Value of the forward return pan under rotors

The step from auger beds to grain pan made a huge difference, grain pans make as much difference because of how evenly they drop the grain and chaff to the sieves as much as dropping it pre-sorted(I think). The augers would drop in bunches and most grain pan designs incorporate a air blast at the drop from the pan to the sieve. Taking grain/chaff to the front so it has the full pan to stratify could be good, but I see several potential problems:
-Crops with green material could gum them up and cause flow issues.
-Concaves aren't going to be easier to change.
-If operating in hills(maybe no issue for you) there could be a buildup of material if you don't have enough slope on the pan and could lead to wild swings in actual distribution rates onto the sieves.

It's hard to argue with the good reviews of some of these newer combine designs, but those features were designed into the machine. I'm not sure that doing this to a CR would make much more than a incremental gain, and probably not under all conditions. If you do something please report on it though!

Just the back half I believe.

I wondered when this was going to come up.
I, like just about everyone else who knows a bit about harvesters, have always been told that single rotors load (the cleaning system) more on the RHS than the LHS. And this is true in most instances.  However, there is a very strong argument - coupled with proof & experience - the loading onto the grain pan/cleaning system is VERY MUCH INFLUENCED by concave position, rotor speed & crop conditions.  
Firstly, the position of the concave relative to the centre of the rotor has a big influence. “Level & centre” of the concaves in a Case flagship is extremely important.
Secondly, after the level & Centre is correct, the amount the concave is open greatly affects the distribution of material on the grain pan & then the cleaning system..  Tight concave will load on the RHS. Open concave will load the LHS.
Thirdly, high rotor speeds will move distribution to the LHS.
There’s a great Case video on tube that clearly shows this affect.  And anyone can see this affect via the loss numbers when you move the concave up or down whilst harvesting.  5 mm’s either side of optimum is very noticeable.

Now, to throw a spinner in the works.
’50 series Case with HarvestCommand changes the distribution …… I expect by the position of the fixed & moveable vanes.
How do I know this?

I’ve got a Gen 11 MAV fitted to my 50 & the material deflectors that are on the back of the internal chopper/beater floor are designed to point the exiting material from the rotor, more towards the middle of the MAV chopper (from RHS more to LHS) ….. for even chop & spread.  This is/was absolutely the fact with the same type MAV on my 40 series.

This is absolutely not so with a ‘50 series with HarvestCommand.  The exit point of material from the rotor has changed & definitely goes towards the LHS.  You have to point these deflectors to the RHS to even up the chopper spread.
I’m not “the only one” who’s noticed this fact.

So I’m thinking, the ‘50 series with HarvestCommand is also loading the cleaning system more evenly - via influence & affect of the vanes - as the 50 has definitely more cleaning system capacity than the previous models.  Unless they’ve done something else in the cleaning system - of which I can’t see as yet - vanes & therefore more even distribution has made a very big improvement here.

Therefore to get back to the subject at hand, is a grain pan required for rotor material returning to the main grain pan or just better more even loading of rotors/concaves ??

Yes I've read your reports before Rod. Many thanks for posting such detailed notes over the years. I did adjust the concaves to be parallel to the rotor, as described in the manual and by your helpful instructions. Also we've spent all sorts of time trying rotor speeds and concave settings, all to no avail. Sometimes it helped most of the time it didn't. We did quite a few stall tests this fall. I think the reason adjusting the concaves doesn't help that much is the overload isn't coming from the adjustable modules area, and if your wheat is threshing easily (as ours typically does), it's virtually impossible to stop over-threshing. The material then is coming from the back half of the rotor where there are no adjustments for concave clearance. Which is what this idea of carrying the material to the front of the pan would perhaps help with.

Of course adjusting the rotor vanes will likely help, but until I can get the adjustable vanes on my machines, this is too difficult to do, especially if you need to adjust it several times a day.

The right side overload issue is not specific to Case IH solely. All single rotor designs that I'm aware of have this problem to one degree or another.

Isnt the self leveling system sealed up much better airwise on 50's or was that done already on the 40's? So air cant escape out the side on exaggerating poor distribution? I know people that have installed the "Rochester air seal kit" on older combines have nothing but good things to say other then tedious a install.

Murray from mad concaves has very good setup videos on YouTube and he said from all his testing with adjustable veins he said leaving them on fast alway worked best for him and adjust the other variables to suit

I can see how better sealing would lead to easier setting of the sieves, and no doubt makes the Harvest Command work better. But I'm a bit skeptical that it would solve the right-hand overloading issue. Even with all the leaks, the CaseIH fan has plenty of air and to spare. I don't think NH uses the cross flow fan, and the rest of the sieve system is otherwise identical.  Perhaps if one could adjust the left vs right air independently that might help.

I've heard very mixed things about the full automation package on the red machines. Some people, such as yourself, find it makes a huge difference in all areas. Other reports from here in western Canada don't show near as much improvement and one person felt like there were no gains at all in canola. Theoretically it can pay for itself in gains.