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It works very well, but generally requires an M motor and compressor for every valve. Not very cost efficient.

Yeah, I was afraid that was the only feasible solution. Indeed not very cost efficient, and not very compact either.

Have a look at my loader too. :wink:

Looks pretty cool Alasdair, did you put it on Rebrickable?

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i thought sariel's wheel loader used only one compressor motor, how did he do it? i might go check again actually.

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Remember that to properly move a valve using a servo that you should gear it down by about 2:1, 20:12 is close enough, because the valve does not move as far as the servo. This will in effect increase the servo resolution. Alasdair's solution of mechanically limiting the valves movement is probably the best solution if you have room for it. You can limit the valves movement very precisely by using a lever that is adjusted by a 24t gear mated to a worm gear to give you infinite adjustment. Then use a spring as the link between the servo and the valve so that the servo can move to it's full range without being over strained. This works great because you can activate the servo so it opens the valve, allowing the load on the cylinder to drop. Then slowly adjust the worm gear until you here the faint hiss of air that Blakbird was talking about and boom, your heavy load will lower nicely and controlled every time, even with a bang bang remote.

Love that description! would very much like to see it irl :)

can't wait to get home & try..

remote controlled the crane on my 8110 while back, the valve-controllers took the entire bed-place, but steering the crane was virtually impossible due to waaay to quick actions of the boom, especially the upper boom arm

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You know, I'm still waiting on the first proper MOC that manages to succesfully incorporate remote-controlled pneumatics :laugh:

No, it's really easy and effective, when using remote controlled pneu. in a simple on/off system like a tipping bed..

waay more difficult when using it on a system like svinging the back hoe from side to side on the 8455 or a crane or similar, where it's needed to stop the piston mid-way..

But I don't understand why some claim it is needed to have a compressor for each valve when the system is remote controlled....?

I tried connecting a servo motor to a pneumatic switch (see below). As allanp mentioned, I have the servo geared down using 12 and 24 tooth gears. I made that video about 2 years ago so I'm trying to remember how easy it was to operate. As Blakbird mentioned, it was still difficult to get that sweet spot where the air is just seeping - one step of the servo motor too far, and the switch opens up too much and air rushes into the cylinder.

Having a system of course adjustment (with the servo) and fine adjustment (with a worm gear), linked together with a differential is an interesting idea, although I'm not sure how practical it would be to operate, and it would use 2 motors and two remote channels.

Watch on YouTube for additional annotations:

Stroke of genious there!

That's excactly what I thought of, very very nice, even fits snugly in a vehicle.. And one large, well build compressor can supply several valves

thank you so much for that reply!

- and VERY nice loader @ Alasdair Ryan !

Edited by H3NRIK

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How about just M motor with worm gear to a 24 tooth gear on the switch? Or maybe additional reduction?

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How about just M motor with worm gear to a 24 tooth gear on the switch? Or maybe additional reduction?

That's also a solution described a little longer up the thread... :)

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No, it's really easy and effective, when using remote controlled pneu. in a simple on/off system like a tipping bed..

waay more difficult when using it on a system like svinging the back hoe from side to side on the 8455 or a crane or similar, where it's needed to stop the piston mid-way..

Yeah, I should've mentioned I'd like to see fine-grained control.

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i build them play whit it MOD them and then take them apart to use them in MOC's and MOD's

I build them and play them but I don't disassemble them.

Edited by MrPaulo23

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Looks pretty cool Alasdair, did you put it on Rebrickable?

The valve?

I have a LA loader that will be going up soon....

- and VERY nice loader @ Alasdair Ryan !

Thanks.

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I never disassemble any of my official LEGO sets - I love them too much, especially the big and expensive stuff like the LEGO Technic flagships.

Same here I never disassemble them, the bigger sets I have 9397, 8110 x2, 41999, 42000, 42029, 42022, 42037 to mention my lean composed Technic fleet are all modded and reinforced to last.

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Same here I never disassemble them, the bigger sets I have 9397, 8110 x2, 41999, 42000, 42029, 42022, 42037 to mention my lean composed Technic fleet are all modded and reinforced to last.

Had to sacrifice my ultimate 8043 for parts.... (and 8275 offcourse) ;(

But other than that, they all sit neatly on the shelf, modded like hell :)

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I tried connecting a servo motor to a pneumatic switch (see below). As allanp mentioned, I have the servo geared down using 12 and 24 tooth gears. I made that video about 2 years ago so I'm trying to remember how easy it was to operate. As Blakbird mentioned, it was still difficult to get that sweet spot where the air is just seeping - one step of the servo motor too far, and the switch opens up too much and air rushes into the cylinder.

Having a system of course adjustment (with the servo) and fine adjustment (with a worm gear), linked together with a differential is an interesting idea, although I'm not sure how practical it would be to operate, and it would use 2 motors and two remote channels.

Watch on YouTube for additional annotations

From the video it looks like position 3/7 of the Servo motor is enough to turn the valve on at almost full air flow.

I suggest you increase the gear ratio so that position 7/7 is where position 3/7 is at the moment, then control the Servo to position 6/7 to find a partial flow position.

You have a gear ratio of 12:24 at the moment so 12:56 (turntable) would be OK, or 8:36.

It might be easier to have a 1M lever on the servo e.g. 2x 2M "++" half beam, and a longer lever on the switch valve arm, extended with an axle extender.

I used this method to hover around the partial flow sweet spot for my variable pneumatic servo.

I used two valves in parallel so each cylinder nozzle can have a valve sitting on the sweet spot.

Mark

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From the video it looks like position 3/7 of the Servo motor is enough to turn the valve on at almost full air flow.

I suggest you increase the gear ratio so that position 7/7 is where position 3/7 is at the moment, then control the Servo to position 6/7 to find a partial flow position.

You have a gear ratio of 12:24 at the moment so 12:56 (turntable) would be OK, or 8:36.

It might be easier to have a 1M lever on the servo e.g. 2x 2M "++" half beam, and a longer lever on the switch valve arm, extended with an axle extender.

I used this method to hover around the partial flow sweet spot for my variable pneumatic servo.

I used two valves in parallel so each cylinder nozzle can have a valve sitting on the sweet spot.

Mark

WOW that looks interesting, Mark !!

I have got to try that at home....

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Voila, from 2011:

I remember when you made that valve! I was very impressed at the time and still am. However, obviously a LEGO offering would be self contained and much smaller.

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Ok back to the 2h models ha the toy fair is over so I take it that's pretty much all were going to get video wise. A bit more info would be nice on the crane but i think we have to just wait now till July :(

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Ok back to the 2h models ha the toy fair is over so I take it that's pretty much all were going to get video wise. A bit more info would be nice on the crane but i think we have to just wait now till July :(

Well promobricks promised to upload another, more detailed video showing the Merc Arocs and Crawler Crane either later this evening or tomorrow. We should definitely get another video :)

Edited by Emmi

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Well promobricks promised to upload another, more detailed video showing the Merc Arocs and Crawler Crane either later this evening or tomorrow. We should definitely get another video :)

That sounds good :)

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That sounds good :)

Definitely, if there weren't Promobricks taking pictures at the Fair we still wouldn't have proper pictures of the Fireplane. Definitely best coverage of the Technic sets this year.

Edited by Emmi

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Hello friends, it has been a loooooong time since I have been on.

All I can say is I am amazed by this model. It integrates Lego 8258 Crane Truck and Lego 8110 Unimog very well. I am used to seeing Lego Technic mostly make 2 discrete models: a model that favours realism in the drivetrain, so like complex suspension and stuff and gearboxes with large fake engines or motors (for example 8297, 9398, 8466), or smaller scale models that favours good looks and immense functionality like cranes or liftarms or other industrial features/machines (for example 8258, 8285 [to an extent], 8043, 8421, 42009). Lego 8110 is kinda mixed for me. It is a large scale model that favours functionality of drivetrain over its "industrial" functions, which is why the complex suspension ended up with the Unimog having poor steering,having very primitive stabilizers and a simple pneumatic crane (not to mention the gearbox involving alot of universal joints as shortcuts instead of using gears). But this new Mercedes-Benz Arocs is a perfect mixture of the two types of Technic models to be available. It is a small scaled model (like 8258 sized) that has nice function, like the motorized stabilizers, the crane with the extending arm, the tipping bed, and the closing bucket on the end of the liftarm. But it also has a complex drivetrain, meaning full independent suspension (I think. I do see 8 springs on the truck, 2 for each axle), and a drivetrain that leads to a fake engine. It also looks aesthetically nice for a small scaled model, and a very complex gearbox (for the function, not drivetrain). I see some new parts have been released in the time I have been away, like these new pneumatic cylinders, and this new turntable. Also other small parts that I have never seen before. The use of the l-motor also seems to be taking over the job of the m-motor in most cases. But i have some concerns for this new model too.

1) Am I the only one who notices that the whole structural integrity of this truck is a bit jiggly? Like the way the whole cabin shakes when the guy simply moves some switches on the gearbox?

2) Why would the Lego Technic team use 4 hard, yellow springs for the the front 4 wheels, and use 4 grey, soft springs for the rear doubled wheels? It seems that there is more weight in the back, and soft springs would make the rear too sensitive to any applied weight.

3) Do the wheels seem just a bit too undersized? I think the ever-so-slightly bigger wheels of Lego 5571 would be a better fit? What do you think?

4) What is everyone talking about this new valve that they want? Did Lego promise a new valve? Is this going to be a PF valve?

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Love that description! would very much like to see it irl :)

can't wait to get home & try..

remote controlled the crane on my 8110 while back, the valve-controllers took the entire bed-place, but steering the crane was virtually impossible due to waaay to quick actions of the boom, especially the upper boom arm

Here's a quick mock up.

adjustablevalve.png

The servo moves through it's full range using the bang bang remote. By turning the 12t double bevel gear on the far right side you can adjust the speed at which a heavy load like a crane boom comes down. It's very precise, you can adjust it so that you have to pump it a little to get it to come down. This quick mock up has a flaw though. To properly place the servo it really needs to be 1 stud higher and half a stud back. It works great but the position of the servo makes the spring want to push the yellow connector of the top of the valve, but it gives you the idea of what I mean. Hope you find it useful :classic:

Edited by allanp

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Hello..

Been following this thread from the start, no indication of PF valve...

Legoworld Copenhagen is coming up next weekend, Think I will take my son

Edited by H3NRIK

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A bit Off-Topic but: Anyone knows of a Toy Fair in the US where Lego is typically displayed? Granted, the variety/selection of toys in Germany/EU is unique, and such market justifies dedicated Fairs.

We have the Chicago Auto Show here next week, but I'm after 'smaller' toys.

Edited by DrJB

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Definitely, if there weren't Promobricks taking pictures at the Fair we still wouldn't have proper pictures of the Fireplane. Definitely best coverage of the Technic sets this year.

Will u upload the video on here?

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Here's a quick mock up.

adjustablevalve.png

:classic:

Yes thanks Allan!

Makes lots of sense, now I see why this setup will use 2 PF channels, but it'll be worth it, controlling an upper crane arm!

Thank you so much for taking your time to share!

Really appreciate it.

PS my Phone didn't Update until now, just realized you had posted @ me

Edited by H3NRIK

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Yes thanks Allan!

Makes lots of sense, now I see why this setup will use 2 PF channels, but it'll be worth it, controlling an upper crane arm!

Thank you so much for taking your time to share!

Really appreciate it.

PS my Phone didn't Update until now, just realized you had posted @ me

Should only need one PF channel for the servo. The adjustment is done manually and only needs to be set once unless you want to adjust it remotely.

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