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Piston engine: how to make a piston start (just read the full thing it's simpler...)

10.3k MethaManAerospace  5.4 years ago

How to make a piston start extended BUT extend even more on throttle (and cycle)...

I'm back at making piston engines but this time doing it properly (well, everything is relative) and I need two pistons that start half way but one pushes and the other pulls...

ill post a link to the test bed if people want...

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    34.9k WarHawk95

    @MethaManAircraft Je te conseille le com d'en dessous

    5.0 years ago
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    @WarHawk95 cimer! au fait, t'as une idee pour resoudre le probleme?

    5.0 years ago
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    5,434 CDRxavier

    @MethaManAircraft
    Because you mentioned about pistons that started half way ...
    can't you stack pistons? (like, one extended on top of one retracted)
    this way, if you want to retract you retract the first one, and when you want to extend you extend the last one.
    It's doable with inputs that have negative values (eg. yaw, pitch, VTOL, Trim) but throttle ... you may need some modding.

    +2 5.3 years ago
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    @CDRxavier Thanks btw

    +1 5.3 years ago
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    @CDRxavier I know, but, the reason why I need this is to be able to make more complicated V8, V6, and V12 engines which need specific angles to 1 be realistic and 2 run smoother... pity...

    +1 5.3 years ago
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    5,434 CDRxavier

    I mean, the X rotary from Visify seem to work without a engine starter ... and my Xenodash too.
    In fact most engine will work without a starter, but it will be difficult to start it (and it put a lot of stress on the parts) and the direction will be in question.

    Currently, the most successful piston engine in my collection is the +-12 (3 pistons on 4 arms oriented 90 degrees apart)
    Like, THE most successful.
    It may generate a lot of torque, but I use them in tandeems anyway. (whether it is a traditional two-engine like Beach King or a radical one like the 335 Pfeil). Depends on rotor size they give around 10 hp to 400 hp.

    The piston engine also gives this unique "pulse" of spin where the rotation speed at the limits (low and high) of the piston (the dead zone) are turned slower (because fixed piston speed)

    So ...
    Just go with starters, just be creative with not using a electric motor (or using hands to push-start the propeller)

    5.3 years ago
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    5,434 CDRxavier

    @MethaManAircraft
    Uh ....
    I know there are pistons that behave like that ...
    So they begin at, say, 30%.
    But they can't go back (below 30%)
    I understand what you are thinking. You are trying to orient the engine (or pistons) so the pistons don't start off at the "dead-position".
    Well, for what I believe (and know), no piston engines on the planet earth works without a starter. So you may as well stick to that. (think cars and propeller planes and boats)
    But as I had demonstrated before, making a engine starter is very very easy. Maybe a combo that drives a stick to push the engine a bit or whatever.

    On the other hand, I have quite some success with bullet-driven propellers, but experience told me that if I want to combine that with a piston engine then things may start to fly apart very quickly

    5.3 years ago
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    23.4k marcox43

    @MethaManAircraft have the same trouble... actually thought of the activation grop idea before, but never put it to use. you should give it a try!

    +2 5.3 years ago
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    @iwanabeelected ?

    5.3 years ago
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    @marcox43 @CDRxavier @KeX0609 any ideas

    +1 5.3 years ago
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    @WNP78 @Visify any ideas?

    5.4 years ago
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    Np @MethaManAircraft

    5.4 years ago
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    @BlackhattAircraft Thanks!

    5.4 years ago
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    @vcharng well that is it sadly...

    5.4 years ago
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    9,445 vcharng

    Yeah I thought about that too, that's why I didn't make my own piston engine...
    Perhaps you can try using 2 pistons in place of one?
    one starts extended, the other retracted, and give them different activation groups, so you extend the 2nd piston, and activate the 1st after full extension.

    but this is not gonna work if you're making a V8 or other complicated piston builds...

    5.4 years ago
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    34.9k WarHawk95

    Tiens, de nouveau actif ?
    Plus sur Discord en tt cas... 😆

    5.4 years ago