Hi there,
I came across a good source of helical ground anchors and thought I would share it here.
https://www.anchorsystems.co.uk/products/helical-anchors/
If you don't know what a helical ground anchor is then it's a type of anchor that screws into soft earth and provides resistance to pulling out due to the helical 'thread' at one end.
I guess it's an alternative to a straight belay stake, but a portable version that you take with you!
I bought a couple of the smallest size (400mm) along with the wooden winding handle just out of curiosity and I've been quite impressed. They are very portable (a little longer than a school ruler) and not too heavy. You really don't think it's going to work, but in my experience, it actually holds very well.
I even tried putting them into very boggy ground with lots of heather roots, but the screw seems to work it's way down through the roots with no problem - just pushes them out of the way. I guess this is also part of the reason they are so strong for the size - they leave the earth pretty much intact so it retains all the roots etc. that hold it together to resist the pull force.
One nice feature is that when you screw them out again there's very limited 'damage' left to the ground - just a very small hole. I wouldn't use one on someone's lawn, but normally you would never know it had been there.
They are zinc plated steel so I wouldn't recommend leaving them in situ for a long period, but that's a good thing as you can inspect the entire thing prior to using them each time (unlike an in-situ belay stake).
You can buy them directly from Anchor Systems (they send you a proforma invoice) and the pricing is pretty reasonable.
(note if you so a web search you will find the same thing for twice the price at Machine Mart.)
The smallest size - 400mm (up to 400Kg static load) on it's own was approx £10 or £16 with the wooden 'winder' and pouch.
If you're interested I think I would recommend going for the next size up - 600mm long - which holds up to 600Kg static load and costs approx £30.
Even then I would consider always putting in two, to give some resilience in case you just happened to have screwed into a big void in the earth or something.
They do even bigger ones, but of course the longer they are the more risk of hitting a big rock or tree root, so there's a trade-off.
IMPORTANT NOTE: The static load ratings are for a straight pull in compacted earth - i.e. in the axis they are screwed in. If you go too far off-axis, the rating would reduce since when it's loaded the shaft could 'cheese-wire' through the earth, increasing the possibility that the screw could pull out.
If you're wondering when you might use one in climbing then here's one example - I've always been a bit nervous about faffing about at the top of trad crags while building anchors for top-roping etc, especially when there's no fixed protection nearby (trees or belay posts) or where the grass at the top of the crag rises away at a steep angle.
This is a really easy way to put in some protection away from the crag edge and attach a rope while you are building a more robust redundant anchor.
CAVEAT: There are a few variables here around how soft the ground is, what angle you are loading them on, etc. so you need to use your own judgement (as always) in terms of what's suitable. As always, have a backup! I am specifically _not_ recommending using one of these on its own for a belay anchor for top-roping ...even though in the right setting it would probably work fine.
Hope that's useful.
Happy to know if others have tried these and rejected them for some reason.
Dave
Post edited at 13:29
