Volvo Excavator 42503

[doug72]

Volvo Excavator 42053.

Currently building this from my spare parts using Lego instructions

Reached step 126 where the blue Pneumatic pump is required.

Yellow  pump version will not fit.

As they are only available from a few sources is it really required if you use an M motor to drive the small air pump as shown in later part of the build.

Best price I cab find is approx £11 cost & shipping.

Advice would be appreciated.

[Maaboo the Witch]

If you're planning on using the motorized pump, then no.

[doug72]

7 hours ago, Maaboo35 said:

If you're planning on using the motorized pump, then no.

Thanks for your answer. Yes I intend to use motor driven pump.

I have built the motor driven air pump unit but I only had one brown cam (6039505)
For the top part  I used a stack of 4 cams p/n 6575 which have the same cross hole spacings.

The large Blue pump on order which I will use for other builds.  GBC maybe  ?

Edited August 20, 2022 by doug72

[anyUser]

The blue pump has a travel of 2L (studs). The yellow (old) one (5L long) can only do 1L. You would have to use a 1/2L crankshaft as in 8868 to drive it. But it will give you only half as much air per revolution.

[doug72]

The travel of the SMALL blue pump I am using is 3L

IMG_8821

Edited August 20, 2022 by doug72

[gvo25]

I have used 2 blue pumps with 2L travel together with an L-motor, all fit very nicely

[doug72]

Progress:-

My modified Pneumatic pump tested and runs very smoothly using an M motor. Battery box has yet to be correctly positioned.

Main boom arm moves OK in both directions. Dipper arm when lowering it falls rapidly unless you just crack open the control valve.
Could do with a restriction in the air hose for lowering.

The two buckets snap open & shut very quickly.

I Intend to modify and use the Orange Peel Grab from the Material Handler

[doug72]

Orange peel grab now fitted, using same operating method of opening & closing the grab as for the Material handler.

IMG_8822 

Tested and functions well.                        Next step is to tidy up the hoses which are a bit like  Spaghetti Junction !!!!!

Edited August 24, 2022 by doug72

[Johnny1360]

I was thinking about doing the same thing with the claw, replace it with the one from the Material Handler, as I was never happy with the way it operates.

Do you think it makes a big difference, or are they pretty much the same?

[doug72]

1 hour ago, Johnny1360 said:

I was thinking about doing the same thing with the claw, replace it with the one from the Material Handler, as I was never happy with the way it operates.

Do you think it makes a big difference, or are they pretty much the same?

I found the grab from the Material handler to be too heavy and  the main boom was very slow when raising, when lowering it was too rapid.

The grab I fitted is not from the Material handler

It is from a previous build several years ago.

It uses a shortened actuator to open & close the grab.

[Johnny1360]

Ah, I see, thanks for clearing that up.

[ukbajadave]

When I modded my 42053 I used 2 of the small pumps and a M motor which worked fine.

@doug72 How purist are you? I tidied my hoses using RC car aerial tubes.

[doug72]

Grab arm boom modified and hoses re-routed.

Tested and works OK

New batteries used for driving the pneumatic pump motor. Raising the main boom is now much better even with a Lego 6 x 2 x 3 weight in the closed grab. 

IMG_8826

IMG_8830 

Edited August 26, 2022 by doug72