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1 hour ago, Appie said:

@tomek9210No reply regarding the suspension? For this model I am probably not changing it at this point even if there is a better configuration, since this works and fits, but knowledge on this will be good to have for new builds. So interested to hear what you think (or anybody else who feels like chiming in). 

 

This is my experience and just physics. Compressing force is verical, so when the spring is mounted this way, it helds more weight than angled one. Imagine the triangle of forces.

But this is your setup, you know all details and space you can use in front suspension, so whatever suits your needs is ok :) Have you thought about adding torsion bar and anti-roll bar?

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Posted (edited)

Ok, noted on the suspension then. I dismissed the veritcal mounts from the start pretty much on the Beach Buggy experience alone, but good to know for a next time. Vertical mounts on this car would fit I think and perhaps I would only have to use 2 hard springs then, but since the current setup works, I am not going to bother taking apart 50% of the car for that at this point.

I am not a fan of the usual Lego torsion bar method that involves twisting axles, so no and I never considered an anti-roll bar, but even if I did, there'd be no space for it.

Edited by Appie

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Posted (edited)

Meant to edit my last post instead of double post, but anyway:

One question though @tomek9210, because while I do not want to dispute physics (as if I could), after reading your comment I am trying to figure out why the suspension was stronger in my second setup at the front than the first, while I increased the angle. I could write it off as a placebo effect, but that doesn't make sense to me considering the course of events. I found one of the posts I read before this MOC from Didumos and Erik Leppen on this matter and while I didn't fully understand it at that time, I think I get what they mean now. It's about this post

On 6/5/2018 at 7:53 AM, Didumos69 said:

+1. @Erik Leppen explained this once very nicely. Draw a line through the rotation point of the suspension arm to which the shock is mounted, orthogonal to the length of the shock. The distance between the rotation point and the shock defines the 'arm' and the longer the arm, the bigger the moment of force, the stronger the suspension.

suspensions.png

 

Could it be explained that because I increased the distance between the rotation point of the suspension arm and the shock in that second setup at the front, it made the suspension stronger, despite the increased angle? This would also explain why the Beach Buggy was so soft on the suspension. Sorry to bother you with this, just trying to grasp the physics behind all this.

For reference I shamelessly abused Didumos render in that post to show the 2 setups I had for the springs (the red lines) for the front on the Phantom:

48638317328_8b2faebf70_z.jpgPhantomFrontSetup1-2 by Appie NL, on Flickr

Edited by Appie

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20 hours ago, Appie said:

Could it be explained that because I increased the distance between the rotation point of the suspension arm and the shock in that second setup at the front, it made the suspension stronger, despite the increased angle?

That makes perfect sense.

20 hours ago, Appie said:

This would also explain why the Beach Buggy was so soft on the suspension. Sorry to bother you with this, just trying to grasp the physics behind all this.

Probably, however, the distance between shock and rotation point is one thing, but the length of the suspension arm also plays a role. The distance between the shock and the rotation point defines the relation between weight and shock compression, but a longer suspension arm may feel softer simply because it has more travel. It will require less weight (= less shock compression) to make the same absolute travel.

So a light buggy may sink into its suspension under its own weight just as much as a heavy car using the same shock placement, simply by applying longer suspension arms.

Great car btw :classic:

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Thanks for the information Didumos and the compliment :classic:

 

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There were reasons why I didn´t want to comment on this (great!) model. The first prototype shown didn´t convince me at all with its non-constistent mix of panels & bricks. And maybe because I don´t like bulky heavy vehicles transporting fat dictators, with umbrellas costing a decadent amounts of 700,00$+ :laugh:.

The OP was asking for opinions, willing to improve everything meticulously over and over again. With the effort of the fruitfull discussion the results are respect demanding. Most of all I apreciate the functionality, especially the windows moving :wub: and of course the belly shot. Thanks for sharing with us your love for this car, the interesting engineering solutions and all the fun you´ve had :moar:!

Edited by brunojj1

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4 hours ago, LEGO Train 12 Volts said:

SUPERB! :wub_drool:

Beautiful and expensive car (also in Lego bricks :wink:)!

Thanks! It did cost a bit, but that's mostly because I hardly had any dark blue bricks/Technic before starting this model. Luckily I got an order in when Lego's brick order system still worked for my country, since most of the stuff on this car is currently being produced (3L dark blue liftarm, dark blue 3x3 half liftarm and some metallic silver parts being the only exception I think). One part I did avoid using during the build was the 5L dark blue liftarms (hard to come by on bricklink) and simply replaced those with 5x3 L-shape dark blue liftarms, which are readily available. In case you want to know where: there's 6 (3 on each side) L-shaped liftarms hidden on the sides of the trunk.

@brunojj1

Thank you very much! I really appreciated the feedback I got on this model in this topic on things to improve upon. So I want to say thanks to everybody for that.

Edited by Appie

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@Attika and @Gray Gear and anybody else who wanted to know.

I actually put the car on the scale and first of all my apologies, I seem to have completely misjudged the weight of this car :look:. It isn't even close to 10kg, it's about 4.8kg :oh3:

Quite a big difference from my estimate, I used to be good at guessing weight, not anymore I guess.:grin:

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Somehow have missed all the updates, mindblowing creation *huh* The "practical" functions as the power windows and AC are a very unique touch, certainly makes this stand out from the trillionth supercar w/ a gearbox! Just insane to see how much functionality has been fitted into this beautiful package :wub:

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On 9/3/2019 at 6:20 PM, Appie said:

@Attika and @Gray Gear and anybody else who wanted to know.

I actually put the car on the scale and first of all my apologies, I seem to have completely misjudged the weight of this car :look:. It isn't even close to 10kg, it's about 4.8kg :oh3:

Quite a big difference from my estimate, I used to be good at guessing weight, not anymore I guess.:grin:

That info puts the model in a different perspective. Now I belive it can be moved by the drivetrain. It is still a massive weight though. :classic:

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6 minutes ago, Attika said:

That info puts the model in a different perspective. Now I belive it can be moved by the drivetrain. It is still a massive weight though. :classic:

Nothing a couple of the new hubs wouldn't be able to handle.

Edited by Zerobricks

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On 9/4/2019 at 12:07 AM, syclone said:

Somehow have missed all the updates, mindblowing creation *huh* The "practical" functions as the power windows and AC are a very unique touch, certainly makes this stand out from the trillionth supercar w/ a gearbox! Just insane to see how much functionality has been fitted into this beautiful package :wub:

Thanks!

1 hour ago, Attika said:

That info puts the model in a different perspective. Now I belive it can be moved by the drivetrain. It is still a massive weight though. :classic:

Could you explain to me why a geared down and well braced gearbox (not trying to be arrogant, but it isn't my design, so I can say that :classic:) would have trouble moving a 10kg car? It's a manual driven model, so the only issue would come from what it is given from the wheels. I can understand if the car would be bending or RC driven that it would strain the drivetrain, but that isn't the case and I think I also mentioned I pushed it around the living room to see the gearshifts work. So I am not sure where your initial doubt comes from, but perhaps you simply missed those messages or there's something else I am not thinking of?

Edited by Appie
typo

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27 minutes ago, Appie said:

 

It's a manual driven model, so the only issue would come from what it is given from the wheels.

oooops. That explains a lot. :sweet: My bad. I don't know why, but I had the misconception that it's motorized "there" as well.

In this case I apologise for the related part my first comment and DO NOT use the planetary hubs :ugh:. Would be the craziest idea ever. :grin: 

Your arrogance was mild and too late, you should have questioned me about my (turns out to be ridiculous) recommendation straight away. :sadnew:  Boy, I feel stupid. :classic:

 

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@Attika Ah ok, now it makes sense to me. I just now noticed you mentioned the new hubs earlier (last week), I missed that sorry. I suppose that's the "recommendation" you meant. Yeah, no desire to mount those :laugh:

 

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