I have about 5 acres I mow every week.
Currently I have a JD1600 WAM to do most of it, it takes about 3 Hours.
I'm tired of not being in a Cab, and want to consolidate two machines
(JD5425 Tractor and the 1600 WAM) into a 4520 with a rear mower and
eHydro to reduce maintenance costs and get more use out of the Tractor.
Most of the land is pretty flat with some sloped areas, and about 1/2 mile of
roads that I like to cut the grass beside for a few feet, which is easy to do
on the WAM as the side deck articulates about 20 Degrees.
My question is if I get a 90" Flail with 26" offset and Top and Tilt, will I be able to
cut the sides of the road (some of the sides slope at at say 20-30 degrees) easily?
What are the downsides of the offset mower?
How fast will I be able to finish mow with a 90" Flail on the JD4520 (50 PTO HP)?
Would a grooming mower be faster?
Will I destroy a flail if it hits some gravel on the driveway?
Is the JD 390 Flail Mower any good?
I want to welcome you to TBN as new member,
Mowing with a mounted stationary offest mower of any type requires you to be more diligent in paying
much more attention to the location of obstructions like trees, fence lines and building foundations thats all.
A top and tilt will not help much at all with a flail mower as the rear roller is the
"actual" height adjustment point and method for a flail mower unless it has
front wheel casters as well.
You will not destroy your flailmower if you hit some gravel,
You will ding the knives a bit and make lots of noise.
This only happens IF:
The rear roller mount(s) breaks and drops off while mowing and as
result the flail mower rotor drops and the flail mower knives start digging
as the rear roller is no longer there to regulate the mowing height.
OR the top link is so loose that it allows the flail mower to fall forward in
a shallow ditch or swale you are crossing.
while mowing.
Are you planning on mowing from the shoulder of the road OR traveling along the slope of the ditch
to mow?
My first question is how wide is the slope in the ditch from the edge of the shoulder to the bottom?
If all you want to do is simply mow back the first couple of feet of grass you will be fine.
My second question:
If you intend on mowing the slope My question is how deep is the drainage ditch and can
you safely realisticly mow the slope with the width of the tractor?
If you can widen the rear wheels and have loaded tires you could do it but the angle of the
slope is the issue as mowing along a slope is safely done up to 15 degrees.
The John deere 390 is a finish flailmower and going by my experience with both mine
and my fathers past experience with the JD 25A on his Ford Jubilee the quality of build is excellent.
As long as you clean the dust from under the belt guard to keeep the grease fittings exposed and grease
the fittings regularly and do not over grease the flailmowers rotor bearings(6-8 pumps every 10-12 hours of operation)
remove the belts in the off season and put them in a sealed garbage bag to keep them from rotting
you will have mower that will outlast your tractor(s)
As far as mowing speed you will be able to mow as fast as the conditions allow you to.
The slower you mow the better the cut and finished look and the finer the grass and brush clippings.
The The JD 390 flailmower will be a very safe mower to use as anything it hits will not be thrown
hundreds of feet as would happen with a rotary cutter or grooming mower of any size.
The if the flailmower encounters a rock in the ditch or garbage the knives will fold back and away
from the object and the object will remain under the flail mower hood until it passes over it.
The Vertcut method of mowing is very very very safe methid of mowing around 2 and four
legged rug rats and along road sides/verges etc.
The nice thing about a finish flail mower of any brand is that once you get the grass mowed down to
the height you want to maintain it takes very little time or fuel to keep up with your mowing and the time it takes as the
mower cuts much more efficiently with many more inches of cutting exposed to the mower width versus
a rear mounted rotary finish mower of rotary cutter which only uses halts cutting width to mow an any time.
You will not have any down sides with this purchase and the side slicer knives and knive hangers are not expensive.
I forgot to add the JD 390 flailmower gives you a built in lawn striper at no extra charge too
and the JD 390 will give you a beautiful cut on your lawn as well as the rear roller aids in
maintaining a flat cut along its entire width.
