Has anyone ever installed these? I'm thinking of using ground screws to install the mounting rack for a solar system. I know my post hole digger won't work because it doesn't have any down force, and they're 73" long so my post hole digger isn't tall enough. The people selling them say you can use a skid steer with an auger head, but the videos I see on youtube use more specialized equipment on either mini excavators or mini skid steers.
Installing ground screws
- Thread starter BeezFun
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blackxrunner
New member
i imagine soil type could also play a big part in what you would need to drive them in especially the downforce requirement. Light soils I imagine once it gets going it drives itself. I think there are actually portable hand held(maybe 2 man) type units to drive them in as well. I can't imagine being able to generate much down force with those.
ponytug
Super Member
I used six to hold down a tarp covered run in ShelterLogic shelter for horses and cows. I have heavy soil in that area, and I can tell you they would not have gone in during dry weather without a skid steer hydraulically driving them in. With damp soil, and a 4' steel handle, I drove mine (4-5" in diameter) about 30" down. They have held through 70+mph gusts, but that was six grounds holding a Quonset hut type shelter down. If it blows away, it's a $1,000 loss. Your solar will be a much more expensive loss if it blows away.
All the ones that I have seen driven with a skid steer had a special driver socket on the end. I have seen excavators drive big ones (36") 20' deep for house foundations, but that took serious horsepower.
If I it were me, and I was thinking of installing bigger and/or deeper (which you are) ground screws, or in hard soil, I would reconsider and go with concrete. So, yes, I would rent a skid steer for the day and get the holes done and move on.
Sorry. Probably not what you wanted to hear.
Congratulations on the solar. How many kW are you putting in?
All the best,
Peter
All the ones that I have seen driven with a skid steer had a special driver socket on the end. I have seen excavators drive big ones (36") 20' deep for house foundations, but that took serious horsepower.
If I it were me, and I was thinking of installing bigger and/or deeper (which you are) ground screws, or in hard soil, I would reconsider and go with concrete. So, yes, I would rent a skid steer for the day and get the holes done and move on.
Sorry. Probably not what you wanted to hear.
Congratulations on the solar. How many kW are you putting in?
All the best,
Peter
Rustyiron
Super Member
I believe that there used widely in Europe.
The internet has your answer.
The internet has your answer.
We have 5 shelter logic buildings, pretty good value for the money. I've had better luck with the duckbill anchors about 4' deep. We have a lot of rocks in our soil, putting in those helical anchors can be almost impossible.
I've put in a bunch of concrete posts for buildings here, the problem is our soil is really rocky, we live on a glacial till. Even with a skid steer there are spots I couldn't get down to frost depth unless I break out the rocks by hand. This is the kind of ground screw I'm considering, I think it has a good chance of making it through the rocks we have, which are round and about grapefruit to melon size.
7.6kW, I can feed that back through the subpanel in the barn without running much wire or changing anything. If this all works out, I'll likely put in a line tap back at the meter and trench a line from the barn to the meter, then I can put in about 16kW, which is what the utility here will allow based on our historic usage.
ponytug
Super Member
For glacial till, those ground screws look awesome. I grew up with soil like that. Mine have much larger flights and would be a royal pain. Can you use your tractor to drive them?
All the best, Peter
My post hole digger is useless because of the rocks, no chance of putting these things in. I didn't realize when I bought the post hole digger that without any down force it wouldn't work here, I wasted my money buying the thing. The company says one thing that's important is not to just spin the anchor, it has to progress like a screw into wood. Otherwise it just churns the soil up and it doesn't develop the proper pullout resistance. I'm kind of figuring the worst that can happen is I won't be able to get a few of them to go in, so I'll dig a hole with the auger, put a bolt through the screw so it won't pull out, then pour concrete around it.
ponytug
Super Member
I feel for your pain on the lack of downforce. Anyway to add it to your tractor?
I suspect that you will need it with your soil and that auger.
All the best, Peter
The ground screw is 6' long so it won't fit under the head anyway. I bought a post pounder, much less work than digging a hole and then filling it up again, so I don't really have any use for a post hole digger anymore. If I ever needed to dig a hole I'd rent a skid steer or a mini excavator.
3Ts
Elite Member
If you use a ground anchor, be sure the rod is in-line with the cable once it is installed that is attached to it. I've seen where the anchors are driven straight down and the tie point is at 45* angle - it doesn't hold very well.