Combines Seive distribution IJ

[Old_Pokey]

Ok, so when you were looking inside at the seive did you take the left side concave door off and check the load on the conveyer augersIJ If so, did it appear that the material started to load the augers way up frontIJ Without knowing a few more details I'm going to say if it was me, first I'd try blanking off the first concave. Then if that made a difference but still not quite even, I'd go next to slowing the rotor down slightly to say about 1000 rpm. What I'm thinking is that when you tighten the concaves they dont just go up, they get tighter in on the left side. Making them pinch the grain harder on the left. Now at that kind of rotor speed the grain is threshing out too much too soon in the system. The grain is pushed out through the concaves that are pinched heavy on the left side. If you can get it to stay in the system a bit longer so it can sort of stableize with straw and do its seperating a bit closer to the grates where there is no offset pinch point, it should load more even. If that gets close, but you see a bit more cracked kernels than you like, you can blank part of the second concave and slow the rotor even more. Without knowing how hard that variety threshes in your climate, I suppose you probably have to keep the concaves tight. Thats what I'd do if its kind of damp like you say. I built a concave adjustment sytem for the right side of my machine to help avoid the left side pinch problem. If you want to see it I can email you a picture if you post your email. Again, I dont know quite enough details to really know where the problem starts, so I'm just kind of going by the info you gave.

 

[Old_Pokey]

Ya, it should make some difference. It depends on how loaded you are running now. The cut height makes a difference too. When the wheat threshes easy and seperates good with acceptable loss, I've ran our 1680 rotor as slow as 700 rpm. Sometimes lower if I cant keep it full due to crop conditions. For me it kind of fools the rotor into thinking its full by stuffing more material into the rotor per revolution. Of course, usually I run both front concaves blanked when these conditions exist. Once the rotor thinks its full and the distribution on the chaffer is good, its easy to set the rest of the combine accordingly. left side distribution is a tough one cause every thing you do to solve it always requires you to make changes elswhere to make up for the first changes you made.

 

[Mike]

Old Pokey what year is your 1680 and the reason I ask is because on my 1660 there is an adjustment on the pipe the concaves hang on that enables the operater to change the pinch point on the concave. IH put out on update with a measurement on the draw bolts to change the pinch point from the 6th bar to the 8th bar (if memory serves correct) to try and more evenly load the augers. Also with the system you built at which bar would you try to set your pinch point and why.

 

[Old_Pokey]

Mike. Ours is a navistar powered converted long seive. It had the updated adjuster but for me it is not sufficient for doing experiments on the combine. There are many different concave configurations out now days and some that we'll never see because someone built them for they're specific needs. We own several sets of concaves and some I have modified. I'm currenty working on my own setup for small seed legumes. My adjuster allows for side to side adjustment either individually or together. It allows up and down adjustment either individually or together. And it has the ability to lower the whole right side over 3" to clear a wet slug, while still maintaining the other settings. Sometimes in windrowed turf grass that gets rained on, the slug will get caught on the right side of the concaves and when that happens there is no way to rock it or removes the concaves. You're stuck using a pair of needle nose pliers and a bale hook to clear it from the right side of the machine. As far as what bar to pinch, it depends on the concave configuration and the material you're dealing with. Every combine is different as well, causing yet more study of the problem before making an adjustment. My theories, which are not for everyone, are that the tighter you run the concaves the more eliptical shape the concave needs to be. When you raise the concaves and they start to move more to the right, you create a low pressure spot rite where the material leaves the end of the concaves and trys to join the transport vanes. The material, depending on what its condition is, can stall there and cause some roping effect. What I do then is cut the first few bars off the concave and put a plate on them to act like a cage extention and then move the concaves to the left a little at a time untill I get the results I like. If you want to see my setup, I will happily email you a picture and then we can talk further about it so you know then what I'm talking about.

 

[George_2]

Brodale: I set our 1660 to the factory setting for soft white Superior variety wheat. I finished up yesterday but throughout the harvest I had difficulty getting any better than 16% moisture. I used the factory settings with 900 RPM on rotor and 850 on the fan. The only thing to combat the tougher threshing is I set the concave to 1.5 on the indicator instead of 2 on the indicator. It thrashed well with very few unthreshed heads. The monitor didn't indicate any thing significant went over the sieves. From that I would recommend you slow the rotor down.