Update  July, 2008

This past year has been busy with two other businesses to run.  This has become a sideline hobby, but still a lot of plans and engines and cams managed to go out.  A lot of interested people ask for specifications, btus and power outputs.  I have some of that but I am not a scientist, just a pragmatist.

I have made very little progress on the Typhoon.  Made the Virtual cylider head and got the piston wiper extruded.  So little left to do before a test can be made.

Background

In 1993 I attended an electric car show in Boston MA. It was a big show and included every possible alternative energy, gizmo, motor, etc. you can imagine. That same year I joined the Stanley Steamer Historical Society and attended one of their meets in New Hampshire. Riding in an open top Steam car around the White Mountains was a thrill. I have to thank the Stanley Museum for making available a tremendous wealth of information and data on all sorts of Steam Cars. Thank you for preserving a tremendous resource.

This got my juices flowing and in 1995 my first prototype was finished. It was a two cylinder double acting steam engine cast and machined for about $4000. The valving is integral with the center crankshaft bearing. This engine has five moving parts. The clearances are too large and the ports too long. (I never tried this engine with anything more than 50 PSI.) Learning from mistakes is a powerful thing.

In 1997 I converted a 4-HP lawnmower engine to a single acting single cylinder engine using a single rotary valve mounted on the head that is run from the crankshaft by a timing belt. To my amazement it worked on air. It was a little rough and required a large flywheel. I never could get it to work on steam. Later on I discovered that the port openings were just too small and the cutoff was too short. This is good for high pressure air though. So in doing this I never really discovered much about steam and rotary valves.

But with some proof of the rotary valve I decided a double acting cylinder would double the power output at least and smooth out the cycle. While involving a longer engine because of the need for a crosshead, I set about to solve as many issues as I could if I was going to design and build from scratch.

In early 2002 I scrapped every idea. I re-read every book on steam engines. A few sentences started jumping out at me. The essence was this.

1. Using no more than 450-degree steam, the lubricating oil can be circulated with the feed water with out risk of burning, scaling or priming.

2. Compression is a problem when trying to get the highest expansion rate.

3. A simple engine can be run efficiently and with a low water rate with a cutoff of 15 - 20%.

4. A multiplicity of cylinders is only necessary when using superheated steam.

5. A Monotube boiler can be made very compact if no reserve capacity is required, and the engine is run at a constant and optimal speed.

6. The engine and boiler can be unitized.

7. Clearance space and port lengths should be kept to an absolute minimum.

8. The cooler exhaust should be insulated from the hot steam inlet side.

In March of 2002 I started on a double acting single cylinder engine, with enclosed crankcase, two rotary valves. In July it was finished and after tinkering with port sizes and timing it ran OK. It was quite a moment when after almost giving up for the day, I reset things one more time, turned up the pressure and nothing - again. I thought. Then I dont know what caught my eye but the flywheel was spinning about 500 rpm. The little 1" piston motor self started, and spun up with out a sound. I must have spent another hour just playing with it before going home. I even let my wife hear it over the phone. Not much to hear without the exhaust off. She loves me.

The Lynx Engine met all of the design requirements stated above and held enough promise to make a full size model capable of powering a car, boat or home. So with my 6 tall engine in hand I set off to machine shops around Ann Arbor. Impressively the little engine would self-start for the machinist with a blast of compressed air and run at 500 rpm. The engine only has about 6 moving parts, not counting auxiliaries. In August the parts were being machined for a 2.5 Bore and 2.5 stroke engine. The engine without auxiliaries stands about 13 tall and is 6 deep.

So, now an update.

The rotary valve engine works fine but it is more difficult to build than I had hoped. The prototype engine has cost over $5000. The skeptics who said rotary valves dont work were half right. The wisdom of these gurus of steam is that rotary valves either sieze or they leak. This is correct, but if lower temperatures and pressures are used the problem is less severe than if steam at 800 F and 1000 psi is used.

Using lower pressure steam and zero tolerance tapered Teflon valves solved the leakage/seizure problem. While listening to the wisdom of those in the field of steam I learned so much. So following their advice I determined to try some other designs.

I must thank the kind people at the Steam Automobile Club of America for inviting me as a guest speaker this fall. I learned far more from them than they learned from me. I hope my young optimistic enthusiasm rubbed off on them a little. They also loaded me up with about 20 Lbs of Doble books and his complete engineering notes. I am very grateful for all their encouragement and help.

It is correct to say that the best designs will utilize high pressure steam and multiple expansion. This gives low water rates, smaller boilers and safe operation. I am just not comfortable with these high pressures and temperatures and the cost to build a triple expansion engine is beyond my means. Also when talking about small 1-5 hp engines it becomes a difficult challenge to assemble all the components in that size.

The result of my experiments and discussions with experts is a lot of practical knowledge with different valves, uni-flow vs. counterflow, diaphram pistons, bash valves and their timing challenges, and more ways to fire monotube boilers.

While I like the rotary valves for their timing flexibility, I now prefer the tried and true formula of uni-flow simple expansion, with separate inlet and auxillary exhaust. This combination results in a high expansion, low compression engine.

I have reached the conclusion that the biggest market for 1-5 hp steam engines are those people interested in the hobby, producing standby power with solid fuels, and for those interested in quiet co-generative power.

All this adds up to low pressure - low temperature. At this size engine fuel economy isnt the over-riding concern, and the complexity of a 1000psi 800 F steam system just isnt practical.

The perfect low cost solution is the conversion of a small horizontal lawnmower type IC engine to steam. The cam and push rods are already there for steam piston valves, or just using the poppet valves in a single acting design.

The only way to do the boilers right is to have them made by an ASME certified firm. Keeping these boilers within the definition of "Miniature Boiler" is another reason for going low pressure steam. Two models are being made for Lynx - a downdraught and a bottom fired.

If you want high pressure and high temperature steam you are on your own these days. The laws are strict and the frequency and cost of inspections by certified ASME inspectors will overwhelm you.

So check out these pages to see whats happening and the products we make available.