: Free-roll Mechanism

If you're designing a wind-up car (or something like that) you'll want to include a free-roll mechanism that will allow the car to roll with it's own momentum once the spring has unwound. You don't have to include this in your design, though if you don't your car will bounce back once the spring has unwound.

In my design this free-roll mechanism is in the front drive wheels. As the axis connected to the gears spins forwards the Z shaped arm (which is connected to the axis and is free to spin inside the wheel) connects with a long thin arm (connected directly to the wheel) pushing the wheel to turn. Once the spring has fully unwound the wheel will continue to spin under the car's momentum. The long thin arm will click past the rounded back of the Z arm and continue to spin. It is important to make this long thin arm flexible so it doesn't offer much resistance when the car is free-rolling.

*Available below is the basic layout of the free-roll mechanism (FreeRoll.stl)*

Step 5: Implementing Your Gearbox

Once you've designed your basic gearbox you can now implement it in whatever gadget you want!

You can add more springs and/or leavers to achieve different actions, but as i said earlier, if you want it to print in once piece, try to keep it simple. Make sure you keep clearances are large enough to allow moving parts (this will also limit the overall complexity of your design).

The above video is of my first 3D printed, no assembly required wind-up toy which you can check out on Shapeways here - (with alterations made to fix a few problems)

You can also check out 3dprint.com's article for more information about my car here

There is also a simpler pull back only version here

I won't be making the files for these cars available for download, but hopefully from this Instructable you should be able to design your own! And i'll be happy to answer any questions you have!

Step 6: Summary

I hope this Instructable helps in designing your own 3D printed wind-up car or other gadget, as i'd love to see growth in this area of 3D printing!

Included below is the STL file for a simple 'spring only' pull back car for you to use. It is untested but i am confident that it will at least work on an SLS printer - it was designed with a extruder- type printer in mind (Though i don't have one, i have had some first hand experience using them) so if you manage to print it out and get it working, i'd love to see it (the spring may be a bit awkward to print out i know).

Side note - a suggestion that was made to me to increase traction of the wheels was to put rubber bands on them. It greatly helps the movement of the car and stops the wheels spinning out on smooth surfaces

This Instructable is entered in the 3D printing competition so if you enjoyed this instrucable please vote for me!

If you have any questions about this Instructable or about about designing your own wind up gadget please just ask!

Comments

author
kondzio29 made it!(author)2015-04-06

I know about "be nice" policy, but... please show me the "no assembly required" part of this instructable? Maybe I missed this part, but I can se that we need to print very single part and then assembly them. When I saw the "no assembly required" i thought of the car that comes assembled right when it comes out the printer ;) It's a great design but the title is misleading.

author
MrSirLRD made it!(author)2015-04-06

Each step is just the components I included in my design, the whole thing is printed out already assembled. The title explains exactly what it is

author
MrSirLRD made it!(author)2015-04-06

My car does come out of the printer in working order in one piece.......

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vaani.lalitya made it!(author)2015-04-05

this is genius!

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MrSirLRD made it!(author)2015-04-06

Thank you!

author
DragonTamer458 made it!(author)2015-04-04

Great design, though it looks like it could use a bit of rubber on the wheels. Perhaps you could just wrap them with a rubber band?

Fantastic work!

author
MrSirLRD made it!(author)2015-04-05

Thank you! - using rubber bands is one of my suggestions at the end

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snoopindaweb made it!(author)2015-04-05

I love that sort of thing since I was a kid with one main street regular was a Jewel merchant & Clock repair He had a small wind-up gear cutting machine with special files & etc. I once left a raspberry about 3-D and He wrote back describing some up-sides. the One that gets Me is re-using any fails crushing the failure and use the same material to have another go.? That's Gold Dust, that is! I have an old metal and plastic V/W Camper Buss / "Smoakey - Pipe" You drag it backward on a smooth surface and point it where You want it to go and let it do so. ~(:-})={>---- ]

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tammasus made it!(author)2015-04-04

Excellent printing! How do you design the gears?? Is there a specific software so the different gear sizes can interlock appropriately?

author
MrSirLRD made it!(author)2015-04-04

There are a few different ways and softwares to design gears with. I designed these gears from a drawing, it was a rather long, messy and ad hoc method which is why I didn't include it (though it worked in the end). Check out this instructable for better methods https://www.instructables.com/id/3D-models-of-gears-for-3D-printing

author
tammasus made it!(author)2015-04-04

Thanks for your help!

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starforest made it!(author)2015-04-04

Very helpful! I would love to make something wind-up.

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MrSirLRD made it!(author)2015-04-04

It's great fun to play with!

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pseed made it!(author)2015-04-04

really amazing concept, design, and implementation. what software do you use for your design?

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MrSirLRD made it!(author)2015-04-04

I just used 123d design, nothing too complicated

author
Haniyaa made it!(author)2015-04-04

amazing concept. <a title=" love quotes

" href=" http://kquotes.com">
love quotes </a>

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Bio: I like to make everything and anything! from electronics to food! and i'll be showing you all the things i come up with here!
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