My brother tipped over his Cat 307C last summer - the first "real" excavator Cat makes with steel tracks. Within minutes of it happening (coincidentally alongside the road), a couple of guys with a Kubota rubber tracked mini excavator came along and simply attached a chain, backed up, and tipped it back upright without struggle.
I wouldnt see strength issues with using a rubber track machine as the basis, unless you start modifying the rubber track gear. Personally, I would rather invest the money in refurbishing a smaller older steel track machine. I suspect you will come out money and machine ahead doing so. Having worked on quite a few rubber tracked machines in the past, I would still rather own steel tracks. Steel tracks last significantly longer, are easier to work on, and have some residual value (scrap) after the track is worn out. They also will not stretch nearly as quickly if you do any amount of real pushing with the machine.
You did say you wanted to push light snow or cut shallowly into loose topsoil right? If not, you do not want a hydraulic motor drive, period. On the mini excavators, the hydraulic drive motors typically are the weak point.
Last edited by justanengineer; 02-21-2012 at 04:16 PM.
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