I think I can add something to this discussion at least on the belted steel grouser side. Though I own some steel ladder tracks, I really have no real experience with them.
Belted tracks I can speak to. Got my '77 in '83 and have rebuilt the tracks in many ways several times in that time.
My '77 1742 originally had 28" wide tracks that consisted of four 4.5" belts and 32 grousers. At some point Tucker decided that they could open up the grouser spacing just a tiny bit and get away with only 31 grousers. That was cool, because after a replacement of all the belts all the way around, I had an extra 4 grousers.
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There's been an evolution in grousers too. As in all of the 28" tracks I've seen, my original 28" grousers use 8 bolts, 2 per belt, to attach the belts. They have the center 2 bolts welded in as they're inside the bracing at the center of the grouser. Later grousers had 4 or, later, 6 bolts welded in as the bracing got bigger.
Another evolution was the transition from using 70 (?)-degree angle iron to 90 degree for the main member of the grouser. The 6-bolts-welded-in style, I think, came in with this style.
The rusty '78 1744 that is my parts cat came (from the factory, I believe) with grousers that were made from square 2" tube. They had no sidehill cleats at all. Tucker also made belted tracks that they referred to as tundra tracks that put the belts to the outside of grousers which were made of 1"x2" flat steel bar.
Backing plates for the belts have evolved too. My original ones are made from flattened tube. At some point the tube they used got larger in diameter - the backing plate got wider. Then later they went to a backing plate made from formed flat plate.
And then there's discussion of sprockets. My original sprockets are 7-tooth, pointed tooth style. Sometime later Tucker introduced the 7-tooth, square-tooth sprockets that I recently learned came in a standard (1 3/4"?) and a 2" (thick) version. One variation of the pointed tooth sprocket had a gambrel (barn)-shaped steel core, a variation on the one-pitch point of the original.
But wait! There's more. Tucker also built cats with 9-tooth sprockets. I've never seen one of these in person, but from the photos I've perused, it appears they're pretty much using the same grousers as the 7-toothers other than they've cut away one end of the center plate (the widest part of the grouser, front to back) that rides on the idler wheels to allow the closer spacing of the grousers.
I'd take pictures of all of this, but my 'cat's 12 miles away. At some point...
BSkurka said:
<What is the difference between the belted track and the Terra Track?
Belted tracks use seperate belts and grousers bolted together with bolts. They have a connectors that allow taking the track off. Terra tracks are like big, burly snowmobile tracks. They're endless, and so require multiple movable idler wheels (both ends of the track carrier, unlike only one end of the belted type carrier) to create enough slack to remove the track.
Terra tracks come in several tread patterns. I've seen a pretty aggressive "grouser" pattern that looked similar to my steel grousers. I've also seen a nearly smooth 'tundra' pattern.
Someone suggested that the Terra tracks are "all rubber". I'd suggest that they've got to have some kind of internal stiffeners molded into the rubber, most likely steel.
Eric L said:
<I see yours has the older "slider" along the top to guide
<the track, anyone have an idea when they eliminated
<that and went to the 2 extra bogies on ea. side of the
<sprocket?
I'm not sure when the damper wheel system came in, but I think it showed first in the smaller cats sometime in the 80s - the 1300 series - where the shorter 4-wheel carriers would make it easier to make it work.
I've never run a damper wheel cat, but from what I hear the tracks are MUCH quieter than the slider type.
Sorry about droning on so long, but well...once you get the pump primed, sometimes it doesn't want to shut off. I could go on about track carrier differences/evolution, but I've gone on long enough without some photographic backup. More to come...