OK, ya talked me into it and I've had my nap already. I started out on a Ford 8N tractor with a scoop in the back mounted to the 3-point hitch. Some folks called them a Fresno. Next was a Euclid S7, neat little machine, noisy and not too fast. Detroit 471 engine, Allison auto, hard hitch and a bouncy ride sometimes. Graduated to Letourneau D-Pull. About the same size as the S7, same engine, standard 5-speed tranny, and of course, electric steering and cable controls for the bowl. My brother and I owned four of these around 1967. Pushed them with the Cat D8 2U tractors. Very bouncy! Had a hard hitch.
After that, MRS (Mississippi Road Service) 110's and 200's. The 110 was a four-wheel drive tractor pulling a 14 CY hydraulic scraper. The scraper could be remounted on a fifth wheel axle assembly and pulled by a Cat D7 or 8, or in our case, a TD20B International dozer. The 110 tractor could steer the front axle, the rear axle, or both together for crab steering. Never saw any advantage to this arrangement for crab steering, but it scared hell out of the locals as we were highballing it down the highway. Anyway, This tractor had the Detroit 6V53 and it was a real screamer at about 195 HP. 6-speed Allison tranny and a hard hitch. These units would rock you to sleep going down the road, but were so crammed with high-tech stuff that they weren't very dependable. The scraper bowls made excellent gun pits in a firefight.
The 200 was a monster we thought, and I actually only ever ran one in training in Rhode Island for a couple of days. The tractor had a 450 HP Cummins, a thirteen-speed Road Ranger with a two-speed locking-differential, air brakes -- which could be applied by hand to the right or left drive wheels, and a drawbar that was rigged with a weight transfer device. The scrapers we had were hydraulic, but I've seen pictures of these creatures with a PTO rigged for cable. The weight device was used as you began getting a larger load in the bowl. With the big engine, you would lose traction easily, so you started applying pressure from the scraper hitch to the tractor drawbar. The more loaded the bowl became, the more weight you could transfer to the hitch. You could get real busy with these critters as there were more levers and things to use for loading, turning, traction, and unloading than one man could handle by himself, not to mention steering and shifting gears.
I used a 200 tractor with a standard 5th wheel dolly to pull a Rogers 50 ton loboy all over Northern I-Corp in Vietnam. If we could get it on the trailer, I could pull it. Steering was slow to respond, and my favorite tractor had a two-speed differential that I had to stop, crawl under, and shift by hand as the control was busted. We had one other one that was faster by about 5 MPH, the engine was set to a higher RPM, but my old girl was a real hog at pulling and would pass the other fella going uphill easily.
MRS built very large scrapers back when Cat was just thinking about getting into the business. I believe the largest was a double barrel unit running about 50-60 yards heaped. Never saw one in the flesh, but maybe some of the boys here have from down along the big muddy. That's where they made em.
The Army boys, and even the Vietnamese engineers, had the Cat 630M scraper. It looked like the 110 MRS, but we Seabees all drooled over them and wondered why we didn't have any. I never ran one. MRS made a smaller unit that the mud Marines used. It was about a 8 yard machine and used a 471 Detroit for power with an Allison tranny. By the way, all the machines I have described so far have been open or no cab machines, maybe just an umbrella and a windscreen. No seatbelts. No heaters.
I used a Cat DW20 for a few days in Rhode Island, but the Bees were phasing them out by then and I never ran another. Did use a DW21 some in Colorado, didn't like either one much.
There were a host of pull scraper manufacturers way back, you still see them in parks and scrap yards or along side the highway rusting away. They were all cable, and if you have ever had to pull cable through all the sheaves on the dern things, you will understand why they fell out of favor pretty quick when the hydraulics became available. The trick was to not let the cable break completely apart. If you were careful and took it easy, you could spool more cable off the reel and replace the damaged section fairly easily. If it busted in two, you were up for a dirty afternoon. You may notice some Cat cable scrapers with a wooden spool of cable parked up on the right front of the scraper draft-tube. That's what it was there for.
I ran TS14's in Texas south of San Antonio for HB Zachry. They were a fun little machine and would go anywhere. I still like em. These had the 471's front and rear with air-shifted Allison's. The thottle to the rear was air. Hard hitches and they flat would launch your butt in the sky on a rough haul. We pushed them with a single D9G pushcat when the operator was paying attention. The muck in the riverbed there was a combination of gravel, sand, and clay. The clay sometimes would roll into the bowl like a jellyroll, and it just curled up untill that 9 couldn't stuff another ounce inside the apron. Trouble came when we tried to eject the stuff. It was so heavy the ejector couldn't lift up.
OK, some explanation here. S7's, S14's and TS14's, S and TS24's, and all 32's all used an ejector that was a combination of ejector and bowl floor. It was hinged right behind the moldboard and it lifted up and forward to dump the load. Cats and others use a solid floor with a push type ejector on rollers that simply moved straight forward. Some Eucs used two hydraulic cylinders, one on each side, to lift the apron whereas Cat used a single cylinder with a dog bone and a banana link on top of the gooseneck to lift the apron. Some other makers used a similar setup, only with a cable instead of the dog bone link. The TS14's used this last style.
So, where was I, oh yeah! Anyway, dumping the 14's with a big roll of clay was tough. If it wouldn't dump, we would back up a bit, then charge forward with the apron wide open. There was a trick to getting the aprons to flip up and backwards out of the way completely that we learned to use, but the master mechanic didn't like us doing it. Well we'd charge forward, apron up, then hit the ejector for up and the trans shifter for reverse, all at the same time with full RPM on the engines and a hairy handed grip on the wheel and the ejector lever. Most of the time that roll of clay would just spool right out and we would make a hard 90 degree turn to the left or right to clear it. The master mechanic didn't like us pulling this trick either. But once in a while, we couldn't get it out and we would have to go over to where a Cat 225 excavator was working and have him dig some out. That was considered a great loss of face for us and we hated like hell to do it.
Shortly after that I went on to Colorado. Denver was doing a boom at the time and there were literally dozens of International 295 elevating Payscrapers all over town working on housing developments and highways. This is the first place I ever saw pushcats used behind elevating scrapers. The reason for it was that they were working on benches so high and steep that they couldn't even get up to the bench by themselves let alone load. The Cats eased them up and then stayed behind as the can loaded up. They didn't really push hard so much as just kept the pan moving gently. Most of Interstate 25 from the New Mexico line to Ft. Collins was built by these rigs.
I ran a TS24 for an outfit building housing pads and roads over near Morrison and that was a blast and a half. Euc scrapers were some of the easiest loading scrapers in the world, mostly due to the angle of the moldboards. Cats used a steeper angle and were harder to load, even when being pushed. The Eucs were much faster to dump too. The 24 had no cab and that was a cold winter and a late spring. I bought a pair of Air Force high altitude flight pants at Jax in Ft. Collins, and with a big ski parka and ski mitts, along with some Antarctic inflatable boots, managed to make it Ok without freezing too bad.
Paddle-wheel, or elevating scrapers, are an interesting device and the smaller units are kinda fun to run. 613's are a hard hitch machine and prone to bounce real bad. Early units used the 3208 boat anchor engine, and disc brakes on all four wheels. The brakes worked well, but in wet clay type soil, the rear wheels would just drag all over and the front wheel would spin like crazy. We learned to just go home when it rained. The calipers on a disc brake are designed to drag slightly, and Cat never figured out how to make them drag less so you could move the machine in mud or wet clay. It was an interesting year and I learned to extricate my 613 from almost every conceivable situation. I would teach these methods later on to 613 operators in several places.
After college, I wound up in Florida working for an AC dealer with lots of 260 and 460 open bowl and 261 elevating scrapers working all over the state. Most of those working in the Ft. Lauderdale area were 261's, and while there were a nice machine to run, they were a real b*****d to work on. These were all hard hitch machines and had a lot of transmission trouble. Believe it or not, you had to remove the engine and tranny as a unit. What a drag. The steel used in the elevator paddles on these machines far outlasted those used on the Johnson scrapers being sold by Cat at the time. Some of the 460's had the GM engines, and some were using the newer Buda/Allis Chalmers.
Well, I'm up to the limit tonight, got to go.