pueumatic 8043 excavator

[davidmull]

I'm sorry but I have to disagree. It's not just about falling booms. This is just one example. Since you're controlling 2 pneumatic valves with one hand, you need to move it very precisely, which is quite difficult with Lego-valves. You have to pay too much attention on how far you have to push the valve, while you'd want to pay more attention to the model itself. This makes operating pneumatics less fun for me. IMO Lego pneumatic valves aren't suitable for making the pneumatic cylinder move exactly as fast as you want.

What I'm saying is that the reation of LA's is much more predictable than pneumatic cylinders. This makes it much easier to make the excavator do what you want it to do. Even when the model moves slower, it still takes less time to do the task you want. I know this from personal expierience, cause I've had a pneumatic and LA-excavator side by side.

And the pneumatic hoses connecting the remote to the excavator are a bigger issue than the "line of sight" needed for an IR-receiver. With the hoses, the model is never really "free" which annoyed me when plaaying with the pneumatic excavator.

Don't get me wrong, I'm a big fan of pneumatics, but please don't discard LA's as boring, just because you don't like them.

Well said and 100% agree,@ allenp u seem to be the only person that doesnt like la,s,both are good in there own way but when it comes to real life machine motions la,s will end of.

[rien]

Sweeeeeeeeeet but lots of cash!big boy toy

[fmmjqtft]

Sorry, can't agree here. I deal with all three of these (hydraulic actuators, pneumatic actuators, electro-mechanical actuators) on a daily basis. Hydraulics and pneumatics are structurally similar, have similar design requirements and critical cases, and operate in a similar manner within a system. EMs are totally different in almost every way except that they are also used to linearly position loads. There are almost no technical similarities between hydraulics and EMs.

From a toy perspective though, I can see your point that you feel that the LAs make the excavator movement and control look more like the real thing, but the way they work is much less like the real thing

Yes, I meant their movements, not their physical structure or the mechanisms which control them. If one motor drives one pump which is connected to one hydraulic cylinder, the movement will more closely resemble the movement of a LA.

Before I was actually replying to allanp's previous comment on the realism of the LA's movements - but I forgot to quote. My claim sure sounded funny out of context.

[Alasdair Ryan]

world war 4 has broken out

just to throw some fish at the cat who would be up to make a Ultimate pneumatic excavator out of lego? maybe with SR design or with mlcad

[rien]

world war 4 has broken out

just to throw some fish at the cat who would be up to make a Ultimate pneumatic excavator out of lego? maybe with SR design or with mlcad

I think the ultimate pneumatic excavator is jenifer's model

[Blakbird]

Blackbird you are right absolute the model of jenifer is amazing but

You say:Works good for toys though!

They are toys .

This is the real point. Not everyone uses these Technic "toys" for the same reason. Some people get Technic to play with them, operate them, etc. If you are going to play with it and want it to be fun, then I agree that the linear actuators (motorized) are better in most cases. But other people (like me) don't really play with them as much as we look at the mechanical operation of them. The lure of Technic to me is the way it works, and the more realistically it works the better I like it. That's why I like pneumatics. I don't care so much how fun it is to play with.

but blackbird you'd said that you have also hydaulic tel me tel me im curius

That quote is not about LEGO, that quote is about my real job. I work with hydraulic actuators every day.

world war 4 has broken out

No war here. Just friendly discussion. I find it interesting to hear what other people like about Technic compared to what I like.

[DLuders]

By coincidence, "jwiger" just posted this

on "Comparing LEGO large pneumatic cylinder, first generation Linear Actuator, and a new mini-LA.

P.S. When turned slowly by hand, the mini-LA was pushing a little over 2.0 kg. The faster you spin it the less force it will apply."

This test MAY help answer the question, "Which is better -- Lego Pneumatics or Linear Actuators?"

Edited January 7, 2011 by DLuders

[rgbrown]

By coincidence, "jwiger" just posted this

on "Comparing LEGO large pneumatic cylinder, first generation Linear Actuator, and a new mini-LA.

his test MAY help answer the question, "Which is better -- Lego Pneumatics or Linear Actuators?"

Or not ... that comparison makes no sense. The force you get from an LA depends on the torque of the motor driving it.

[Blakbird]

Or not ... that comparison makes no sense. The force you get from an LA depends on the torque of the motor driving it.

The maximum force from a linear actuator is based on the setting of the internal clutch. The maximum force of the pneumatic actuator is based on the pressure at which the seals leak. In either case, output force is not a useful measurement of which one is "better". The optimal design choice for a given application can only be judged against the design critera and requirements for that application. Each will win in certain cases.

[rgbrown]

The maximum force from a linear actuator is based on the setting of the internal clutch. The maximum force of the pneumatic actuator is based on the pressure at which the seals leak. In either case, output force is not a useful measurement of which one is "better". The optimal design choice for a given application can only be judged against the design critera and requirements for that application. Each will win in certain cases.

Ah, silly me I watched with the sound off - didn't realise he'd hit the clutch! So that actually is a useful measurement - both can push near 30N before physically giving way. If sheer force is the requirement, pneumatics have the advantage, of course, that it's easier to install many in parallel.

Edited January 7, 2011 by rgbrown

[imajor]

1. Ultimate 8043

2. Pneumatic excvavator DEC-24

3. Standard 8043

I think this list demonstrates well the different point of interest of the different technic fans. Those who prefer playability will probably pick 1., those who prefer similarity to the real thing will probably pick 2., and those who prefer complexicity will probably pick 3.

[allanp]

If I want a toy excavator that is only nice to play with I would get this:

http://www.otherlandtoys.co.uk/track-rc-excavator-p-2156.html

This is properly radio remote controlled, has more motors, lights and everything and is much cheaper. The thing is though, I don't want any toy, I want technic. I guess it comes down to what you want from technic. To me, what makes technic the only toy that appeals to me and unique from all the others as it has no real competition, is it's core values like authenticity and so on. There is nothing authentic to me about LAs being used in heavy construction equipment. I know pneumatics are not hydraulic but they are so similar as to be about as authentic as you can get without spending thousands on a model from Wedico (or whatever they are called). After all, both of them operate via a fluid under pressure (yes, air is a fluid )

LAs would be great if ever they made a pick and place robot! Besides the other reasons I don't like them, I only find them boring because even with a motor they are too slow and without a motor they are even worse. Cranking them until you get cramp in your fingers is not fun in anyones book. To be fair tho, the game of skill plus the always cool pffft sound of operating pneumatics and those cool looking hoses everywhere making it look like a heavy duty machine instead of a little electronic device is always gonna be cooler to me than any other motorised function.

[rien]

wedico excavator

[DarkShadow73]

Kind of agree with 'rien'...all the exposed pneumatic tubing detracts from an otherwise elegant looking model, just an opinion, not trying start a fire here. I agree that even with the new LA's it still doesn't exactly run perfectly smooth, but the looks are incredible.

Lol why?It doesent improve things .

Lifting the boom takes hours.

Jurgen desingt a great model no pneumatic needs there .

I think its too slow and the nice look the model have from it self is gone.

But keep the ideas roling!

[richthelegodude]

Hi, first post here! I am a PhD student (in engineering) and a long time lego fan.

When I was younger I always felt Lego Technic sets was crudely modelling real life machinery, the test car and Daytona super car being two perfect examples of this. Lego has shifted away from this in my personal opinion and this is what is driving this argument.

For example I did see at one point people reviewing the 8275 Bulldozer better than the 8880 Supercar. In my opinion the Bulldozer is just a toy, it makes no attempt at all to model real life (A motor for every function, and an engine which only turns over when one of the tracks is powered!)

I could go to the local toy shop and buy a remote control one – I have learned NOTHING about real life machinery .

The excavator here is a similar thing. I have drove past the JCB factory/and seen a few excavators. I have yet to see one powered by LA’s in real life oddly enough. None of the real life ones have UJ’s and prop shafts going up the booms. They have hydraulics, and pneumatics are a lot closer to hydraulics than LA’s ever will be. Real life excavators have hydraulic hoses, so I don’t buy the argument of it looking ‘ugly’ either

At the end of the day pneumatics could work just as well, if not better (at least it would be a bit quicker) with a correctly designed excavator.

And as a side note, after my dark ages – I almost swore when I opened my first modern set (the bulldozer). The boxes are like cereal boxes now, large, weak (it collapsed instantly pretty much) and have just have bags with the stuff in and no trays .

Edited January 8, 2011 by richthelegodude

[Alasdair Ryan]

Welcome to the forum.

Edited May 16, 2013 by Alasdair Ryan
Removed odd link

[rien]

Hi, first post here! I am a PhD student (in engineering) and a long time lego fan.

When I was younger I always felt Lego Technic sets was crudely modelling real life machinery, the test car and Daytona super car being two perfect examples of this. Lego has shifted away from this in my personal opinion and this is what is driving this argument.

For example I did see at one point people reviewing the 8275 Bulldozer better than the 8880 Supercar. In my opinion the Bulldozer is just a toy, it makes no attempt at all to model real life (A motor for every function, and an engine which only turns over when one of the tracks is powered!)

I could go to the local toy shop and buy a remote control one – I have learned NOTHING about real life machinery .

The excavator here is a similar thing. I have drove past the JCB factory/and seen a few excavators. I have yet to see one powered by LA’s in real life oddly enough. None of the real life ones have UJ’s and prop shafts going up the booms. They have hydraulics, and pneumatics are a lot closer to hydraulics than LA’s ever will be. Real life excavators have hydraulic hoses, so I don’t buy the argument of it looking ‘ugly’ either

At the end of the day pneumatics could work just as well, if not better (at least it would be a bit quicker) with a correctly designed excavator.

And as a side note, after my dark ages – I almost swore when I opened my first modern set (the bulldozer). The boxes are like cereal boxes now, large, weak (it collapsed instantly pretty much) and have just have bags with the stuff in and no trays .

Go to you tube searg for pneumatic and la powerd excavatord then searg for a real one look at the movements do you see a crane driver make a freefall with his bucket?

I know that if you go exactley like a pneumatic so with freefall down the pins of the real crane wont last long so to see the models digging the l,a powerd one seems more realistic

The begining of this discusion wasent about how it works but what wil be better in movement .

[fmmjqtft]

I know pneumatics and hydraulics are very similar, but there is one obvious difference that affects how pneumatics need to be controlled in order to maintain a fixed position. Air can be compressed but liquids practically can't. In a simple pneumatic set up, like Sariel's pneumatic auto-valve, a hydraulic equivalent under varied load would move more like a linear actuator.

If 1 motor per function is used, and there is no attempt to monitor the position of the pneumatic cylinder to keep it moving at a constant speed (or slower if the load is too high), I slightly prefer the use of LAs because they move in a more realistic manner.

Of course, if the aim is to accurately reproduce the mechanisms in a real machine, 1 motor per function should not be used but pneumatics should.

[GuiliuG]

Sorry to get out of the discusion but blackbird you seem to well know Jennifer Clarck, can you tell me if she definitely stops playing lego?

[richthelegodude]

Cheers Alasdair

My point is I don’t really want to play with the model to use it to scoop up my lego . I enjoy building models of real life objects rather than toys. LA’s just do not cut it for me for that very reason – they do not exist on real life excavators.

I would rather have a close technical representation of a real life device which may not move 'perfectly' than a toy which does move perfectly. Allanp has already suggested a solution to the "free falling" problem.

On a side note I have no problems controlling my air tech claw rig!

Pneumatics are begging for more innovation on Lego’s part.

[Milan]

Sorry to get out of the discusion but blackbird you seem to well know Jennifer Clarck, can you tell me if she definitely stops playing lego?

I can offer my knowledge regarding this:

She definitely stops building with LEGO.

With her last model, iconic JCB Excavator built in 2003, she didn't even provide info about new projects and her LEGO building future. There are few marks in her mobile crane section that she had desire to build another new mobile crane, but nothing happened, so far.

She build quite few models, these models are quite finished and, I could say almost perfect for their size and parts availability at the time.

Her best two creations are, arguably, JCB JS220 Excavator and her DEMAG Mobile Crane, radio controlled models, using HiTechnic parts (PF wasn't introduced back than in 2002).

She didn't lose contact with LEGO, however.

She started an Bricklink store.

After LEGO, she seems to turn on her another hobby, Music.

She is a professional bass player, session musician, band leader, arranger, and musical director with over twenty years of experience.

I wish her all the luck in her future music career, I would like I could say that I wish it for her LEGO hobby as well, but I am afraid she will never make return.

I can see sometimes that she leaves kind comments on some YouTube LEGO creations, and I am always pleased to see her be near LEGO, at least sometimes.

Too bad, as she is definitely my most inspiring and dedicated and persistent LEGO builder of all the time and one person that brought me back into the LEGO.

She will always have my gratitude for that!

[Alasdair Ryan]

she's a scot {shes from scotland}

she's a scot

Edited January 8, 2011 by Alasdair Ryan

[GuiliuG]

Thx Milan for your answer and as you say it's a pity because i consider her as a very talented builder !

I have read all her articles and i have learnt a lot of things from them ! I can thank her for it.

[locoworks]

she's a scot {shes from scotland}

she's a scot

nobody's perfect.

[allanp]

Allanp has already suggested a solution to the "free falling" problem.

There are many solutions to the free falling "problem", I just stated the obvious. You could also "balance" the weight with a spring or restrict the airflow on the appropriate port. There are many easy and obvious ways to prevent it going down to fast, it really isn't a problem.

Pneumatics are begging for more innovation on Lego’s part.

Soooooooooo true! Oh and welcome to eurobricks!