Gee's General Newbie Topic

[Gee]

Yeah, I dig that, but most PF powered models don't go that fast. What if you are building a crawler or other slow off-road vehicle?

[Alasdair Ryan]

For a crawler you will need suspension to cope with uneven ground,without it your truck will roll over.

[Gee]

Yeah, I understand that, but as I said earlier, a simple pendular system will keep all wheels in contact with the ground without the need for a complicated system with it's extra weight and complexity. The other thing is that a lot of the off-road models that I see (including 9398) don't have suspension that works very well. At rest the suspension is at full extension for starters.

I like seeing suspension working but are all these fancy springs and linkages etc actually needed in a LEGO model, or are they all for show? If the latter, I totally dig that, it's a feature of a model.

[Alasdair Ryan]

I agree it will,but for some races or trails you may find that the performance is not that great.

The more advanced set ups will preform better than a basic set-up.

Linkages just improve the strength of the fixing to the rest of the model.

[legolijntje]

Well, pendular suspension doesn't always keep all wheels in contact with the ground. It's still a rigid axle, but the only main advantage of it is that it can turn the front axle in another direction compared to the back axle. The wheels itself on both axles are still on 1 line.

That's a kinda vague explanation...

[Alasdair Ryan]

The other thing is that a lot of the off-road models that I see (including 9398) don't have suspension that works very well. At rest the suspension is at full extension for starters.

That is were you want it to be,you don't want it to be short in movement otherwise it will limit performance.

[Gee]

I understand ya Merlijn. Under what circumstances will a pendular set-up have a wheel off the ground? (Obviously this is governed by the limit of the suspensions movement in the same way that a 4-link/independent system is governed by the travel of the shocks).

I thought that you didn't want it fully extended at rest. What if you drive forward and hit a pothole? The entire vehicle will sink into it instead of the suspension expanding to take up the slack.

I can't believe that a 4 link suspension system has a stronger link to the chassis than a simple pendular system.

[Blakbird]

All off-road construction equipment has pendular type multi-axle suspension which keeps the wheels on the ground provided that is it not too uneven. Very rarely is it sprung. This works fine as long as you are going slow. However, inertial effects become very important once you are not going slow, so a sprung suspension forces a wheel down into a divot instead of skipping over the top at speed. Sprung suspension also reduces the dynamic stresses imparted to the chassis from the terrain. It's not just about passenger comfort. For example, R/C cars have no passengers but they all have sprung, damped suspension. Try driving one without it and you will find control impossible. You'll also break a lot of parts.

As for Lego, you are largely right that at typical slow Lego IR R/C speeds with typical spongy balloon tires, sprung suspension doesn't add anything practical. What it does add is realism which is important to many builders. If you want performance then Lego R/C is not the way to go anyway.

For a counterexample, check out

from Sariel. This Lego model is fast enough for the suspension to be relevant. Look at the onboard video and see how stable the camera is compared to the unsprung mass at the wheels.

[Gee]

Thanks Blakbird, that's the answer I was after (as in you answered my question, not you told me what I wanted to hear).

I've seen Sariel's Trophy Truck and it's hugely impressive, especially the suspension moving in the slo-mo. Of course, this is not the norm and it's powered by a buggy motor for a start.

I like going slower anyways. My Brother used to have a proper RC car and it was fast, but very unwieldy and not that much fun to drive. You always got the feeling that you were on the ragged edge of control because it went so fast.

I totally understand builders wanting to add complexity and realism into their models. I spent countless hours of my childhood slowly pushing 8865 around the floor and watching exactly how the suspension worked. Fascinating. Of course, 8865 was one of the only LEGO cars that was sprung correctly too.

These days I'm more interested in building simple things (probably due to lack of skills) that perform well. For me, at this stage, suspension is a lot of hard work for no reward!

[Gee]

Introducing this weekend's crap MOCs!

First a tracked thing using Sariel's subtractor. Worked nice enough, but I couldn't get the right setup with the road wheels and return rollers. The result was that it shook like hell when driving!

Then I made this simple car with pendular suspension using a mini-turntable. This works really nicely and now that I have got a diff that makes a world of difference to the turning ability (obviously). I think that a large turntable would have been easier to attach and also more sturdy. Other than that, this is fun to play with, quick enough and handles nicely.

Your thoughts, as ever, welcome!

[Azzepa]

They are most definitely not crap,

First a tracked thing using Sariel's subtractor. Worked nice enough, but I couldn't get the right setup with the road wheels and return rollers. The result was that it shook like hell when driving!

I like that, nice mix of studless and studfull construction, and with a bit of tweaking would probably work just like you wanted!

Then I made this simple car with pendular suspension using a mini-turntable. This works really nicely and now that I have got a diff that makes a world of difference to the turning ability (obviously). I think that a large turntable would have been easier to attach and also more sturdy. Other than that, this is fun to play with, quick enough and handles nicely.

Always love seeing people's compact RC mobiles, and that's a fine job with fitting the pendular suspension in there. With those large wheels and an XL motor in the mix, I can imagine that moving quite quickly too! Mighty fine job. :thumbup:

Also reminded me to do some more work myself on compact RC cars. Having two running around is much fun, racing them around with family/friends. Cheers

P.S: You have the same place-mats on your table as I do

[Junpei]

Crap? Those things are pretty damn cool. The car is awesome for your first fully studless build, and it looks like it performs very well.

Can't wait to see what your MOCs evolve into in the future.

TLH

[skppo]

So when can we drop the "newbie" from the topic name?

These look pretty cool! The tracks just might be bouncy by nature.

[Gee]

Thanks very much for the kind words guys! I guess I was a little harsh on myself.

The tracked thing was cool, but the single XL motor started to struggle a bit and the medium had a really hard time turning it around. My batteries are probably on their way out too, so this didn't help. I'd like to re-visit the tracked thing again, and concentrate on making it better.

I'd like to turn the car into a 4wd somehow, whilst still keeping the pendular suspension (will probably have to get a large turntable off BL) and retaining as much simplicity as possible. It's the first thing that I've made with studless that I'm really pleased with. It's sturdy enough and performs well. With fresh batteries I think that it'd be quite quick too. One thing that I am rubbish at is bodywork, which is why I didn't bother at all on this one!

I'm still suffering from a lack of parts (liftarms mainly) and also I'm limited by not really having much experience of building in studless so I'm learning the building techniques whilst I am going along. Perhaps I would be better off buying a large set so that I have the opportunity to learn how the pieces go together and also to boost my parts bin.

[Azzepa]

I'm still suffering from a lack of parts (liftarms mainly) and also I'm limited by not really having much experience of building in studless so I'm learning the building techniques whilst I am going along. Perhaps I would be better off buying a large set so that I have the opportunity to learn how the pieces go together and also to boost my parts bin.

42009 is a good parts pack, a plethora of beams from that, with the yellows, greys and blacks. 8258 was also a great parts pack, if you can get one cheaply (I hear the price is through the roof since it retired); again plenty of neutral colours and the red, with some yellow. Flagships generally make great parts packs from what I have bought, have all of them since the 8258 and they do a good job of bolstering the collection.

Happy Collecting!

[Gee]

If only I had the moo-lah to spend on those! I wouldn't mind 42009, but £150 is out of the question and besides, I don't really want another battery box and all those wheels that I'll probably never use. 8258 is, as you say, astronomical in price. From what I see, as soon as a set gets retired then it's price goes up massively and you can't find it anywhere!.

There's nothing in the current 1H 2014 that I like the look of and I don't think that I'll be able to afford the flagship Volvo Loader of 2h 2014, so I may end up buying something like 42006 for the parts. At least that would give me a big turntable and some LAs (I have neither at present), a load of gears and some more tracks (which I will undoubtedly use in GBC machines when I get round to it).

[Azzepa]

42006 looks like a good parts pack, looking at the recent years of sets there doesn't seem to have been many tracked vehicles since 8043 so looks like a good choice, especially with those LAs, very useful.

I agree with you in terms of 1H 2014, not a lot seems interesting to me as well, although 42024 doesn't seem too bad in terms of parts if you're looking for LAs and Gears, it has it's fair share of those it seems. I prefer 42006 though as a set.

You can however pick up LAs on BL for around £3.50 each, if you need them without buying a set

[Gee]

I was looking at getting some of the things that I wanted on BL, but when it comes down to it I'm lacking basic things like 3L pins and liftarms so at the end of the day it will probably be more economic to buy a set.

[Lakop]

Gee,

Good to see you are getting the hang of it now. Both your models are good and have potential. Keep on keeping on.

H

I was looking at getting some of the things that I wanted on BL, but when it comes down to it I'm lacking basic things like 3L pins and liftarms so at the end of the day it will probably be more economic to buy a set.

it might be worth checking brickset to see a parts list before you buy a set. The new skip/container truck might be a good one to get. It looks like lego are clearing out again for 2014.

Let us know what you get.

H

Edited January 12, 2014 by Horace T

[Jim]

Gee, your title seems to indicate you are not a newbie?!

[Gee]

Eh? I don't follow Jim. If you changed the title then I can't see it. I was thinking it could be changed to something like "Gee's AFOL Learning Curve", although I'm still pretty much a newbie!

I don't think I'm quite ready for it to be titled Gee's MOCs yet!

I've just ordered 42006 from S@H so I'm looking forward to putting that together and learning more and also having more parts to play with. Ordered a PF switch too so I can motorize it.

[Jim]

Take a look beneath your profile picture

[Gee]

Oh right! LOL! How did I miss that?!

Cheers Jim!

[Jim]

Oh right! LOL! How did I miss that?!

Cheers Jim!

(the crazy Scott Ryan Alasdair made the suggestion btw)

[Gee]

I'm flattered!