- Aggressive furrow closing with self-limiting depth
- Creates ideal zone for crop emergence & rooting
- Rapid payback on investment
- Heavy-duty bearing with 5-yr guarantee
- Less mud adhesion vs. competitors
- Easily installed
- Fits most planters and gauge-wheel drills (see pricing
page for specifics)
No-till seeding is a relatively
new phenomenon, and more effective methods are continually being
developed. In the U.S. & Canada, most planters and "no-till”
drills are ill-suited to the task from the moment they’re built
(they were engineered for tilled seedbeds). For instance, the original smooth
closing wheels on all planters and no-till drills can overpack the
furrow, especially when soils are damp, causing poor emergence and
poor root penetration of the sidewall. Because of the soil structure
in no-till, the solid wheel is ineffective
at closing the furrow. To
avoid the packing problem, as well as the poor furrow closing by smooth
closing wheels, several
aftermarket companies began offering spoked wheels to replace the
original closing wheel.
Spoked closing wheels first came onto the no-till scene in the
early ’90s, and were often simply rotary-hoe wheels or
row-cleaner
‘spider’ wheels bolted onto the planter closing brackets.
This was novel and insightful. While these first-generation spoked
closing wheels were certainly improvements over the smooth wheel,
they had significant limitations. Rotary-hoe wheels often excessively
packed the furrow sidewall (think of a sheepsfoot), and had some
issues with accumulating mud and stalks. The row-cleaner wheels
(when used for closing) had such long slender spokes that they
tended to lift the sidewall too much, flinging chunks of sidewall
in all directions, and sometimes roto-tilling out the seed (the
extent to which these are problems depend on amount of pressure
on the spoked closing wheel, soil conditions, lateral spacing
from furrow, and the degree to which the seed is embedded in
the bottom of the furrow). Also, the row-cleaner type of closing
wheel did no seed firming whatsoever, but luckily Keeton seed
firmers (and several small-diameter ‘seed-lock’
wheels) were introduced to the market about that same time.

By the mid-’90s, at least one spoke design was specifically
created to provide the closing action demanded by no-till conditions.
This design had spokes with a fairly small surface area at the tip,
tapering sides of the spoke, and a shorter spoke length. Although
an improvement over the earlier attempts, the new design had problems
with durability, particularly frequent bearing failure, and with
mud accumulation due to the thickness of the spokes at their base.
However, the spoke shape was clearly an improvement over earlier
attempts at spoked furrow closing from off-the-shelf wheels designed
for other purposes.
Enter the Thompson wheel (in 2002), with unique patented features to dramatically improve performance. The thinness of the wheel allows it to easily enter the soil, for excellent breakage of the sidewall. The thinness is also what prevents mud accumulation on the spokes. It simply has nowhere to gather. The blunt tip & tapering sides of the spokes further assist in crumbling the sidewall. The tapering sides gradually increase the resistance the spoke encounters while operating in the soil. This limits the depth, as does the overall length of the spoke itself (considerably shorter than some other designs on the market). So you get just the right amount of sidewall shattering, without digging too deep.
Another reason the Thompson wheel was developed was sheer durability: we put a truly robust bearing into the T-wheel, as frankly we were weary of changing bearings in the predecessor wheels. The T-wheel’s monstrous bearing features a triple-lip seal, as well as our unique patented shroud to protect the bearing face from fertilizer and water. We’re so confident in our bearing arrangement, we guarantee it for 5 years.
Toe-Out Wedge Makes The Thompson Wheel Even Better
Exapta’s toe-out wedge creates up to a 6-degree angle to the direction of travel when used on the original planter tail-piece (closing bracket). The original bracket holds the wheel so that it is tipped from vertical, but runs perfectly straight with the direction of travel (zero toe-out)—this was to allow the original smooth closing wheels to pack the sidewall, relying on the tilled soil’s looseness to collapse easily back into the furrow. In no-till or other tough conditions, the sidewall may not collapse easily, and requires the slicing action of a spoked closing wheel. The toe-out helps all spoked wheels to more actively engage and gather soil from the fractured sidewall and pull it back into the furrow—sort of the reverse of the opener blades prying apart the soil while creating the furrow. (Note that the JD 50, 60 & 90-series single-disc drills, have closing wheel arms with a toe-out built-in, albeit for their smooth closing wheels.)
Exapta’s toe-out products are easily installed, and fit most planters, including 15- and 20-inch configurations.
Toe-out for JD 7200 / 7300 planters:
Since the Deere 7200 / 7300 planters originally had closing brackets with welded-in stud shafts onto which the closing wheel’s bearing slid, there are no easy options to achieve toe-out. The best choice is to update the entire 7200 tailpiece to one that accommodates wheels held by bolts (i.e., what all 1700-series have), such as Exapta’s PLT120740 (handle & bushings included, spring sold separately). Another option is JD's kit AA44266.
Toe-out for JD 7100 / 7200 planters:
Closing wheels on these planters were held with “waterpump-style” bearings having a protruding stem and held into the closing bracket with a roll-pin. To use Thompson wheels at all on these planters, the closing bracket needs to be updated to a bolt-type closing-wheel configuration, such as Exapta’s PLT120730, which also gets the planter converted to lever adjustment of the closing spring pressure.
Note: for all spoked closing wheel designs that do little or no packing, such as the T-wheel, it is crucial that seed firming be accomplished with a Keeton or seed-lock wheel. See Tech
Tips for Planters.
Coulters and strip-till influence the closing wheel decision: See Rethinking
No-Till Seeding.
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