I built a dolly for my Grandby, and I thought I’d give some information about my experience. I used 6x2 wheels of very good quality rated at 1200 lbs each, two fixed, two swivel. I did my framing differently and have a plywood deck, but to each his own on that. I built a quality dolly, as I’m sure you will. What I wanted to convey is that, even with good quality casters, the camper does not just roll around easily even on perfectly smooth concrete. Also, the swivel casters don’t easily swivel under that load. My garage floor slab has a slight slope of 4 inches in 24 feet, which makes it even harder. Moving the camper by myself is very difficult and involves wrenching the casters around when I want to change direction. Even with two people it’s not easy.
I just want you to have realistic expectations for a dolly like that. Bigger, more narrow casters might make it work better.
Also, disassembling the dolly for storage seems like a lot of hassle. I stand mine up against the wall and tie it in place. Takes up less than 4 square feet.
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