I cam to the conclusion with my mine that the nylon feeders just don't work
too well period (I am pretty impatient with this sort of thing though, if it
should work then it darn well better!). I eventually gave up and purchased
one of those 'gator' attachments that have 3 blades.

They Gator heads work well but do have some disadvantages. If you catch
something hard with them they can break, I caught a rock once and broke one
of the metal blades (it's only made of a cheap alloy as far as I could
tell). If you break one of the 3 blades it will throw the trimmer so
helplessly out of balance that you have to fit a new blade immediately, if
the other 2 are signigicantly worn then the new one you fit will also throw
the timmer out of balance (it'll vibrate like crazy in your hand). So you
end up with a sack full of half worn out blades that you end up rummaging
through unti you find 3 that are as identical as possible. New blades
(espiecialy the alloy ones) are a little spendy. I exclusively use the
plastic (nylon) ones now they suffer from the same problem if you break one
and you just have to be very careful if trimming grass around a brick wall
or something.

In the back of my memory the head that fits the alloy blades have different
size rivits that those with the nylon blades and they are not
interchangeable, but check that at the store as I could be wrong.

Good luck. Mark