Not so much trail building as trail maintenance; here is a weed wacker accessory that works very well;
My initial problem with the OEM self feed string trimmer head was that the string sometimes did not feed. I found that this was mostly due to when used for a long time the head heats up and the string tends to weld itself together. The other problem was that tall grass and vines wrapped around and got into the gap of the rotating head- they took a long time to clean out and made a lot of friction, which made the head hotter (I melted the plastic on one head!) and sometimes smoked.
My solution was to give up on the self feed altogether and go to a head which can used very heavy string (cuts better and lasts longer). A bonus was that the rotating section was properly designed so that grass cannot wrap into the housing.
The Trimmer Plus AS720, fits Ryobi Expand-It and similar;
COMPATIBILITY: Fits Attachment capable Units from Troy-Belt, Remington, Craftsman, yard machines, yardman, Snapper, Boles, Murray, Ryobi, Green works, Cobalt and most other major brands. Inner coupler tube Diameter: 1. 65-Inches. Drive Shaft connector: Square shape, 1/5”, Female.
Amazon.com : TrimmerPlus AS720 34-Inch Extended Reach Aluminum Fixed Line Head for Attachment Capable String Trimmers, Polesaws, and Powerheads Boom : Garden & Outdoor
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I have used this heavily for 2 years, I think It is starting to make some noise (hard to tell with motor going). I can use a second one, so I will open up the first to see what is going on. 2 years with the abuse I give it is not bad. Cost about $70.
As far as trimmer line goes, I have had good luck with Huskvarna 0.1" Titanium line.
Amazon.com : Husqvarna string trimmer line .105-Inch 115ft spool Titanium Force High efficiency Long life Faster acceleration : Multitools : Garden & Outdoor
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