1/10 Liebherr Excavator R 984 Litronic

[Espeefan]

Wow, this a big project! By big, I mean massive model! Incredible metalworking. Your attention to detail is amazing. The time consuming process of machining the track components alone is crazy. Definitely a labor of love. I'll never complain about having to make duplicate parts of 4 ever again!

[Markus K.]

Hi Folks,

it´s hard for me to find some time for working in the excavator-shop, but I did some construction work for the tubings and hoses to find out, what I've to order. All of them are needed for hydraulics except the one on top of the other. This is just for show, originally it's used for the lubrication/ grease line.
Here some results... I hope I can fab those parts. Markus.

[Erik79]

Hi Markus, to comment this work a word is enough.... AMAZING!
I like in particular the project and the construction of the transmission.
My compliments!

[Markus K.]

Thanks guys!

here my solution for the hydraulics inside the upper structure. I'll use a 3 section main valve, whitch handles the boom, stick and bucket. Exactly it is a double section valve (stick and bucket) and a single section valve (hoist) in one housing, it has two oilsupports and can be operated with two pumps..
This valve is mounted to the main distribution block, whitch also carries a smaller valve on the right side for operating the quick coupler. This block lowers the amount of hoses and helps cooling the oil. And it gives a clean look.
To support all valves with oil I constructed a pressure relief valve with 3 outputs, each seperated from the other with a check valve. A 4th output is for the pressure gauge.

[filippog]

Hi Markus,

i gave a look to your project and it is very good. I am trying to build a cat 385 CL and i have one question for you. Where did you buy the hydraulic distributors: I am looking for open centers distributors, I am using a Marzocchi pump 0,32 cc/rev.
Thanks a lot.
Filippo

[Markus K.]

here some more; the pump is direct driven and if my math are correct it will deliver round about 2 Liters/min under full load whitch will be set at 35 Bar/ ~500 PSI

[Markus K.]

There's no gear reduction in the pump. The Motor has 353KV when taking 10 amps; the revs lowers for each more amp about 4KV.
The hydraulic power output (35 Bar at 2 L/min) is 117W. For the pump I calculated 50% efficiency, so it need round about 235W on the shaft.
Due to the pump size (0.6cm³/rev) there must be a torque of 0.67Nm to reach 35 Bar. Control calculation brings ~3350 revs.

Those pumps are used very often in models, it is small and an industrial one. Markus

[Markus K.]

Kevin, I'll use 4s LiFePo, that's about 13V.

The pump itself can take revs up to 8000 (shortly) and 4000revs for a 100% running time (with HLP46 fluid). Feel free to find the data sheet for the IPZ1-HR-10 (0.6cm³/Rev)

If you know the size and efficiency of your pump you can calculate the torque it needs on the shaft:

1.59 (a fixed factor) x 0.6cm³ (amount of oil at exactly one rev) x 35 Bar (difference between input and output pressure) : 50 (efficiency) = Nm (Newtonmeter)

This torque is needed for 35 Bar at any speed! To calculate the input power for the pump you have to go this way:

Revs x Torque : 9550 (a fixed factor, also) equals Power (in Kilowatt)

Now you've to find a motor whitch generates the right amount of torque running at the right speed. My choice is a Torcman 350-20 with 14pole and 28 windings. This company fabricates the motors in a standard program, but also they make them special to fit your project (amount of windings over 30).

Anyway, I didn't check this out yet but I believe Torcman's answers and datasheets. If I start testing the hydraulic I'll let you know and post the result.

[Markus K.]

Hi Kevin,

I wouldn't do this. Better you make a drain to the suction side of the pump to get rid of leak oil. Markus.

[Markus K.]

Hi Folks,

long time passed by and for some reasons i couldn't work real much on the project. Hopefully this will change in the next weeks. Anyway, a little work was done. First I made some drawings for more lasered and waterjet cut pieces for doing the pipework on the boom. Parts are made from steel, brass and polyamid/ nylon.

First some parts for keeping the bolts in place. The bolts with the rings are screwed together. The main bolt takes a endcap and those parts clamps the ring - just simple. The locking assembly is screwed with m1.6 screws to the frame. For setting the thread at the right place I used some drilling jigs.

[Markus K.]

Next was some work on the motor housing. Drawings were made for lasercutting and bending. For welding I used a big chunk of aluminum to draw out the heat. After welding I did some filing work. The whole cover is screwed together, I won't use hinges for single opening the lids. In case I take of the whole mounting.

[JAMMER]

Hello Markus K great job on the tracks I really like them so I will take 600 hundred links how soon can you have them done? All kidding aside you have done a great job on building this excavator. Ed

[Lil Giants]

Great to see you back it Markus.

Nifty work on the pin lock mechanism.

[DADSGARAGE]

Just went through this thread again and must say this is an amazing build, all the details are astounding!! WOW!! Really like the scale too...looking forward to seeing more pics!! Keep up the top notch workmanship!!!
KP

[Markus K.]

Next I had to improve the pipe holder for the bucket cylinder. I desoldered the brass holder and used a piece of steel. Screws also in M1.6, using a 1.3mm Drill (~ 50 thou) in the brass pieces.





Pipeclamps, waterjet cut, then separated and drilled with a drill jig





And the whole assembly

[Markus K.]

Hello Filippo, i bought the Valve´s in a small shop in Germany. Unfortunately he don´t support an online shop.
Did you already check the Premacon Shop?

[filippog]

Hallo Markus, yes I did check Premacon, they are sellin Jung valves if i am not wrong, but i believe they are not with open centers. the only open centers i found are from Meinhard from Germany and he does not support on line shop and as far as I know the delivery is very long. Thanks for info.
Filippo

[Lil Giants]

Originally Posted by filippog

Hallo Markus, yes I did check Premacon, they are sellin Jung valves if i am not wrong, but i believe they are not with open centers. the only open centers i found are from Meinhard from Germany and he does not support on line shop and as far as I know the delivery is very long. Thanks for info.
Filippo

The Premacon valves are the Meinhardt design made in steel by? ...is it Jung? Why the need to have them made in steel is beyond me.

All of Fumotec's valves come from Meinhardt.

[calum_scania]

Originally Posted by Lil Giants

The Premacon valves are the Meinhardt design made in steel by? ...is it Jung? Why the need to have them made in steel is beyond me.

All of Fumotec's valves come from Meinhardt.

Joe I ordered valves from Premacon and they are the exact same as fumotec supply but made of steel. My reasoning was to add a little extra weight to the machine

Calum

[Markus K.]

Hi folks,

yes, I´m using Meinhardt Valves (the big Mega Blocks - i´ve to handle about 2 liters per minute). He don´t support an online shop and he makes not as many as he could sell. Because he don´t need to, it´s not his business, it´s his hobby.
Premacon Valves are fabricated by Jung Fluid. But I can´t tell wether those are open or closed center. I simply would ask premacon via mail.