Office of Steam Forum for Model & Toy Steam Gas & Hot Air Engines

The Regular Stuff: Chat, Buy, Sell, Off Topic, etc. => General Discussion - Scale Model Gas Engines - Hit & Miss - Throttle Governed - Non-Compression – etc => Topic started by: Adirondack Jack on September 16, 2020, 01:22:10 am

Title: Water pump project update
Post by: Adirondack Jack on September 16, 2020, 01:22:10 am
The little piston water pump is getting close to completion.

So far, I’ve got a cylinder. and piston, a bottom end for the piston, a connecting rod with a bushed small end and ball bearing big end, a twin ball bearing crank pulley, a big and a small reduction pulleys, check valves, and the cylinder head done.
I’m two pillow block bearings and the framing structure away from having it done.

Details:  3/8 bore, 2 inch stroke. Connecting rod 3.5 inches long. Estimated run speed of 50-60 strokes per minute, will yield 5-6 ounces per minute.

The bore and piston are telescoping brass.  The piston seal is simply a cork rammed tightly into a well beveled and polished piston top end, the protruding cork sanded  with 500 grit to a nice fat, very smooth “pancake” shape that fits the bore with little resistance but little if any leakage when wet. The piston, cylinder wall, and piston seal are  lapped and treated with beeswax. In simple hand powered tests it doesn’t leak, and pumps both air and water happily.

Onward to making the pillow blocks for the high speed pulley shaft. Then a framework, and a couple of belts to sew, and it’ll be done.