20" discs vs. 18" discs....advantages?

   / 20" discs vs. 18" discs....advantages? #1  

bilrus61

Platinum Member
Joined
Jul 1, 2010
Messages
537
Tractor
kubota 4200
Looking at a Keen Kutter disc here that has 20 inch discs on it. Most others of this type have the 18". Its a 6 1/2 foot disc and I think my 44 HP Kubota won't have any issues pulling it. What are the benefits of the larger 20" discs and should I let it sway me over another disc I'm looking at thathas 18" inch discs.
 
   / 20" discs vs. 18" discs....advantages? #2  
cut a little deeper if the disc is heavy enough.
 
   / 20" discs vs. 18" discs....advantages? #3  
The 20" disks are the way to go IMO. You would have the capability of digging 1" deeper, the disk will weigh more just because of the size and they might even be made of thicker material which would be adding more weight and strength. I would get the 20" disks if it were me.
 
   / 20" discs vs. 18" discs....advantages? #4  
Bigger rolling radius also allows the disc to walk over objects easier.


The biggest drawback of 20 over 18 is the cost.
 
   / 20" discs vs. 18" discs....advantages? #5  
For us in the north east an 18" blade is small and it would make the disc more prone to bearing and axle trouble do to the stones. The larger diameter blade will normally walk over obstacles better. You could say you would gain weight as well as life!
 
   / 20" discs vs. 18" discs....advantages? #6  
If you get into soft soil or sand the blades could sink far enough to drag the axle through the ground. It puts a tremendous strain on the tractor. Multiple passes will do the same in muddy or wet ground.

Go with the larger blades. They will wear down soon enough anyway.
 
   / 20" discs vs. 18" discs....advantages? #7  
The larger diameter disc blades are more aggressive, however, they leave a little rougher finish. A drag behind the disc should take care of that issue. Ken Sweet
 
 
 
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