Re: [Brushcutter] Need trimmer head for big cords

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

<news:bp@www.zefox.net> wrote in rec.gardens:

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

 

I am cutting bramble, burning nettle (higher than myself) and
everything in between. But remember: No blades.
>

>
That sounds like a job for goats! But, they'd have to be very hungry.
8-)

 
This is just true. Once we had “borrowed” a friend's goat but could
not stand seeing it attached to a chord all day, then moved to
another spot and so on. Our plot of land is not exactly small, but
neither suitable to permanently accommodate goats (at least 2).
 

In the end, I might choose to keep my current head and try round or
smaller cords. There are cords with metal-cores which should last
longer, too. But I have no experience with those.
>

>
Metal-cored string sounds interesting, but also somewhat scary.
If it could be designed to break off only in small pieces that
would be slightly less scary. A link would be enlightening.

 
Okay, I try to assemble some links and images.
 

There's a YouTube video claiming that trimmer cord durability
can be enhanced by soaking the cord in water overnight before use.
It applies mostly to years-old cord that has lost plasticizer in
storage.

 
It is difficult for me to see, how this could be generalized. I try
to imagine the cords and their material. Somehow, plastics chemistry
gets in the way and I cannot get the water in. If the cords lose the
plasticizer (or softener), will they not be more fragile, too? Wet
or not.
 

I agree, it sounds implausible. But, I've learned that some polymers
are penetrated by and their properties altered by water and other
atmospheric consitutents. Photoresist is materially affected by
relative humidity, to the point that humidity control is crucial
to microfabrication operations. It was found by my colleagues and
self that track recording plastic (CR-39) reduced its sensivity
to ionizing radiation when placed in vacuum for tens of hours. IIRC
others later discovered that the presence of oxygen was the key.
Both examples apply to chemical properties, but physical properties
are ultimately chemical in origin.

Here's the link:
https://www.youtube.com/watch?v=irFWBYr_2dA
I haven't been motivated to test the claim simply because line jams
and breakage aren't a large issue in my environment.

It sounds to me like a two-stage approach might be necessary.
One pass with loppers or a saw to remove hard perennial growth
larger than a few millimeters, then a second pass with heavy string
to cut the soft stuff. The first pass will be hard work, but needed
only once if you follow up (often!).

 
Depends on the exact spot. I have begun to clean away the bramble
inside a ruin, where it grows out of the debris. But most of the
time, I use the brushcutter after passing the rotary shredder, to
finish the borders at a length of about 100m, around our heaps of
firewood and similar. We also have a small parcel, densely populated
by diverse trees, a “spinney” (UK) sais my dictionary.  Here, I do
*not* want to intervene too often. It is however not a forest and
the scrub threatens to become impenetrable, sometimes (not that *I*
cared much, but I am not alone).
 
All the remaining tasks are no problem for the brushcutter.
>

 
By chance I found this video on trimmer heads and cord:
https://www.youtube.com/watch?v=nIr2t-bIj4k
It's US-centric, so it may not help. It does repeat
the claim that old cord gets brittle, but no mention
of soaking it in water.

Hope this helps, a photo or two would be very instructive.

 

I will see what I can do.
 

Not a matter of huge importance at this stage, but you've piqued
my curiosity. Is fire risk a worry for you?

bob prohaska