Re: [Brushcutter] Need trimmer head for big cords

Michael Uplawski <michael.uplawski@uplawski.eu> wrote:

Good morning from France
 
I need a new trimmer head for a Honda 435 UMK-E (four-stroke)
brushcutter. My favorite cord size is 3mm. I can look that up in
inches but do not really want to. Let's say big cords, the bigger
the better.
 
The problem is not that I do not find any.
 

What are you cutting, and what are the obstacles?

Three millimeters is very close to one-eighth of an inch,
or .125". The heaviest cord I've seen in the US is .093"
I've a  spool of .093" Echo cord with four longitudinal ribs
having sharp corners that cuts quite well on any but woody
material. I suspect most folks use a saw blade if .093" cord
won't cut acceptably.

Speaking of which, a portable circular saw blade of about
7 inches works wonderfully. Cheaper than dedicated brush
blades, fairly durable if carbide-tipped and less reaction
than either brush blade or .093" cord. I used an Irwin 24
tooth 7.25" blade with a .625" center hole, after making
a centering bushing to mount the blade on, IIRC, the 12 mm
UMK431 output shaft. Couldn't find a pre-made inch-OD/metric-ID
bushing, though you might be luckier.

It has to be kept away from pavement and rocks, and out of
dirt if possible, as the carbide isn't indestructible and
keeping the blade sharp is imperative for both ease and safety.
A light touch, brisk throttle and cutting direction to recoil
away from the work and you  are key.

The problem is that I *have* found some and none are really a
replacement for the original trimmer head that came with the machine
and lasted 9 years.
 
The first replacement virtually exploded on second use and I have
not located all parts yet.
 
The next was advertised for cords of *up to* 3mm but was unable to
cope with them.
 
My current trimmer head *does work*, but after a few minutes in
a real thicket, the cord is seized in its furrow and would not sort,
when I need to extend it anew.
 

Same problem here from time to time. The cure is to perfectly
fill the spool, so no gaps/spaces between turns.

I have a few guesses.
 
An advertised cord size of 3mm means *round* cords, most of the
time, while my own are square and more efficient this way, while
relatively inexpensive.
 
The Honda trimmer head was good for everything, while its diameter
was not above 10cm (most big trimmer heads are 13cm). While the
machine is powerful enough, recommendations may be given for smaller
heads, which resemble the original. In consequence, if I cannot find
a Honda reseller (a bit difficult in our region) I must know which
*other* brands would be possible.
 
Now. Your *experience* may be more interesting and more important
than an actual recommendation. However, if you happen to be in a
comparable situation, you might have a trimmer head in mind …

One option is a flail head. I've tried them and didn't like it,
but your conditions and preferences might be different. Grass
Gator is a brand found in the USA, Europe must have its own
flavors. Flails cut cleaner than cord but react more violently to
obstacles. They're also much more destructive if they get away.

Hope this helps!

bob prohaska