MOC: my Orange Excavator

[akong]

Hi All,

I am a new comer of here, and wanted to share my new MOC with all of you here : ]

Edited July 12, 2009 by akong

[CP5670]

Uh, that's great, but where is this MOC?

[paul_delahaye]

and ........

[VBBN]

Hmm, picture isn't working...

If you could provide the link I could get it working for you.

At least I would assume you tried to post one.

[akong]

Hmm, picture isn't working...

If you could provide the link I could get it working for you.

At least I would assume you tried to post one.

Thx a lot , i just try and finally fix , ok : ]

[RepublicForces]

pik works for me, nice piece of work you have there!

[allanp]

Hi All,

I am a new comer of here, and wanted to share my new MOC with all of you here : ]

Thankyou for sharing this looks pretty cool. And complicated too. You've even got a pivot about the vertical axis in the main boom. Well done!

Edited July 12, 2009 by allanp

[akong]

Thankyou for sharing this looks pretty cool. And complicated too. You've even got a pivot about the vertical axis in the main boom. Well done!

Yes, that is one of the main feature that i want to bring out when i build this excavator : ], u can see how it move when click on the youtube link : ]

[CP5670]

This has some very nice functions. My favorite aspect is what seem to be motorized pneumatic switches, letting you control the pneumatic functions remotely. I also like how you integrated a pressure gauge into the model.

I think the overall appearance could be improved though. The color scheme looks kind of jumbled and the cab seems to be unfinished on one side. The micromotor-powered bucket is cool, but it would be nice to have that function operated by a third pneumatic piston, considering how the rest of the model works.

[Burf2000]

Good example of new and old lego, very nice! like where you used the mini red motor

[tomacwhite]

This is my first post here, I only found the site last week.

I love this custom Excavator, it looks really great and has some interesting parts. The orange bricks are especially cool, what set has them?

I am new to the Power Functions of Technic, I had a Pnuematic red crane when I was a kid, that rocked.

I haven't played with big Technic sets for many, many years (I bought the Go Kart this year and the Snow Mobile when it came out 2 years ago). The last big set I had was 8865 when it first came out. I was 10 years old and got it for Xmas, so you can tell how old I am :) I am going to take it apart this week (if I have time with work) and clean all the parts and rebuild it. My parents visited yesterday and they think the box is still in the loft which is great! I only ever built it once (it was a monster, with some of the bricks per step being HUGE) and then it sat on my shelf for years, then in the loft in a box for years, then I got it back out again about 5 years ago, and I left it at my parents house so my nephew could play with it.

I want that new Crane Truck when it comes out, but I think I might hold off and grab the 8292 Cherry Picker and Snow Groomer instead. I can have them on my desk at work too :D

Sorry for going off topic. So, where do you get those orange bricks from?

Edited July 13, 2009 by tomacwhite

[CP5670]

I haven't played with big Technic sets for many, many years (I bought the Go Kart this year and the Snow Mobile when it came out 2 years ago). The last big set I had was 8865 when it first came out. I was 10 years old and got it for Xmas, so you can tell how old I am :) I am going to take it apart this week (if I have time with work) and clean all the parts and rebuild it. My parents visited yesterday and they think the box is still in the loft which is great! I only ever built it once (it was a monster, with some of the bricks per step being HUGE) and then it sat on my shelf for years, then in the loft in a box for years, then I got it back out again about 5 years ago, and I left it at my parents house so my nephew could play with it.

Yes, 8865 is well known for having very heavy instruction steps. There is one in particular where you build the engine, involving a staggering 134 pieces.

[tomacwhite]

Yes, 8865 is well known for having very heavy instruction steps. There is one in particular where you build the engine, involving a staggering 134 pieces.

Hee hee yup, it was indeed the V4 engine that had an insane amount of pieces. I think it took a while to do that part!

I might take some piccies of the before and after the clean and put them up here if people would like to see them?

[Burf2000]

I got the test car when i was 10 ish, however the super car 8880 was pretty heavy going as i remember, and i got both models built

[tomacwhite]

How come the movement of the Excavator is so fast in the youtube video? Is that what modern pneumatic Technic is like? Is there no way to dampen it to make it smoother? Looks very aggressive.

[Blakbird]

How come the movement of the Excavator is so fast in the youtube video? Is that what modern pneumatic Technic is like? Is there no way to dampen it to make it smoother? Looks very aggressive.

It has nothing to do with modern or old. The motorized functions are jerky because of the low gear ratio. The pneumatic functions are jerky because he is using a motorized pneumatic switch and a compressor. The compressor builds up pressure until it stalls and then the motorized switch releases it all at once. There is no flow regulator. The bouncing is due to the fact that the arm is not very stiff and is cantilivered so it has a low resonant frequency. These are all things which can be "designed out" with enough effort, although the pneumatic speed is the hardest to deal with.

[Milan]

It has nothing to do with modern or old. The motorized functions are jerky because of the low gear ratio. The pneumatic functions are jerky because he is using a motorized pneumatic switch and a compressor. The compressor builds up pressure until it stalls and then the motorized switch releases it all at once. There is no flow regulator. The bouncing is due to the fact that the arm is not very stiff and is cantilivered so it has a low resonant frequency. These are all things which can be "designed out" with enough effort, although the pneumatic speed is the hardest to deal with.

And that is the point where we are back to actuators VS pneumatics...

with actuators movement of the arm would be smoother and speed of the movement would be constant, pneumatics are easier to install on the arm, etc...

RC excavators can not really be built with pneumatics and motor-controlled switch, as blakbird said.

only switches controlled by the human hand (slow and with feeling) can provide smooth pneumatic movement.

[tomacwhite]

I don't know anything about modern Technics pneumatic systems so the explanations are a little confusing to me.

So the new pneumatics (like the new Crane Truck coming out) have got a compressor driven by a motor? You used to pump them with your hand (the old system), and its now done via a motor? Will the new Crane Truck have a really aggressive operation like this MOC Excavator? The Truck is using Pneumatics by the look of things?

Thanks so much :)

[Blakbird]

I don't know anything about modern Technics pneumatic systems so the explanations are a little confusing to me.

So the new pneumatics (like the new Crane Truck coming out) have got a compressor driven by a motor? You used to pump them with your hand (the old system), and its now done via a motor? Will the new Crane Truck have a really aggressive operation like this MOC Excavator? The Truck is using Pneumatics by the look of things?

No, this isn't quite right. LEGO never made a pneumatic set that was remotely controlled and they never made a motorized switch. In fact, only one set even had a motorized compressor. The MOC in this topic uses those features, but they were never in an official set. The new set (8258) does NOT use pneumatics. It uses what we're calling "linear actuators". This isn't very descriptive since pneumatic cylinders are also linear. The new actuators are mechanical and operate by rotating the input which turns some internal threads, extending the rod. It LOOKS like pneumatics, but it is a precision actuator.

[tomacwhite]

No, this isn't quite right. LEGO never made a pneumatic set that was remotely controlled and they never made a motorized switch. In fact, only one set even had a motorized compressor. The MOC in this topic uses those features, but they were never in an official set. The new set (8258) does NOT use pneumatics. It uses what we're calling "linear actuators". This isn't very descriptive since pneumatic cylinders are also linear. The new actuators are mechanical and operate by rotating the input which turns some internal threads, extending the rod. It LOOKS like pneumatics, but it is a precision actuator.

Ah I see, thanks for clearing that up.

I had no idea the new cylinders are mechanic, I thought they would be air still. Sounds cool :)

[paul_delahaye]

I love the way the cab vibrates as the compressor is working, looks quite realistic, but I have to say although I'm impressed how the drivers controls move i too prefer the smooth operation of the bucket rather than the pneumatic bits, but good job all the same

Paul

[tomacwhite]

What modern Lego kits have Pneumatics in them?

[akong]

After i post here, i just found the video at Youtube click over 111 views within only 2 days! : ] , that makes me happy that i can share my hobby with people over the world : ] .

The orange bricks i got mainly ordered from Bricklink, some bid from EBAY : ], i think the sellers from Bricklink got the orange liftarm and Panel from Bionicle ,Racer and from Power miners. i needed to thanks to the seller who has ship me over the world, and give me coupon discount , haha!

the Pneumatic arm move very fast at the Video course by the high pressure contained in the air container, if i control the arms immediate at the beginning from power start, the air pressure is low, it will move very smooth : ].

Below attach more photo : ]

[CP5670]

What modern Lego kits have Pneumatics in them?

They haven't appeared in Technic for some time now. The only recent set was the Lego Education pneumatics set last year, but it's pretty expensive and is meant to be an addon for the NXT. The last Technic set to include them was 8285 in 2006, although it only had one piston.

[trf199]

It has nothing to do with modern or old. The motorized functions are jerky because of the low gear ratio. The pneumatic functions are jerky because he is using a motorized pneumatic switch and a compressor. The compressor builds up pressure until it stalls and then the motorized switch releases it all at once. There is no flow regulator. The bouncing is due to the fact that the arm is not very stiff and is cantilivered so it has a low resonant frequency. These are all things which can be "designed out" with enough effort, although the pneumatic speed is the hardest to deal with.

For smoother pneumatics, could you not skip the air tank and only run the compressor when a movement is needed. This would give nice slow pneumatic movements, instead of unleashing 30PSI in the blink of an eye. You could also control the speed of the compressor motor to vary movement speeds. This of course depends on outputs used, NXT / PF etc.