Instructions for my Excavator

[Alasdair Ryan]

Alasdair,

On the model, cylinders are placed inside, rather than on sides, mainly because LEGO cylinders are too wide in scale, compared to real ones. Also, the boom itself is a little bit wider than it should be. Boom+cylinders on side combo would be too wide.

Could you not of off set them by 1/2 a stud on the top and bottom?

[Jennifer Clark]

Well spotted Alasdair, and Milan is correct for the reason why.

I actually mention and explain this design decision in the instructions, fortunately it doesn't affect the range of motion too much.

Even if I could have reduced the boom from four studs wide to three, which would have weakened it considerably, it still wouldn't make enough room to have the cylinders on the side and keep the model to scale. The Lego cylinders are just too wide; if they were scaled to the real JS220, they'd be about 1 stud wide. Offsetting the cylinders by a half stud wouldn't work either, as the top of the yellow part of the cylinder would foul on the boom.

Jennifer

Edited January 11, 2013 by Jennifer Clark

[Alasdair Ryan]

If you offset it back to a full connection could that work?

[Blakbird]

If you offset it back to a full connection could that work?

Feel free to try to modify it to incorporate your idea! Any model of this scale involves a lot of compromises to get the range of motion right since there is only a single choice of LEGO pneumatic actuator whereas a real excavator designer can buy exactly the size they need.

[Alasdair Ryan]

Feel free to try to modify it to incorporate your idea! Any model of this scale involves a lot of compromises to get the range of motion right since there is only a single choice of LEGO pneumatic actuator whereas a real excavator designer can buy exactly the size they need.

Yes I am aware of that,but this makes building more fun.

It would be nice to see some new pneumatic rams in the future.

[sapo117]

Do you guys think it's possible to make it fully RC with LA? Don't hate me but I don't like pneumatics too much...

[Alasdair Ryan]

Do you guys think it's possible to make it fully RC with LA? Don't hate me but I don't like pneumatics too much...

There is not enough room for the motors to make this rc,and anyway it would spoil this model I think.

Check Jurgen's site out, I have made his excavator which uses la's and I can tell you that it is very good.He also make a rc backhoe loader.

[sapo117]

Thanks Alasdair Ryan I just bought the parts to make the Ultimate 8043, waiting my orders from BL. Jurgen stuff are super. BTW, I love the design of Jennifer one, but I don't like the black tail ahahah that's why I would like something RC....maybe one day when I become a PRO like you guys I will make mine as well. But first I need to accumulate tons of farts and the best practice I feel is buying instructions of PROs and assemble MOC...

[AVCampos]

first I need to accumulate tons of farts

That's easy, everybody does that, wether they want it or not.

[sapo117]

LOL....I meant parts ahahah

[Blakbird]

Do you guys think it's possible to make it fully RC with LA? Don't hate me but I don't like pneumatics too much...

Of course you can make a LA version of an excavator and plenty of people have. However, there would no point in converting this model because then it wouldn't be anything like this model any more. If you want an R/C linear actuator model then I suggest Jurgen's. One of the prime design points of this model is the fact that it uses all pneumatics for the hydraulic functions of the real excavator.

But first I need to accumulate tons of farts and the best practice I feel is buying instructions of PROs and assemble MOC...

That is a good point. If you want to learn about how to pack complex mechanics into a small space and how to use pneumatics most effectively, then I think you will get a lot from this model.

[DarkShadow73]

Of course you can make a LA version of an excavator and plenty of people have. However, there would no point in converting this model because then it wouldn't be anything like this model any more. If you want an R/C linear actuator model then I suggest Jurgen's. One of the prime design points of this model is the fact that it uses all pneumatics for the hydraulic functions of the real excavator.

That is a good point. If you want to learn about how to pack complex mechanics into a small space and how to use pneumatics most effectively, then I think you will get a lot from this model.

@Blakbird - the pneumatic tubing does make it look more realistic to the true to life excavator, much like the 8455 and 8439/64/59 does, but the drawback is the pumping and pumping of the air pump...on the cranes, such as the 8421 or the 8285 wheel lift, it isn't as much of an issue since they have very few pneumatic functions.

Edited January 13, 2013 by TechnicFreak

[Blakbird]

@Blakbird - the pneumatic tubing does make it look more realistic to the true to life excavator, much like the 8455 and 8439/64/59 does, but the drawback is the pumping and pumping of the air pump...on the cranes, such as the 8421 or the 8285 wheel lift, it isn't as much of an issue since they have very few pneumatic functions.

You don't have to pump any air pump with this model. It has an automatic compressor that produces air pressure when needed and shuts down when not needed. It runs off the same batteries as the rest of the model. And of course real excavators do the same thing. The engine doesn't actually power the excavator directly, it runs a pair of hydraulic pumps that produce pressure on demand including to rotary motors propelling the base.

[Alasdair Ryan]

You don't have to pump any air pump with this model. It has an automatic compressor that produces air pressure when needed and shuts down when not needed. It runs off the same batteries as the rest of the model. And of course real excavators do the same thing. The engine doesn't actually power the excavator directly, it runs a pair of hydraulic pumps that produce pressure on demand including to rotary motors propelling the base.

It is just about the same on my loader....

I managed to make valves that run on m-motors and fit them in,although this does take up a lot of room.

I actually fitted a pressure valve also but the air is not high enough.

Edited January 13, 2013 by Alasdair Ryan

[me00rjb]

The complexity of this model has to be seen (built) to be believed. I haven’t got all the parts yet, but couldn’t wait for the last couple of orders so made a start on building. The chassis was straight forward enough, and I'm now about half way through the superstructure.

It's definitely keeping the brain ticking over, and I've already had two good long building sessions on this one. There's hardly one standard connection in the superstructure mechanism, and it's amazing how much Lego is packed into such a small space. It's a very challenging build, and a welcome step-up from standard Lego instructions.

The number of pneumatic connections has already given me sore fingers, however I found a great tool for cutting small diameter tube (it works on the 7mm ribbed hose, 3mm rigid hose and 4mm pneumatic hose). It's definitely made building this much easier already so I’d recommend getting one. It gives a really nice clean square cut which is difficult to achieve with a knife or scissors.

http://uk.rs-online....=PSF_428494|alt

Instructions so far are great. There are a few steps where it's not 100% clear where parts are meant to go, but I actually like having to have to think about what I'm doing from time to time! I'll hopefully make a bit more progress this week, and try and post some pictures of progress.

[cheeze]

Hi folk, im new to the forum but ive come across this model before on Jennifers site. Now ive just got back into the Technic now my last model was the 8880 supercar so a lot of mine is the old studded type blocks,

Now ive just built myself a crawler crane but having a problem with a strong enough base, my question now is, would the lower base be strong enough for what i need?

[Alasdair Ryan]

Does your crawler crane use the old style grey studded turntable or uses the new stud-less version?

[cheeze]

Its the old style Alasdair, does this model use the new one? ill upload a pic soon so you can see,

[legomuppet9]

cheeze, why don't you upload your pictures to your own topic, So you don't hijack this one

[cheeze]

Ive just done that

[Jennifer Clark]

Thanks for the update me00rjb, it's a real buzz to hear that you are enjoying the build so far.

Your use of the word "dense" is a good way to describe the workings I think. Sometimes I look at these models and think "how did I do this?", but at least we have the instructions for the record :-)

Can't wait to see the photos of your work in progress!

Jennifer

The complexity of this model has to be seen (built) to be believed. I haven’t got all the parts yet, but couldn’t wait for the last couple of orders so made a start on building. The chassis was straight forward enough, and I'm now about half way through the superstructure.

It's definitely keeping the brain ticking over, and I've already had two good long building sessions on this one. There's hardly one standard connection in the superstructure mechanism, and it's amazing how much Lego is packed into such a small space. It's a very challenging build, and a welcome step-up from standard Lego instructions.

The number of pneumatic connections has already given me sore fingers, however I found a great tool for cutting small diameter tube (it works on the 7mm ribbed hose, 3mm rigid hose and 4mm pneumatic hose). It's definitely made building this much easier already so I’d recommend getting one. It gives a really nice clean square cut which is difficult to achieve with a knife or scissors.

http://uk.rs-online....=PSF_428494|alt

Instructions so far are great. There are a few steps where it's not 100% clear where parts are meant to go, but I actually like having to have to think about what I'm doing from time to time! I'll hopefully make a bit more progress this week, and try and post some pictures of progress.

[EdmanZA]

Are these lengths correct? I went through the instructions, calculating lengths and I get much higher totals for the excavator for ribbed hose and flex hoses.

[Blakbird]

Are these lengths correct? I went through the instructions, calculating lengths and I get much higher totals for the excavator for ribbed hose and flex hoses.

They are rough estimates. Calculating the overall length by adding up the individual parts the way you did is better. What totals did you come up with? I thought the parts list estimates were reasonably accurate. Note that instructions use units of studs whereas this parts list uses units of centimeters.

[EdmanZA]

They are rough estimates. Calculating the overall length by adding up the individual parts the way you did is better. What totals did you come up with? I thought the parts list estimates were reasonably accurate. Note that instructions use units of studs whereas this parts list uses units of centimeters.

The pneumatic hose length seems OK, but the others are out by 50% or more.

I made up a BOM for all the hose lengths that I counted and used a conversion of 1LU = 8mm, but I may well have missed something:

https://docs.google....MUtMZk9PcjBJcHc

Edited January 19, 2013 by EdmanZA

[nychase]

Wow... bravo. That was no small amount of work. I didn't realize how much hose that model used!

Thank you for your work!