Oh, of course, the tree! To be honest I haven't looked to see where the Mass block fits into that yet.
It's not critical anyway. You can always add it in later if you decide you want to try it out.

Okay thanks, can't build artificial mass right now because of the survival tech tree. I'll use the vehicle without that.

Oh... and it's completely optional. You don't need to build it if you don't want to. The truck will work fine without it.

The Ariticial Mass block will be especially useful to you on the moon.
It wont work in natural gravity but if you're driving around inside of an artificial gravity field, turn the Mass block on & it'll make the truck behave as if it has slightly more mass.
It basically helps to keep the truck on the ground.
The effect isn't huge - about 2 tons I think - but it's useful.

Definetely will check it out.

I have one question though, the artificial mass. What is its function? Do I need to build it or is it optional? i'm on the moon btw.

Excellent! Glad you like!
If you're interested, I also just published a battery powered Hydrogen Tanker version for refuelling the F.A.R.T.
I call it the S.H.A.R.T! You can find a workshop link in the description

@cptsavarus Thanks a lot, i'm almost finished building it. Doesn't require a lot of resources, I like it ;)

@XPERIUM... Yes, perfectly safe. The only thing that'll be missing is the A.S.S self-righting arms, which are just half-armour slopes & can easily be added manually.

It says muliple grids are not supported, only largest grid will be projected. Is it safe to build this in survival with a projector?

@CapnKitten I built mine from a projection from the build just before the A.S.S. was added :)

I'm doing all my testing in vanilla & can confirm what you found, so no, I don't think it can be blamed on mods either.
Very much appreciate the intel!
I do like to know how my workshop builds perform & if there's a problem that's for me to fix. In this case the problem is Keens but at least when people ask in the comments why it's doing this or that, I'll know what to tell them.

Agreed and will do! Think I will need to do some more testing in a pure vanilla world. I have a few mods but don't think it is that. Glad I could help you gather some info.

Cont'd.... Don't think I need any more info for now, though if you feel like sending any I'll be sure to make note of it.
I think at this point we can safely say that the engines are not working as they're supposed to and that they can't seem to make their minds up how they want to behave.
All I would ask is that you report any weirdness to Keen on the feedback site so we can get the engines fixed & working properly. Right now I feel like I want to use them but that they just can't be trusted!

@morgan... Ok, so reading that it's clear to me that there's definitely bugs.
I did a controlled test of my own yesterday & posted the results in the description... they're wildly different to yours and even more different to the results I got in a previous test.
For refuelling I resigned myself that a single O2 / H2 Gen just can't produce fast enough to keep up with the engine. Instead I just built a large grid Hydrogen tank on my base & am refuelling the truck from that. The engine still needs to be running in order for the tank to fill though, which to my mind is silly.
Didn't notice any connection between solar panel & engine but that's interesting to note - I'll definitely keep an eye out for that & see if I can narrow the problem down.....

@CapnKitten... They shouldn't be. Unless the mechanic has been changed AGAIN, projectors can still project *one* subgrid away - they just can't do daisy-chained grids.
If it doesn't project though, then yes, just build it by hand. This thing is far too small to come up with some clever trick for it - and they're so easy to build manually it's just not worth the hassle of developing a whole method.
With the one I'm testing myself, I built it from a projection before I added the A.S.S. I then added the A.S.S manually. Will try building the whole thing from a projection though & see if it works... it should.

@morgan... Excellent info! Thanks very much for that. Appreciated!
Let me sit & digest it all for a moment and I'll get back to you proper

cptsavarus: Just did a test like you asked. Saw some real funny things will take a bit of text here to share what I found.
1.) duration of H2 tank on engine --> approx 3 mins
2.) couldnt get the engine to refill without turning off the Solar Panel and toggling the O2/Gen.
3.) powering on/off of anything else will interrupt the refueling process. Not sure why the engine has to be running to refill the internal tank but that's SE. There is definitely a relationship between the Solar panel and the engine being able to refill. I had a large grid engine in beta testing and I didn't see this. Definitely weird. If there is something else you want me to test out just holler. The planet where the test was conducted was Titan.
If you want the "unabridged version" I can send you a friend request and I can spell it all out. But I was not aware of this and quite happy in my ignorance... LOL... Thanks for pointing it out. I will let you know if anything else interesting presents itself.

How do you build it in survival? The side "A.S.S."s will be a problem during construction. Do you just add them yourself? Or is there some sneaky trick?

At least I'm not the only one who found the lack of F.A.R.T longevity problematic. I do like good, strong F.A.R.T.S, but they need staying power :)

<<GASP!>>
The T.A.R.T! I almost forgot about her!
She'll be running off to join the circus if I don't give her some attention!
I'll go pounce on her now... that'll make her happy for a bit!

It would be terrible if we had a jealous T.A.R.T. ...

Does the T.A.R.T. have an A.S.S. now too?

Hehe! The worst would be if someone else crashed into your A.S.S & destroyed it!
Landing on one of the ends is pretty rare. Usually I find the engineer can just walk at it & push it over if that happens.
Landing on the roof though - well that's when it's time to get inventive with what's to hand.
I would've liked to be able to cover all eventualities but the only way I could make a flipper for landing perfectly upside down was to put the solar panel on a rotor, which looks ugly & makes it really fragile.
Grind a piston off from somewhere & weld it back on somewhere else and you can recover from pretty much any position.
Now where to mount the spare wheel without covering up the solar panel?!

That takes care of the sides, but what if you get thrown up and crash into your rear or have your front smeared in the dirt?

UPDATE V1.1
G.A.S.F.A.R.T's now come with their own A.S.S
(Awesome Self-righting System) - see new screenshots & description.
Full details in change notes.

Thanks very much @Einon. I take it because you said "Perfect" that your score is 7 out of 5 & not 5 out of 7 - 'cos 5 out of 7 would be more like "Good but could be better" Hehe!
There's always room for improvement though. I'm thinking it'd be handy if it carried a spare wheel & some other bits. Might update with those later.

@Leo... My main beef is that you can't refill it without running it. And to think - all those signs you see at petrol stations telling you to turn off your engine... they had it wrong this whole time! Who knew right?!

Yeah, the new Hydro engines generate a ridiculous amount of energy run out just as ridiculously.

So far, this is the best little truck I have seen for this game yet. I'd have to give it a perfect 5/7.

@SteelAngel... Yeah, there are some odd things going on with Hydrogen Engines right now. They're not working like intended.

I'm also testing this truck in a survival world & can confirm what you say about the O2/H2 generator not passing fuel to the engine. It seems to pass 2 Litres, then no more and only if the engine is running. Bit silly that you can only fill the engines onboard tank when the engine is busy emptying it!

I'm also noticing some really strange discrepancies with fuel consumption & the amount of fuel reported as available in the CP. In my survival world right now, this truck is currently using about 1Litre per second, which equates to about 4.5 hours of idle time. The first time I drove it after building it though, it swallowed the entire tank in less than a minute.
Definitely something isn't right.

I built this up on my survival world, and the O2/H2 generator does not seem to pass any fuel to the hydrogen engine at all. The engine burns through fuel like crazy too, giving it approximately 10 minutes of idle before the tank runs out completely. The three batteries give about 4 hours of idle.

Total range is at most a couple of km. H engines seem completely not worth it.

Hehe! Not entirely green though... the doctor says Penicillin ought to keep it localised!

SAVTec is going green!

Thanks @morgan! I had this F.A.R.T brewing for quite some time. I hope it's as satisfying as it sounds!

There's that sense of humor again. Awesome to see you building stuff and making the write ups entertaining :D I liked the little T.A.R.T. so I am sure I will like the F.A.R.T. :P

Thanks Jack! Built this one during the beta test & haven't had chance to put it through its paces properly since the actual update, so let me know if anything needs changing.

Interesting