Did the stones come with an axle in each? If so, is the axle "bent " on one side, so that you can fix a rope, or strap to it, and the other end to your footpedal( treadle)? If that is the case, you can make your frame pretty much anyway that you find comfortable( or uncomfortable if you are a masochist!) :rotf:
Take a look at any shaving horse, or a bench made by a saddle or harness maker with a leather vise in it, and you have the basic idea for the frame to hold the grinding wheels. The originals were made for rather small( I am being very kind, here) people, so don't take their dimensions too seriously if you value your lower back! :shocked2: :blah: :rotf: YOu want the seat to be high enough so that your leg, at the knee does not bend down to a 90 degree angle in order for you to sit on the seat, and straddle the "horse" frame. You want enough clearance so that your foot can reach the pedal( or treadle) without stretching, or bending the foot back. Make your frame fit YOU, not some midget that might have used an antique version 150 years ago. The width of the frame is controlled by the width of the wheel, basically. They are usually angled to the seat, to give wider support for your backside! The legs are usually set into the frame at an angle, again, to give more stability. The only question of authenticity, if you are building a replica, is what kind of gear are you going to use to carry the axles on each side of the frame. If you go to blacksmithing conclaves, or antique fairs, that is the part of the grindstone frame to which you want to pay attention. If the stones have not been used in years, they need to be cleaned, and it helps to soak them with water before trying to use them much. Otherwise, they may have dried to much and can develop cracks, or chip out. Don't expect them to be perfectly round when you finally get them turning in your frame. They rarely were back in the time, either. Everything was held free-hand to the grindstone, so the amount of pressure put against the stone at any point in the arc, based on the stroke of the foot pedal(s) will often created a worn section and makes the wheel get out of round. YOu can use a grindstone wheel dresser, if you build a frame to support it, to take off the high spots, and return the wheel to round, But, such frames are rarely seen on those old, original wheels.
On modern grinders, you see a "J" shaped shelf made of steel that is adjustable for length( in and out) and for angle to the stone, and you can buy a wheel dresser tool to dress the wheel round again, after mounting it on the axle. The Wheel dresser hooks over the edge of the steel shelf in front, and you rock the tool into the stone at high speed to remove enough grit from the high spots to make it round again.
Depending on their condition, you might want to look around your area for cemetery monument carvers, because they usually have the equipment to dress large grinding wheels. They may be able to round those old wheels for you far cheaper than if you have to try to acquire the tooling to do it yourself. There are other steel plants, that operate huge grinders to cut steel plates to exacting dimensions. They may also be able to do this work for you.
Nothing ventured, nothing gained.
