Farm Equipment - Cylinder/Concave Terminology ??

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Cylinder/Concave Terminology ??

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Category: Allis Chalmers
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URL: https://www.allischalmers.com/forum/forum_posts.asp?TID=177906
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Topic: Cylinder/Concave Terminology ??

Posted By: FREEDGUY
Subject: Cylinder/Concave Terminology ??
Date Posted: 28 Jan 2021 at 6:12pm

Are the Gleaners and the 66/77/88 series Deere's considered the same parts as far as "cylinder/ concaves ? There's a guy on AT inquiring about an 8820 concave (singular) replacement like it's a single unit ?? I think of a Gleaner as "multiple" bars that can be replaced/maneuvered for different crops ??

Replies:

Posted By: ryan(IN)
Date Posted: 28 Jan 2021 at 6:27pm

You are thinking of like an F gleaner that uses different bars called a closed concave. A L/M gleaner and the N/R/S combines use an open concave like a 66 or 7720 Deere.

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ryan
1984 8070 FWA,1979 7060,1975 7040,1971 190,1960 D-17D,1957 D-14, 196? D-19G, 1975 5040,1971? 160,1994 R62

Posted By: DrAllis
Date Posted: 28 Jan 2021 at 6:28pm

Gleaner L and M series similar to the Deere models mentioned. Concave is one piece and open for grain to fall thru.

Posted By: FREEDGUY
Date Posted: 28 Jan 2021 at 6:37pm

Thanks. So there are no "bars" to be replaced in a M/L machine ?

Posted By: DrAllis
Date Posted: 28 Jan 2021 at 6:50pm

There is one channel iron on the rock door and one immediately behind the rock door on the front of the open concave.

Posted By: SteveM C/IL
Date Posted: 28 Jan 2021 at 9:53pm

and on the conventionals (less M&L) there is a "concave door". The door gives lots of options for number, placement and style of concave.

Posted By: Ray54
Date Posted: 29 Jan 2021 at 3:10pm

Concave and cylinder 2 different parts you need both to thrash grain. Two basic types of cylinders a spike tooth and rasp bar. I would need to dig the parts book out, but I think L and M Gleaners could be had with ether. The spikes or rasp bars are replaced before the concave. The concave is a grate and holds the heads up until the bars break the heads up and they fall through the concave. The gap between the cylinder and concave is adjusted as well as the speed of the cylinder to break up the grain heads( seeds off the rack or cob).

The concave and cylinder more or less unchanged from the first thrashing machine until the the rotary concept came along.