# WIP: A combustion Engine

**URL:** <https://discourse.shapr3d.com/t/wip-a-combustion-engine/10633>\
**Category:** Share your creations\
**Created:** [January 1, 2021, 2:05pm UTC](https://discourse.shapr3d.com/t/wip-a-combustion-engine/10633 "2021-01-01T14:05:16Z")\
**Posts on this page:** 4\
**Page:** 1

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**Author:** ![shahmirj](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.shapr3d.com/shahmirj/32/8674_2.png) [@shahmirj](https://discourse.shapr3d.com/u/shahmirj)\
**Post date:** [January 1, 2021, 2:05pm UTC](https://discourse.shapr3d.com/t/wip-a-combustion-engine/10633/1 "2021-01-01T14:05:16Z")

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I wanted to learn (in detail) how a combustion engine works, and I have no tools to build one in parts, so I decided this christmas break to model one.

_Now some caveats: I am a software engineer, so the following is missing a lot of things as it is still a work in progress, but it gets some basics concepts working. Please don’t actually build this it probably won’t work!_

 ![89EF2DC8-77BE-46E2-AED8-9AAA1B230C70](https://us1.discourse-cdn.com/flex002/uploads/shapr3d/original/2X/7/7ba4d203b1b94762f8dafd36ce1000c802cea759.png) ![911A85A6-2C87-4287-B933-583527EC260B](https://us1.discourse-cdn.com/flex002/uploads/shapr3d/original/2X/7/7ba4d203b1b94762f8dafd36ce1000c802cea759.png) ![25070422-2215-473B-97A9-76404B75A0CA](https://us1.discourse-cdn.com/flex002/uploads/shapr3d/original/2X/a/ae63c67e2f37e900fc6ce6a8bd42d2d37ca964b2.png) ![AE77CDA3-B0A4-49AF-8F6B-924D573F8094](https://us1.discourse-cdn.com/flex002/uploads/shapr3d/original/2X/d/d258d7bb9c32c9b8f522b126e82ace5a07cf47d3.png)

From here you can see a few things:

- I improved in making gears (see the yellow one)
- The timing is off, very off :D, I will fix it when I get a chance, but the point is I know how it works
- The exhaust valves are missing the rockers, and cam lobes. WIP
- I learnt about a balancer, so I was thinking of putting that in.
- Clutch/transmission. I might have to get back to my day job and project for the future.

Here are somethings I think Shapr3D really needs:

- **A way to copy, move, repeat**. For example I want to copy a gear tooth, rotated 18 degrees, repeated 19 times (the 20th gear is the source gear).
- **Reflection body** (not sure of the accurate 3d modeling term) where I can build one piston and create a reflection for the subsequent pistons, meaning if I change the master piston the reflected body also changes. Sort of a pointer to the master body. This would have made my life so much easier in a lot of places.
- **icloud/google-drive support** , useful if I can ensure the designs are always in a cloud somewhere. Also I haven’t used the macOS version but being able to switch between the two will definitely be vital.

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**Author:** ![McD](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.shapr3d.com/mcd/32/15504_2.png) [@McD](https://discourse.shapr3d.com/u/McD)\
**Post date:** [January 1, 2021, 3:50pm UTC](https://discourse.shapr3d.com/t/wip-a-combustion-engine/10633/2 "2021-01-01T15:50:37Z")

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Fantastic work! To take it to the next level, look at an App called Jig Workshop. There is a free version, where you can animate individual bodies, as an assembly. That would really be awesome! Take a look at their tutorials. McD

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**Author:** ![MrJack88](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.shapr3d.com/mrjack88/32/8138_2.png) [@MrJack88](https://discourse.shapr3d.com/u/MrJack88)\
**Post date:** [January 1, 2021, 6:59pm UTC](https://discourse.shapr3d.com/t/wip-a-combustion-engine/10633/3 "2021-01-01T18:59:10Z")

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The camshaft timing is the issue  
Where is the second camshaft rod?  
And the camshaft timing have to be little off the crankshaft timing to let combustion chemistry complete.  
You know: explosion, exhaust, inlet.

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**Author:** ![shahmirj](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.shapr3d.com/shahmirj/32/8674_2.png) [@shahmirj](https://discourse.shapr3d.com/u/shahmirj)\
**Post date:** [January 2, 2021, 2:16pm UTC](https://discourse.shapr3d.com/t/wip-a-combustion-engine/10633/4 "2021-01-02T14:16:50Z")

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> [@MrJack88](#):
>
> Where is the second camshaft rod?

Yeah like I said, WIP, I will build it when I get a chance.

> [@MrJack88](#):
>
> And the camshaft timing have to be little off the crankshaft timing to let combustion chemistry complete.

Yep learnt that yesterday in the Haynes manual.