Firstly let me give credit where credit is due. I think
this idea was originally published in MF, then David Bremner (editor of
MF) provided a little more detail, then Jeremy Harris kindly made me some
of the bits to try it out.
The bit that does the business is thick walled 2” aluminum tubing cut to
a length of about 2”. Two pairs of holes then need to be drilled at right
angles to each other so that when you put 2 tent pegs through them, they
cross in the middle. You need to offset the pairs of holes by the
thickness of the tent peg – in this case 8mm - so that the pegs can pass
each other. It’s quite important that the pegs should not be a sloppy fit
in the holes.
Put the circle of aluminum on the ground curvy side down so that you can
push the pegs in at an angle of 45 degrees. My pegs came with fancy green
nylon bits for tying string to, but I chucked them away as they just took
up unnecessary room. You can push the pegs in quite well by hand or with
your foot, and in very hard ground you can use a hammer or a rock. They
don’t have to go all the way home to be effective, but the further the
better I guess. You can get the pegs at any camping shop – they are heavy
duty 9 inch ones. Most of them seem to be 8mm diameter, so make sure you
drill the holes 8mm.
Once your spikes are in place you can loop your tie-down either under the
top lip of the aluminum ring or as I have done, under the cross-over
point of the two pegs. It takes a huge amount of force to dislodge this
arrangement – why? – well it seems to me that the upward force is resisted
by compression within the top part of the aluminum ring joining the tops
of the two pegs. If the tops can’t move, then neither can the pointy ends
6 or 7 inches under the surface. So it’s like trying to physically
dislodge a 15inch by 6 inch piece of ground. With the spiral ground spike
it’s more like 10 inches by 2 inches, and there is a tendency for the
spike to unwind. By the way to save space in the trike, we buy incredibly
strong windsurfing line – it’s about 4 mm in diameter but has some
ridiculous breaking strain like 1200kg. You need at least 3 m for one
tie-down.
Are there any downsides? – yes – I don’t think the device would be very
good if the string isn’t kept vertical. Ground spikes can be screwed in at
an angle if you wish. And with the rings you’ve got more bits to carry
around ….. but on the other hand – the overall size for a set of 3 is
smaller and probably lighter – and they fit neatly into a short postal
tube. Also the nylon lines would eventually chafe through on the edge of
the rings. It was suggested that shackles could be used, but firstly I
wouldn’t know how to make them and fit them, and it seemed to me that it
could be a weak point. I guess a horse-shoe shaped shackle where the
horizontal bar went under the peg cross-over point would be ideal … but
fussy. I’ll just keep an eye on how the string is doing I think.
This was sent to me via
email: unfortunately I have no information on the original source.
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