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@GBBUDD said yes to all of that, set a lot by myself and some with help. I used two endless straps (can hook and unhook them quickly) so I could use them as big loops or run them through themselves so they would pull tight on the rock. Another trick when setting rock with straps by yourself....tie a rope to use as a a tag line to one of the straps so you can sit 8n the excavator and turn the rocks the direction you want them. Last thing I will add don’t reach way out to set any large rocks with the excavator turned cross ways to its tracks, unless you are experienced running one as the machine can and will tip. There are tricks to do it with out the machine tipping over, but it takes a certain comfort level and experience knowing your equipments limitation. Ideally, the excavator has a blade on it that you can keep in front of you and use as a stabilizer when reaching way out over it to set large boulders. I had to sit side ways to the pond occasionally(space constraints), and had to use a couple tricks I know to set it out the machines reach limit.
You can do as Gbbudd said and set the big rocks on Little Rock’s to get the straps out or have a 3rd strap and you can hook it up to an edge to lift the rock slightly then pull the other straps out. Also agree with him in use non woven fabric even double or triple it up under the big rocks. Where my leak was I just put one layer of the 8oz fabric over the liner and even a little Rock (150lb)cut through it, which I didn’t think would happen.
I set all the huge boulders with straps and set the smaller ones (but bigger than I can lift or man handle) with the thumb, depending on where I wantEd it to go. Just make sure to take your time to get a good grip on the rock as they will squirt out of thumb Occasionally. It didn’t happen to me while building the pond, but it happens sometimes while I am at work ( I build stone revetments and living shorelines on the waterfront as part of my business).