1/10 Liebherr Excavator R 984 Litronic

[Markus K.]

Hi folks,

after the invitation to this forum i wanna introduce my actual build. I started in August 2011 with the first planings and I hope to finish the model in the upcoming year.

This Liebherr Excavator is normally used in mining and road construction and has a operation weight (backhoe attachment) of 120 metric tons. While I do the R984 my Buddy works on his R9100, whitch is a little smaller (well, not really). While he´s doing the milling parts I do most of the planing, lathe work and sheet metal welding. Sometimes I´ll throw in a picture from the R9100, but till now there are just a few. OK, enough, let´s start with the hardware!

Those parts are laser cut steel and 2mm to 5mm thick.

[Markus K.]

And some more

[Markus K.]

Hi Kevin,

thanks for your comment!

About TIG welding, this is certainly not my job or occupation and not every bead is nice, so I had to learn and practice. For me it was very helpful watch Jodie from weldingtipsandtricks. Most of his videos is about TIG welding, but he shows MIG and Stick, also. The 1st I learned was to change the Tungsten into a new grinded, sharp one once if it got stuck.
Most parts here I welded without filler rod, just heated up and melted the corners together.

Here some more pictures from the under carriage.

[Markus K.]

...and some more. If there are any question feel free to ask!

[dirtpusher9]

Welcome Markus. That's a great start to what will be a big beast when finished.

[Markus K.]

Well, it is the best if you practice again and again. Today I welded a couple hours using grey tungsten and after a while I tested the gold ones. But those didn't work as well as the grey ones, I got stuck very often with the same settings on the welder. Because of this I switched back to the gray tungsten. Pictures from this welding will be posted later.
First some pictures from the 2-stage Planetary gear inside the drive wheel. Gear ratio is 20.36 : 1.

[Markus K.]

Some more from the drive train. The gearbox is shimed with thin brass sheets for proper chain setup. The motors are brushless outrunner with 120 Watt and 760kv.

[doodlebug]

Great job on the final drives! Keep the pictures coming.
Cheer's, Neil.

[Fired up]

very nice

[JAMMER]

Hi did you cut all the internal and external gears in you drive? If you did you did a very nice job. Ed

[Markus K.]

Hi Ed,

just the internal gears are laser cut. In every drive is a stack of 10 sandpaper-cleaned pieces with a complete height of 20mm. Using thicker material is less/ poor quality. The internal gears were bought online. Sorry for the blurry picture, it shows one of the int. gears. The small brass gear was just for checking.

[JAMMER]

Hello so you laser cut the internal gears, I was thinking you cut then your self and was wondering how you did it. Your way is a lot easer than broaching them and also buying the other gears saves a lot of time but you still did a nice job. Ed

[Markus K.]

Ed, stay tuned! I'll come up with the turntable next. It has an internal gear, also, but bigger teeth and wasn't lasercut

[JAMMER]

OK I sure will be looking forward to that. Ed

[Markus K.]

Hi folks,

here now the (original built) turntable. It has an internal gear with 107 teeth, modul 2. This gear are two parts, every one got a radius on the edge for the 5,5mm steel balls. The gear is bolted to the gear carrier with 48 screws.
Then there are two outer rings with a radius for the balls, also. They are filled with 135 balls and then evenly closed with 3 screws. The upper body of the excavator will be bolted with 45 screws to the turntable.
The internal gear was done by my buddy Michael on his cnc-mill with a 0.4mm endmill. The screws were made by myself, 96 pcs for this turntable and 288 for the Michaels turntable for the R9100.

As I mounted the stuff together I found out, that the turntable need much power for turning, so I had to improve. With a sharpie I colored the ball groove and used a 5.5mm Drill shaping the groove with the drill flange, about 3 or 4 times. Now it runs smooth and without any play.

[Markus K.]

here are some selfmade screw-pics:

[JAMMER]

Nice work on the screws but cutting the internal gear on a cnc mill that took some planning and skill with the CAD. Ed

[Markus K.]

Ed, the CAD-work wasn't sooo hard. I used CATIA V with a plugin for gears. So I had only had to type in some numbers and voila... a single file came out with over 30 MB

[ihbuilder]

welcome Markus great job on the model so far Your slew assembly is exactly the way I am making them on my cat385s . I have my internal drawn and programed for the cnc mill comes to about 2 hrs cutting time .Just to find time to cut them . How long did it take to cut yours out ?

[Markus K.]

I don't know exactly because my buddy is/ was doing the milling work. I think, the mill was running about 3-4 hours. We used pre-lasered parts for this. Here some more pictures from the fabrication.