The Caterpillar D11 is a large bulldozer produced by Caterpillar Inc. which finds application mostly in mining industry. Early D11N replaced D10 in 1986. The present D11T was introduced in 2008.
My first construction in 2018. The main goal was to build fully remotelly controlled vehicle with pneumatically functions. Any modern bulldozer is an excelent room to maneuver in this discipline. Firstly I had to optimize the scale for the size of the tracks. The only thing I have then was stock tread links and few blueprints of the original machine. The first problem I had to overcome relied on the size of the sprocket wheels. The wheel has to small diameter compare to the tread width. I simply solve that by putting 1x4 technic brick on each tread. Then I started to build the main frame that would fit all the guts inside. Contrary to what you might think, there isn't much space inside. Its probably my most packed model so far. I have in mind that there will be at least five motors, two remote controlled pneumatic switches, pendular suspension, autovalve and rest of the electronics inside. For obivous reasons I choose L motors for propulsion. One per side. Each geared down 5,001:1. To finish basis stage I had to make a pendular equalizer bar and install a compressor. The simple one. Just one small pump powered by single M motor. Inside the crawlers are located rollers and idlers for proper tension and shape of the track on every surface. Now when the tracks links were imposed the machine starting to take shape with its unique Caterpillar elevated sprocked wheel.
Time for the heart of the pneumatic system has come. The automatic shut off and two remotelly controlled valves. When the pressure is to high the cylinders overcome the strength of the rubber bands so mechanically coupled PF switch turn off the compressor. Each pneumatic switch is operated by M motor via 8z gear and clutch to prevent from damage the motor. At this point the automatic shut off is ready to test. It takes a while to calibrate it. Double small cylinder with rubber bands do the trick well. Also I found the place for the 8878 rechargeable battery box underneath the upper carriage.
Now the blade and ripper was just a formality. Each operated by double pneumatic cylinder. Of course both of them doesn't perform full functionality like tilting in this scale and type of construction. Instead of the secon pair of cylinders there are fake ones. Technically the blade is a skeleton which consist of axles, connectors and technic bricks covered by regular plates. The last but not easiest job was to install the IR receivers. Finally they landed in the operators cab.
From the visual side this is classic style construction made out of classic bricks with some details here and there such as fire extinguisher, exhaust pipes, working lights etc. The last thing I've added are custom CAT decals.