View Single Post
  #27  
Old 04-10-2016, 08:01 PM
dozerbuilder dozerbuilder is offline
Newbie
 
Join Date: Dec 2014
Posts: 93
dozerbuilder is on a distinguished road
Default Re: Russian ChTz T-800 1/16th scale Bulldozer model

The big T-800 dozer finally succumbs to field testing ripping loose rock. Appears a stone became entangled in between the bottom rock-guard rails and the RH rear sprocket while screwing the tractor. With the front idler tensioner pulled right back and the rock in between the bush and the sprocket gullet, something more had to give to accommodate the stone and it was the track links. We pressed the pins and bushes out and replaced two complete grouser and link sets. Took about 1 hour and back into service. I guess it’s far easier to replace two track link/grouser sets than twist up the final drive which can be got at through belly pan covers but is quiet time-consuming and requires roll-pins to be driven out.

The final drive seems to be immensely strong even though I’ve wound the mixing back on the Turnigy to 40%. I’m very happy with it. For those who are interested, the drive comprises 2x 25Amp (stall) car seat motors (made by Hyundai) running @3000rpm motor output speed (no load) with 16:1 worm drive reduction at the right-angle output shafts then another 4:1 reduction in the final drive which is done with 04B simplex chain and sprockets roll-pinned to 8mm dia output shafts. The drive can run at 47.5rpm full speed down to 0rpm at full motor torque using PWM. So my sprocket speed at 40% is running 19rpm which as can be seen in the other vids is about right. I also plumbed up the umbilical cord to my PC linking the 2x35amp DE dual motor ESC’s on the dozer and DE’s Describe software and used ramping to take the jerkiness out of the drive system, that’s why it runs so smooth between forward and reverse and turns.

Here’s the vid that shows the carnage.


https://www.youtube.com/watch?v=2rw9BWBx-34
Reply With Quote