Situation or Problem
It may be difficult to achieve the desired seed meter accuracy with the seed disk currently being used and the crop being planted.

Summary
Seed disk selection is very important to optimize the performance of a vacuum planter. Follow these steps to ensure the seed disks you use best match your seed size and shape.

Solution Steps

Where to start? The easiest way to determine the proper disk is to place a sample of the seed into the cells of the seed disk. If two seeds easily fit in the cell, a smaller disk should be used. If one seed does not fit properly in the cell, a larger disk should be used.

What if two disks work? If two disks work well for a particular seed size, use the disk with smaller cells or holes. It’s much easier to increase vacuum to compensate for skips (and rough fields) than to lower vacuum to eliminate doubles.

What about difficult seed sizes and shapes? Some seed sizes or shapes may require a vacuum level that varies from the operator's manual settings. Verifying vacuum levels with an in-field check or on your John Deere dealer's seed meter test stand can determine the correct vacuum level for your seed. In some cases, the best seed disk for difficult to plant seed size/shape may not be a common disk used for that crop. Here are some situations and seed disk alternatives (part number): Small soybeans:  Acid-delinted cotton disk (A56251) Small cotton:  Small edible bean (Flat type) disk (H136468) with double eliminator Small sorghum:  Small sugar beet disk (A51712) or medium sugar beet disk (H136445) Field corn:  ProMax 40 Flat disk (A52391) with double eliminator

The flat disk concept The flat disk metering concept utilizes higher vacuum (12- to 22-in. of water depending on disk/crop) and a mechanical double eliminator to cover a portion of the seed disk cell to remove doubles that occur with the higher vacuum levels. John Deere has used this technology since 1992 for edible beans, but many other crops can be planted with flat disk should conditions require them. Two of the main advantages of flat disks are their improved performance when planting on hillsides and improved seed metering of difficult to plant seeds sizes/shapes. Due to the higher vacuum requirements, some 12 and all 16 row machines require 2 vacuum blowers to develop adequate vacuum levels for using flat seed disks and provide uniform vacuum levels across the manifold. A new vacuum gauge will be required for vacuum levels above 15-in. for machines equipped with a 0- to 15-in. gauge. NOTE: The double eliminator is compatible with MaxEmerge 2™ vacuum units built after 1992 and all MaxEmerge Plus™, MaxEmerge XP™, and Pro-Series XP™ vacuum units. It is not compatible with the dual inlet vacuum meter produced before 1991.   See your John Deere dealer for more information.

Affected Equipment

1700 planter

1710 planter

1720 planter

1730 planter

1750 planter

1760 planter

1770 planter

1770NT planter

1780 planter

1790 planter

DB series planters