Combines Rotor Sweeps feedback

Bloody h...l ! what a mess! and I guess that is the least that can be said! Thanks for the kind compliments but we have only written about things that a lot of other people have come up with as well and like you "bob" we had to make our own way for many years. Now the business end of things! You were harvesting at the rate of about 20 tonnes _ hr or for Americans around the 700 to 750 bus plus per hour. This should be well within the capacity of the elevator which I think has a capacity of around the 1500 to 2000 bus _ hr on the R50's but I will stand correction there. If you have been harvesting in damp conditions for many years and have had a lot of rumbling and heavy thumping from the rotor, metal fatigue could have played a part in the thresher spiders coming apart or a thresher bar bolt breaking or coming out allowing the bar to let go. My own guess would be a problem that a lot of the earlier Gleaner rotaries had. The cogs that drove and timed the seperator rolls will sometimes strip their teeth. On the R 62, 72 series, the later ones came out with a much wider set of cogs to increase the capability of the cogs to take the drive loads of the rolls. We had a couple of teeth go out on the narrow cogs of our R62 but found them during the daily inspection before starting and saved our selves some grief. At a guess there were problems here. The rollers slipped from their timing as some teeth broke out. The material from the thresher which was perhaps a lot more going down to the sieves than normal due to possible crop conditions, was not cleared from the cage area fast enough by the now out of time and momentarily jamming rollers. The material built up, blocked a fair bit of the concave and _ or cage and was rammed and packed against the concave internally by the bars until something gave. Having harvested aerial seeded clovers, this would be particularly likely if the material was a little green and tough. The rollers also may have jammed and triggered all of this plus maybe as you say, a slipping drive belt which might have been caused by the broken gears, again jamming and causing momentary belt slippage. The loading on the sieves may have been partly due to the slipping and jamming rollers which were failing to sling the material smoothly down onto the sieves allowing the fan blast to do the precleaning job. As well of course the sieves may not have been throwing regularly due to belt slippage and jamming. If this is what happened then more and more teeth on the timing gears may have been steadily stripped over some time which also seems to happen. All of this is just guessing from this distance but there is likely to be chain of events that just started with one small failure. Have a look at those gears and see if the teeth were all stripped suddenly or were they torn off one or two at a time which you should be able to see from the dulling of any breakage marks. The broken shaft and maybe that was also the initial failed component, can easily be checked by seeing if it has a more or less straight through break with fatigue crystallization in the break or the long tapered and twisted break of a torque or twist off type breakage. A straight through break means the shaft has fatigued and broken and precipitated the trouble. A twisted off shaft means look elsewhere for the problem area and it also means a very sudden shock and stop from jamming somewhere. If the combine engine started to load a few seconds before the breakage then it is even more likely there was a build up of material somewhere until something gave. You have my sympathy as the damage sounds pretty serious but it is only metal and can be repaired unlike a human being being seriously injured. Best of luck and we really envy you with those yields after about 3 droughts, one frost wipe out and the remaining years in our last 10 year run being semi drought. A really bad time for everybody around here. There are many around here who are about at the end of their stress levels and finance and just want out. Cheers!

Sounds like your on the right track. Beings you do not have adjustable seperator grate in that older machine you could make attempt at further reducing rotor loss with either stationary rasp bar in belly of seperator grate or fastening the old peg bars from old N series to outside of cage. I'd have to ask what was overloading tailings. Sometimes to much air will push to much clean grain to rear of sieve and then drop into tailings. Opening up sieve should also reduce tailings. If sample gets dirty with unthreshed crop you would have to tighten concave assembly, tighten front of concave or run more filler bars in front of concave. I assume you have tailings returning to feed chain area for rethresh. I have heard of air being turned as low as 4 for best shoe performance in wheat. You'll have to figure out what could be allowing chaffer to close up on you. It would be fun to know when concave eyebolt disappeared or frame member broke. It's hard to know what happened first. If eyebolt loosened up and backed down it could put undo pressure on frame. If concave frame has never been replaced on that early machine is has a half moon cut away area where I assume yours broke. This cut away or weaker area was eliminated on later concaves and could never bend or break. We broke some early concave hear when having trouble flowing edible beans at extremely low cylinder RPM. Wouldn't of been a problem if we had had sweeps figured out by then. I would have to believe you had weakened area there from previous setup. If that frame breaks there it will stress and break eyebolt area. Now it would take some real detective work to figure out your major failure. I'm thinking bolt holding bar on got loose or plain snaped. Early machines had what I call whiz lock nuts and bolts. They have shoulders on them with locking grooves built into shoulder. There was a campaign back in them days to replace all this hardware for there was some bad fragile bolts. I had even caught a couple of these with head of bolt missing but bar hadn't come off yet (very lucky). I also had the head come off a couple when torqueing. I had since threw all that style hardware and went with normal grade 8 with lock washers. I'd assume iron went down threw distribution auger and tried getting threw accelerator rolls and that is what caused problems with them drives. On them early R50s we added a second idler to get fuller wrap of chain around sprocket on distribution auger. This provided much more reliable and positive drive. I don't think your changes have caused the problems. If I read the failures right I would believe them parts were subjected to more pressure when having trouble flowing straw prior to upgrades. I think when you iron out a couple of these things you'll find you have even more capacity. Are you finding you are using up horsepowerIJ I hope that all made sense. If not I'll sure try clarify.

I will definitely defer to Dan's opinion here as he has seen these sorts of problems before. I decided to have a crack at the cause of the disaster rather than just sit back and wait for somebody else. Anyway Dan is far too polite to mention that I was on the wrong track. Thanks Dan. Best opening rains down here in west Victoria in Oz for maybe the last ten rather horrible years of dry and drought so we have got our tails up a bit higher with a chance of a reasonable season coming up at last. Cheers!

You really started me to worry when I first read your comments over quickly. I read defer as differ. That little work can make a big difference with you comment. I wouldn't feel bad about your take on disaster. I do believe if his problem started lower than cage the crop would still flow properly to discharge. One exception is if roll shaft had broke the chopper would of quit which would load cylinder very heavy. It would help to know if material was packed very heavy under cage or if cylinder was plugged very heavy all the way threw. I am very happy and or lucky to only have a couple failures like this over all the machines and years. A couple notes hear are we are talking about a twenty year old machine and it is very first year of P3 systems. That R50 is kind of a cross between N6 and l3. The R62 that came along a few years later is what was refered to as the fat 50. Drives were refined and everything wider than the 50. We did find a couple of the weak spots in the 50s but they mainly showed up when tring to flow the resistant to flow edible bean straw at very low cylinder RPM. This is how I can kind of relate to Bob's problem. My best quess is his concave frame failure was still of the original design. We had replaced most of them concave frames many years ago. The only reason I can think they originaly had a cut away where I assume Bobs broke was for the early original proto types in large P3s needed the cutaway to clear distribution auger. The P3s didn't come in large machines until 1990 and with the reposition of concave for the R62s the cutaway was not longer needed just like it was never needed for the R50s. This is getting to confusing so I better leave it now. I'm excited to hear you may be breaking out of the drought. All the best to you and everyone else over there going threw the tough times.