Combines For MinnR62 from below post on11 12

So are you saying that the staggered bar design of sunnybrooks isnt very desirable in cornIJ I havent been around an enclosed rotor but next year we will probably go with two CDF's or maybe one of st johns. I like how your bars go out all the way, I was also wondering about the sweeps verses the vine knives. I ran a 9790 in green stems and I assumed the vine knives are what really gave it a surplus in capacity. I also noticed this year in some of the drought corn with smaller ears we tended to have more cob break up with the standard rotor and more pieces in the bin. If we were in large ear corn the standard rotor did a nice job, although we have pulled every other cylinder bar off

I'm passing on our experiences (and those of a few others, as well)concerning feeding into a misaligned setup. This also applies to IH specialty rotors (and a little more so, actually)with their short rotor bars -- ears of corn will wrap around those mounts and break even somewhat worse. That's the primary reason our host Marv Gorden developed his IH rotor bars -- to close up the space between the rotor bar mounts and roll, rather than bend the ears of corn. In the 9790, the vine knives may have an effect in very tough stems -- there's no question that they'll grab a stem and either carry it or cut it. However, I think it's more likely the fact that this rotor has P3 bars installed on it. We've been modifying these rotors with these bars for considerably longer than AGCO has been producing the 9790, and so far, we've never installed more than 9 rotor bars on any of them. We use a much different spiral type arrangement for rotor bar mounting, but on our rotors no operator has ever used vine knives. I will say that on the 9790 with the abundance of rotor bars installed in rows, that the vine knives may have a little more effect - may be breaking up slugs caused by straight rows of bars. This rotor is enclosed, and is 14' in length, allowing material to spread out much more evenly (at least the way we do it)and separation area of the concaves and grates runs about 80% of the full length of the rotor -- that's about 4 1_2' more length than R series Gleaner. Also, the front beater and auger arrangement spread out incoming material somewhat, and initial loading is more even than in a more conventional machine which has to take whatever slugs_bunches come up the feeder house. Difference between vine knives and sweep_agitators probably can be best explained by the differences in rotors-- On the CDF rotor, bars are mounted tipped forward and on the full diameter rotor mount_bar combination has a 3 1_2" depth -- the bar angle pushes material to the concave surface in a pinching effect and the depth of the mounting allows a little buildup -- the knives help to carry this buildup. On the flat bar mounting which we favor, the leading edges of the bars carry material and the depth is 2 1_2" to the top of the bar_mount combo. This has more of a tumbling effect than CDF and the material is pretty much spread automatically -- also the leading edges of the bars are muchmore aggressive at carrying thru. The sweeps are provided more as devices to agitate and change direction (more for providing separation) over the grate than to push to the discharge, although they do provide some of that effect. Did you have 1_2 of the rotor bars off in your drought cornIJ Usually it's a matter of loading when cobs are breaking up. More cylinder bars on the rotor at any RPM reduce the load and the crop is forced to thresh against the metal workings as opposed to threshing against itself -- also, small diameter ears have more of a tendency to drop between concave crossbars and catch -- won't roll thru. If you had rotors bars removed, it may have been a matter of ground speed, but it's also possible that due to header operation, you may not have been able to maintain proper speed --not unusual in droughted crops due to flimsiness of stalks_stems. Can you email meIJ -- I'd like to point out something else.

Terry, Have you ever tried widening the spacing between helicalsIJ Wouldn't it be best to have spacing at length of most common cobsIJ New chrome helicals will clear 25" cylinder by only 3_8". Forward tilted bars running at 25" diameter will wedge most average size cobs hard into channel helical which will likely break some cob upon leaving concave or seperator grate. CDF with its reduced diameter cylinder increased this gap to helical which reduced the broken cobs even though bars are tilted forward. Your cylinder with flat mounted bars would more likely push cobs along without wedging against helicals. leaving cylinder bars off and or using my sweeps on 25" cylinders both seem to reduce broken cobs by either less hits from bars or keeping them cleared away. Reason helical clearance hit me so hard it because of a R60 with P3. They have helicals very close together in transition area and most all cobs have to go threw there. I think that area may have been operatating as a cob grinder. There is basically double the helicals in that area of early large P3s. I think even the newer P3s could be spaced another inch or so wider so more cobs could roll along without damage. What do you thinkIJ

Yes, Helicals can be spread out more than they are now, and especially in the newer machines. In the older machines if cobs were breaking up, we'd remove 1_2 of them starting next to the concave, and would sometimes remove the add-on transition kit, as well. Then we'd add a couple of short pieces of 1" channel iron crossways between the helicals next to the discharge to stop rotor loss. This effectively stopped cob breakage and cleaning shoe didn't have little cob chunks sticking in the chaffer. Problem was that this was only good for corn -- if you wanted to cut beans in about the same time frame, you had to reinstall eveything. Made for a lot of tinkering and cussing. Difference is that corn cobs, as opposded to other crops, when left whole, will pretty much sweep the cage, and as the load loosens coming over the top rear of the rotor, gravity will affect the load and grain will tumble loose. I'd bet it'd look pretty much like a mixmaster -- tumbling until the load is heavy enough to carry over. I think that sweeps installed on a rotor (and especially as you build them for open rotors),produce a separating effect as well as carrying to the discharge. As they push trash, it's evident that they also push material against the backside of the helicals, providing a mild retarding effect -- helicals provide this on the leading side also, or they couldn't assist in feeding -- all this means that they're more effective. It's likely that there's a helical_sweep combo which would be good in all crops_conditions, but it would probably take several years to find it.

As tj says, the seperator sweeps look as though they force material against the backside of the helicals. The included angle between the rotor sweeps and the helicals is only about 40 degrees which gives a shearing action to anything caught between the sweeps and the helicals. Could helicals made out of, say 3_4" round bar in the separator section help overcome any break up of cobsIJ Round bar helicals in the steep pitch mode might work even better with the sweeps in corn.

An addendum to my above post. We have not used our sweep equipped rotor as yet but will start our harvest in about a fortnight so it will be interesting to see what happens. looking at the way the sweeps are set up, it seems to me that the whole operating principles of the rotor in the separation section have been changed. The helicals were used as the main means of moving the material along in a controlled fashion. The rotor bars did not make a great contribution to this movement. With the very aggressive sweeps installed, the rotor now becomes the main mover of material with the helicals playing a controlling roll in the speed of the material moving through the separator section and slowing the material down from the aggressive angles on the rotor sweeps. Taking this approach, the design, angles and characteristics of the helicals may need to be changed quite radically. The angle of the sweeps on the rotor may also need rethinking, possibly with the sweep angles reduced to give more turns of the rotor, ie less pitch as per auger flights, to move the material through. I don't know the answers but toss these thoughts up for some discussion.

Thanks for that. I just couldn't figure out what could be breaking cobs so bad in that early P3 ('90 and '91 R60-70's) while later P3 (R62-72's) were so much better. I'm thinking I will try spreading helicals one additional inch and maybe even take a look at angle iron helicals. Angle iron will gain me another inch inbetween helcials without changing spacing. I don't think one inch will affect flow of other crops to any extent but will allow more cobs to roll threw whole. I think the use of sweeps does spread material between helicals nicely as well as keep it moving. Helicals not only keep material moving toward discharge but they also prevent material from moving threw too fast with sweeps. Machines are realy working so well with these different rotors or rotor setups that it is hard to go ahead and change anything. I wouldn't even be thinking about helical spacing but then things started to click when I realized all them closly spaced ones in that troublesome early P3. Thanks for your help. We'll see what we can learn next year. Have a good one

I think cobs will stay inbetween helcials with no further damage once they are in there. I don't think I would want round helicals (except for maybe just corn) for even rounded normal helicals reduce capacity to flow tough straw. Then again that all changes if sweeps are installed. I had thought of reducing pitch of sweeps if I was to redesign. I would mainly do this because angle is quite steep for the 1000RPM crops. They work great at the angle they are but I may be seeing more wear on them than if they were at less angle. I do want to sweep complete area of removed bars so I would have to add another sweep bar per assembly if I went with next shallower angle. We'll take a look sometime. Have a good one

Correction to above statement of cylinder bars clearing helicals by 3_8". Gleaner calls standard cylinder 25". I've measured cages rings and found them to be in 27 1_8" range. New chrome helicals will normally measure 5_8". If cylinder was exactly 25", cage 27", and helicals 5_8" high it would leave you with 3_8" from cylinder bar to helical. I got in and did some measuring today and find good condition bars to clear helicals by 5_8" and clear cage by 1 1_8". Thicker chrome on one or all these parts will bring clearances closer. I will some day measure exact diameter of cage and cylinder.

Dan: A new cage (or rebuilt) is 27" I.D nominally, but you can see very small variations from the rolling process or handling of the roll of maybe 1_64" or thereabouts.A cylinder with new bars is nominally 25" O.D. -- there you can also see small variations due to slight angle changes on mounts, thickness of metal, dimpled holes in cylinder spiders, different shrink rate of batches of molded bars. YOur measurements are pretty close. A cage will stretch a little over time until stresses from the rolling process take a set, so after it's been used for a season it will probably be a little oversize from original.