Building Homemade Horse Cart?
My dad is a master weldsman as well as a master carpenter (so I have two options as far as material), has built hundreds of racecars and race go-karts, as well as my personal goat cart, and also is just super creative in the head, and I'm hoping he can help me build a cart to start working with. My mare is 16hh, I'm looking at building a 2 wheel, single horse cart, with a seat that can hopefully fit two people (maybe squeeze in a small third on occasion, or sit three people comfortably if possible) and be road safe. She has been cart broken, just with someone elses cart.
My brother is handicapped and I have two pairs of wheelchair wheels, that are SUPER durable and light and can hold up to 500+lbs (not that I'd make them do that all the time). Its definitely going to be a pleasure cart, NOT a show cart, maybe going on trail rides (cart accessible trails) and parades, but mostly riding roads, 90% of those roads being dirt roads. Not going to be fancy, but needs to be safe and considerably light, and unsure on requirements on most carts, but it will need rigging for breeching (I may have said that incorrectly) as we will occasionally be going down hills, and I had issues with harnesses coming slap off without breeching when I worked cart goats, and I just won't test that happening again with a horse.
As far as seating goes, like I said, needs to at least sit two people comfortably. My brother will occasionally be riding, NOT alone, so it will need to be accessible enough to lift 70lbs onto it by yourself without having much of a step (the highest we typically can manage is lifting our leg into the floorboard of a medium pickup, from the ground, but I mean if thats just not reasonable we can manage). We will be figuring out seatbelt options for my brother as well, but don't need help with those. Seat will need a back.
As far as lighting, I need advice on what would be best. We will be riding rural/urban roads, nothing too high traffic, but still public roadways, so maybe flashing lights? My dad can figure out light rigging, its just WHAT lights would be needed. Or are reflective lights with slow moving vehicle signs sufficient?
The best thing I'm looking for are building blueprints or plans. But I know those aren't always available. Any advice anyone can give is greatly appreciated.