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TheBennyB
05-03-2017, 10:30 PM
Bare in mind I in no way am around heavy equipment other than r/c. I've notice that western operators lead with the sprocket while EU operators lead with the idler. Mainly with excavators. Is there something to this or am I just over analyzing youtube vids?

sparkycuda
05-03-2017, 11:59 PM
The "front" vs "rear" of the undercarriage is determined by the operator controls. All manufacturers I'm familiar with designate the idler end as "front" and the track controls work correctly in that direction. If the upper works are rotated 180 degress (operator being over the sprockets) the track controls are backwards. Additionally, there are other reasons the idler is the "front". The track recoil spring is mounted behind the idler to absorb shock loads as the machine moves and hits rocks, etc. Sprockets pull the tracks directly when going forward, as opposed to reverse, when the track is under tension on top, around the idler, and on the bottom - increasing track wear significantly. Excavators typically don't travel very fast or far, so going either direction is not as detrimental as on a dozer. Besides, if you are straddling a ditch, you don't have much choice about which end leads! Hope that helps.

Ken

TheBennyB
05-04-2017, 12:24 AM
Thanks Ken. Yea, think I just saw a couple on instances that got my head going.

Colin11123
05-04-2017, 04:26 PM
General rule of thumb is, on the flat or uphill sprockets to the rear to keep the lower part of the track taught, sprockets at the front going down hill for the same reason.

FabOne
05-04-2017, 07:51 PM
Ken-

THANKS for educating me! Your explanation was GREAT.

-Terry

tc1cat
05-05-2017, 03:48 PM
With this all being said, why do some tanks have a front drive sprocket and some have a rear drive sprocket? Most tanks prior to 1940 had a front drive sprocket. The Russians were the first to use rear drive sprockets to my knowledge-T-34. Was it just a lack of knowledge about the tracks and their characteristics?

TheBennyB
05-05-2017, 05:51 PM
Think it had to do with transmission design and room to fit it as well.

Cooper
05-05-2017, 08:09 PM
With this all being said, why do some tanks have a front drive sprocket and some have a rear drive sprocket? Most tanks prior to 1940 had a front drive sprocket. The Russians were the first to use rear drive sprockets to my knowledge-T-34. Was it just a lack of knowledge about the tracks and their characteristics?

Tanks also have suspension in the road wheels. Vs the top fixed rollers. I'm not sure but loading suspension may have been a thought in design.

Izzy
05-08-2017, 01:07 PM
As for trucking, dont the drive mechanisms weigh more, therefore for eight distribution they would choose which way too load?
Not too familiar with excavators either....