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19th Century Steam Launch engine Plant.

Here are additional pics on the little vertical steam engine. From the bottom of the base to the top of the cylinder the engine measures 18" tall. I would say it weighs fifty five pounds or so.


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More additional detail pics. I love the water plunger pump setup on this engine.


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And a few more random pics of various angles and components. Anyone have a guess as to which steam engine manufacturer used a Bear for their Trademark ?


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And the last. Gil Garceau posted the page showing the governors and who sold the castings for them. Mine is brass in 1/4" pipe thread. This pic is under Harry's Mathew's "Smokstak" which is another thread on this engine but not in the same depth as this one :)

The governor needs a lot of TLC but it will be a fun project to restore. I think it is too small for this engine. A more substantially built governor would look better.


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Thanks for posting that picture of the 'gal with the outboard motor. She gives new meaning to the terms: "Recoil Starter" and "Pull the ripcord". In my own lifetime, plenty of small engines and light power equipment were sold with simple rope starting. It was more common than not in the 50's, and open and unguarded sheet-metal "cups" with rope notches spinning on small engines were commonplace.

The pictures of the engine are quite interesting. Seeing the feedwater pump driven off the crosshead puts things to rights, as it seemed like otherwise, someone in the boat would be kept busy hand-pumping the feedwater pump. The feedwater pump looks like an addition to the engine, something the person converting the engine for marine use built and added on.

I am still a bit puzzled as to why a marine steam engine would have a governor. A small engine and boiler as these are would be fitted to a very small steam launch. Such a launch would (or at least should have been) steamed in quiet waters and very likely on fresh water (assuming the engine ran non-condensing and drew makeup feed from overboard). What this thinking builds the foundation for is that the launch would be extremely unlikely to get into heavy enough seas where the screw (propellor) would come out of the water and cause the engine to violently race. That would be about the only reason to have a governor on a marine steam engine. In actuality, marine steam engines never had any sort of governors. The engineer on watch had to work the throttle when the ship was in heavy seas, slamming it closed before the engine could race to destruction. In heavy seas or worse, the skipper would head the ship into the waves. The engine would be working hard to keep the ship headed into the waves, with the ship not making much headway. In really heavy seas, the ship might well wind up with the screw out of the water for short periods of time. Some of the big reciprocating marine engines had a butterfly valve in the steam line ahead of the actual engine throttle. In heavy seas, the engineer could slam that butterfly valve shut a lot quicker than he could close the throttle- which might have been open a good amount to make any kind of turns with the ship running bow-on into the waves.

Why this little engine has got a governor is anyone's guess. The most likely answer is simply that the person who built the steam plant liked the looks of a spinning governor. A spinning governor atop a steam engine does tend to attract attention and looks like the "finishing touch", even to people who know nothing of steam engines.
An old book I have called "Erecting Work" by one Hubert Collins, written around 1900 speaks about this. Collins describes the sequence of work in erecting a large cross compound Corliss engine, mainly details on how to move and rig the various parts. Collins offers a suggestion to erecting men: something to the effect that if people (aka "sidewalk superintendents") who know nothing of engine work are saying the work is going too slowly, or the man in charge does not know what he is doing, as soon as possible, set the governor in place.

A spinning governor does capture people's eyes and intrigues nearly everyone. Possibly the man who built this little steam plant was a stationary engineer in a steam plant, and having a governor made him feel like he had a "real steam plant" in his boat. I think it unlikely that swings in boiler pressure from the porcupine boiler would have created a need for a governor to keep the engine speed steady. In today's world, we'd call the governor: "eye candy", or in my terms: "the cherry on the sundae". It's a nice little governor in its own right, whether it belongs on a marine steam plant or not.
Thanks for posting about your engine and boiler.
I seem to recall seeing similar looking engines in various old magazines I have looked at over the years but I can’t remember where I saw them and can’t identify the bear logo .
I did a little searching in some places I had looked before to see if I could find anything .
Here are a couple of links to pages I noticed while scrolling through a book I found that you may find interesting .

Steam yachts and launches, their machinery and manegement ... - Full View | HathiTrust Digital Library | HathiTrust Digital Library

Steam yachts and launches, their machinery and manegement ... - Full View | HathiTrust Digital Library | HathiTrust Digital Library

Book Link.
Catalog Record: Steam yachts and launches, their machinery... | Hathi Trust Digital Library

Two more good books NOT on the Internet are

The Steam Launch by Richard Mitchell
Steam Boats and Modern Steam Launches by Bill Durham

I have a Dick Mitchell signed copy of the former. We all regretted the passing of Dick a few years back. The Durham book is a more "modern interpretation" written at the 1960s re-emergence of steam boating with engines and boilers made from whatever handy (air compressor conversions, porkies, once throughs)

Both are available from Amazon or abe books.

I think of the two I enjoy the Bill Durham book better.

OBTW, a fiberglass launch hull you might consider for this engine/boiler is the 19' "Thayer Launch" which were available recently - and occasionally pop up in the hobbyist journals. May be still available. Google "Thayer Co" and you should come to its source. Check out Steamboat Register

Edit: Thayer Co. seems to be Grand Mesa Boatworks in Colorado and the principle James "Jim" Thayer. A GJ Sentinal Write up on Jim exists online Landlocked boat builder renowned by sea travelers | GJSentinel.com - and also his 2011 obituary .James Thayer Obituary - Grand Junction, CO | The Daily Sentinel

Sad news for fans of boat builders

Joe in NH
Jim! Great links! Thank you! Also Joe..your right. Bill Durham's book is a wonderful read. I have a hardbound copy of all the magazine issues which I have read cover to cover many times over. Thanks for these links and suggestion guys. Very much appreciated. Jim..that link you posted showing Kane's engine almost looks like mine..more research :)

I'm still working on getting the "porcupine" exposed. Lots of heat needed to avoid destroying these early pipe fittings. I have managed to burn myself frequently lately. So many tentacles of pipes and fittings I forget which ones are hot!

More later after some progress. Thanks Jim and Joe..appreciate your research :)


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A spinning governor does capture people's eyes and intrigues nearly everyone. Possibly the man who built this little steam plant was a stationary engineer in a steam plant, and having a governor made him feel like he had a "real steam plant" in his boat. I think it unlikely that swings in boiler pressure from the porcupine boiler would have created a need for a governor to keep the engine speed steady. In today's world, we'd call the governor: "eye candy", or in my terms: "the cherry on the sundae". It's a nice little governor in its own right, whether it belongs on a marine steam plant or not.

You are quite right about the eye candy appeal of a governor. In our mill engine museum I probably answer more questions and spend longer time on describing the action of governors than anything else. We have everything from early Watt style governors up to the fully enclosed side shaft governor on a Uniflow. If we have visitors with an engineering background you can use the development of the governors seen on our engines to describe the growing understanding of control theory, from why early engines hunted through to PID control. A lot of people are quite surprised that many 'old' engines have variable inlet valve timing - something they associate with very modern car engines. Necessity drives development and for textile mill engines, particularly for cotton spinning, it was necessary to hold the engine speed constant within a few percent regardless of the load which was constantly changing.

We do have a launch engine in the museum which is fitted with not one but two governors. It also has two different sets of valve gear, one of which is reversing. This Sissons engine, although based on their popular launch engine design was actually used as a teaching engine in a laboratory and was specially built by Sissons for that purpose. It is fitted out with every possible extra and full instrumentation so that it can be run in many different modes. So for example it can be run as a compound engine, or as two entirely separate single cylinder engines. The crankshaft has a centre coupling, which when removed allows the two halves of the engine to run at different speeds (two governors!) or even in different directions. Towards the end of one of our steam days we sometimes set the engine up so that it is running in this way - i.e. different speeds and directions. It is surprising that very few visitors notice that the engine is doing anything unusual in this form.

If you would like to see this engine go to http://www.nmes.org/ under 'other engines'.

I am glad to read that your steam plant is coming along in your capable hands. A word of advice about working around hot parts and similar:

I wear TIG welding gloves fairly routinely when I am working around hot parts. While these do not provide the insulation of heavier welding gloves, they are thin enough to give some dexterity, but also provide a bit of a barrier between your hands and hot metal. Another think I do is carry a piece of soapstone in my shirt pocket or in close reach. If I have multiple parts that are hot, I sometimes mark them with the soapstone. With a few things going on at once, a person can get ahead of themselves and wind up burned or worse.

A funny little story on this vein comes to mind. Back in the 70's in Marquette, Michigan, there was a fellow who had a small dealership for FWD (four wheel drive) trucks. FWS trucks are quite high-riding and are heavy trucks sold mainly for highway snowplow service. The fellow who had the dealership was a one man shop. He handled sales and service. He was said to be a smart man and good mechanic, but absent minded as could be. In one instance, he was working inside the cab of one of the FWD trucks and for whatever reason, had to exit the cab in a hurry. Maybe a buddy poked his head in the shop door, maybe the phone rang (era before voice mail). Either way, this fellow stepped out of the cab of the FWD in a hurry, forgot the height of the cab off the floor and took a bad fall. It put him in the hospital.

On another occasion, this same fellow was working on a latch or part for a spreader box (used to spread sand on the roads off the back of the trucks). He had an oxyacetylene torch with a brazing tip, a ball pein hammer, and was heating and forging the part to shape in a bench vise. He'd take the part in a pair of pliers and try it where it needed to go, decide it needed more tweaking and put it back in the vise for another round of heating and hammering. The fellow was wearing baggy, oily coveralls (boiler suit to our Brethren in England & Scotland), and kept putting the ball pein hammer in the back pocket. At some point, the fellow got his wires crossed and put the lit brazing torch in his back pocket instead of the ball pein hammer. His oil coveralls promptly caught fire. Another person got him on the floor and rolled him into a tarp, putting out the fire. Another trip to the hospital and some skin grafts followed.

An old trick that people working on steam plants with stubborn fittings, stubborn nuts and studbolts and similar used was a combination of heat and beeswax. After heating a threaded part that is frozen in place, they would touch a block of beeswax to the exposed threads and let it melt in. For whatever reason, the beeswax tended to "wick" into the threads as things cooled and often "broke" the connection so it could be taken apart.

Much has been written on penetrating oils, with a wide consensus holding that a 50-50 mix of automatic transmission fluid and acetone works better than any commercially available penetrating oils. While this may well be true, a mixture like that, used around a torch to get other connections broke loose, is obviously a recipe for a blaze or worse. The beeswax is likely a safer bet.

Another thing I do around hot work is to wear a long sleeved cotton shirt or welding jacket. It is all too easy to brush against something you've heated with your torch and wind up with a burn on your arm. I did just that a few weeks back. I was doing a "little" forge work, and was working at my anvil and forge. Since it was a hot and muggy day, I was in a tee shirt. Of course, once I had a good fire going in the forge hearth and it was coked nicely, I started remembering other little jobs. One thing led to another and I burnt the better part of a bucket of smithing coal. At some point, I swung around to do something or other and my right elbow brushed against the tip of the horn of my anvil- a 200 lb anvil at that. It was HOT. I got a nice burn on my arm, imprint of the anvil horn, flesh burned down and in. Not the first time I've been burned like that. I kept working, fire in the forge and strike while the iron is hot. I came into my house when I was done, and put some ice on the burn, which was hurting. After that, I broke a "spike" of an aloe plant and put the goo on the burn. I treated the burn with the aloe plant goo, and the result is it healed quickly and does not look like much, if any scarring will result. We keep a few aloe plants around the house for treating burns and sunburn. I am great believer in aloe plants. One time, I was doing some brazing under a truck and some globs of braze metal went past the cuff of my glove and down the sleeve of my coverall, burning my flannel shirt. I knew if I stopped to deal with the burn, my wife would make me stop work for the day. I threw some snow down my sleeve and kept working. That evening, the arm was a mess, a deep burn right down the forearm looking like it would be a job for the hospital. We called my buddy, who is quite wise in matters ranging from shopwork to healing. He brought over the aloe plant and bandages. He cleaned the burns, dressed them with aloe goo and bandaged me up. The result is I healed quickly and no scars.

So, word to the wise: wear long sleeves, even if it is hot outside, wear TIG gloves, keep an Aloe plant handy, and mark your hot work with soapstone to keep track of what you are doing and where you are at with it.
I finally was able to remove the top cap of the Porcupine. The nest of tubes measures approximately 16" x 16" with a 4.250 central thick walled tube in the center. At this point I cannot tell if the central tube is cast iron or steel.It feels like cast iron but when I reach up through the bottom and feel the "bottom cap"...it feels almost like it is welded. It is not capped off like the top.


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The actual "quills" or tubes appear to be 3/4" pipe nipples x 6" long..at least the two top row of tubes. These seem to be capped off with 3/4" pipe caps. Starting with the third row of tubes,the heads are swedged or formed in some way to presumably allow some sort of socket tightening.

Strange little beast.It would seem to require a constant water feed with such a low steam capacity. This probably explains the feed water pump on the engine which was probably regulated for a constant feed. I would imagine some sort of clutch set up must have been used so the engine rotation could be continuous.

I need to remove the boiler from the base to be able to remove the wrapper. This comes next.

One of the pics show the steam outlet pipe which goes down through the hot gases and exits through the wrapper. As you can see I broke that nipple.

Seems to be a very inefficient little boiler. It is nicely made with the cast iron top cover. Oh! As you can see the top row of tubes are neatly angled to fit the contour of the cast top cap. A nice touch.

The cap on top of the central tube ( main steam drum? ) has no "tell tale" of threads. The little piece broken out from the edge of the tube appears to be a chip of sorts.


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I got curious about the "Porcupine Boiler" design. What I found out is that many years ago, the Hazleton Boiler Works (Hazleton, PA) built what they called a "porcupine boiler". This was much larger than what you have in your little marine steam plant. The Hazleton boilers used "horseshoe" shaped U bends of tubing rather than single quills off the center drum. These horseshoe bends of tubing were arranged so they laid at an angle to the horizontal (or off square to the centerline of the vertical drum). The result was a great number of these horseshoe bends were stacked around the center drum with an appearance somewhat like a pinecone.

Your boiler has simple radial quills. I wonder what the circulation in them was actually like. The quills with the square swedged ends may offer a clue. My belief is that the square-swedged ends on the quills may well be made by forge welding. Possibly, an inner quill, made of smaller diameter pipe with some perforations drilled out towards the swedged end is inside each of those quills. This inner pipe is forge welded to a piece of bar stock to plug its outer end. The bar stock was then forged square, and the larger diameter "outer" quill was slid over it. The larger outer quill pipe may then have been forged to a snug fit on the square end of the inner quill, and forge welded. The inner quills may have incorporated elbows on the inner ends, looking downwards. These would capture the rising flow of water in the vertical barrel (due to the heating), and send it out to the ends of each quill pipe. There, having absorbed heat from the boiler fire, the water would travel inwards to the center drum (via the annular space beween the inner and outer quill pipes), and rise up to the steam releasing space.

Otherwise, it would seem the radial quills are "dead end streets" for the water in the boiler and circulation would be a very erratic proposition. With the quills simply being plugged (or capped) pipe nipples with no pitch to them, the water in them would boil, flash to steam, and blast the water between the steam bubble thus formed and the center drum. There might have been a fairly noisy and violent sort of action as steam bubbles formed in the quills, blasted their way to the center drum to rise to the releasing space at the top of the drum. Water would then rush into the quill and likely flash to steam as the quill- having blasted out the steam bubble- would be essentially empty for an instant in time.

My concern with this boiler is scaling on the inside of the quills. Without a definite or positive circulation path, the danger would be localized overheating of the quills (as happens when the steam bubbles are expanding out). Scaling within the tubes would be a likely outcome.

The fiberoptic video "snakes" with minicams are quite common and are used by plumbers to look for pipe blockages, or to inspect insides of piping. Home Depot and similar stores carry these fiberoptic snakes (I believe Rigid, the pipe tool company, markets such a snake). Using a video snake to get into the center drum of the porcupine boiler and working the snake into some of the quills is something I'd suggest. If you can get a piece of 1/16" or 3/32" diameter TIG or brazing rod worked into the center drum with an "L" bend on the end to direct the fiberoptic snake, you may be able to inspect inside the quills. Between the internal inspection with the fiberoptic snake/minicam, and a UT (ultrasonic thickness gauging) of the drum and quills, you should be able to get a better ideal of how the boiler is constructed and what condition it is in.

The center drum may well have been made from a piece of "extra strong" (aka, schedule 80) pipe. I doubt very much that it is cast iron. I would be more inclined to think it is wrought iron pipe. Wrought iron pipe was first made, prior to steel pipe. Wrought iron is what I call an "inconsistent product". It is often spongy or has "fibers" with stringers of slag in it. Its strength is a good deal lower than carbon steel. Wrought iron pipe was made with a heavier wall to allow for inconsistency in the strengths of wrought iron from one batch to the next, as well as to allow for a butt weld on the seam of the pipe. The nominal inner diameter of the old wrought iron pipe was pretty close to the actual diameter of the pipe as it came from the mills. Once carbon steel took hold for pipe, thinner walls were found to work as well or better than the wrought iron. The result was what became the ASTM (American Society for Testing Materials) standards for steel pipe, with a schedule of wall thicknesses. Schedule 40 became known as "standard weight", and schedule 80 became known as "Extra Strong". Possibly, your boiler drum is made from a piece of 4" schedule 80 steel or wrought iron pipe. I would go with the idea of schedule 80 because it has twice the wall thickness of standard weight pipe. For this design of boiler, with more holes tapped in it than remaining wall, the heavier wall would be desirable to compensate for all the tapped holes. In addition, the heavier wall would give more engaged length for the pipe tappings.

My guess is whomever built this boiler was someone who was a mechanic such as a machinist, boilermaker, or steamfitter. They had access to a drill press, pipe taps, pipe cutter, and pipe dies and diestock. They also had plenty of time to build the boiler. This was a lengthy proposition what with all the holes to be drilled and tapped, and all the pipe to be cut to length and threaded. The square-ended quills were likely done in a blacksmith forge. Back "in the day", maintenance shops and machine shops all had a forge and anvil. Pipe shops often had a blacksmith or two kept busy forging pipe support or pipe hanger hardware. Boiler shops also had a forge and anvil.

Whomever made your boiler was obviously at home in a shop with pipe tools, a drill press and a forge and anvil. The biggest mystery to me is how the boiler made steam. Boilers are designed to utilize natural convection to get circulation of the water within them, and a release of steam at the surface of that water. This porcupine boiler does not appear to have any kind of really easy or obvious paths for this circulation to occur. While the boiler did make steam, how efficient and well it made that steam is another matter. It may have rumbled and shook as it made steam. With some sort of blowtorch (or "blow lamp") type of burners -given the burner openings in the boiler casing- there may have been some very intense localized heating of the quills and center drum. The result was a kind of sporadic making of steam down in the boiler, with a gush of steam bubbles up to the releasing space, with this occurring in a continuing cycle.

For a small steam plant in a small launch, I think the builder/owner/operator was content just to have it make steam and run the engine in his launch. Whether the boiler shook, rumbled, and made steam in fits and starts and was not the most efficient show in town were nothing the owner/builder/operator concerned himself with.
The Shipman Boiler/Engine combination of usual reference included a boiler made up of quills - these placed on a flat header (must have been fun to stay this)

Below the "Boston Model" Shipman


Shipman had its origins in Rochester, NY and their first version was the "Rochester" Model, which IIRC had a porky more along the lines of Les'.


More information at Shipman Engine Manufacturing Co. - History | VintageMachinery.org

The Shipman engines were quite advanced for their time. Burning kerosene and self regulating as to fuel, water, and governed for power output.

Joe in NH
Thanks to Joe K and Joe M :)
After fighting things the last couple of days I FINALLY was able to remove the water column.All it is is a large pipe nipple with the ends reduced down by reducers.The fittings are threaded into tapped holes.Very crude and the large nipple appears to be schedule 40 as Joe referred to in his excellent summary on this type of boiler.Taking this thing apart has been a real treat..not a good treat either.

That water column was assembled from the bottom nipple up and required disassembly from the top union down.I couldn't just swing it down revolving it to unscrew it. It hit everything in sight including the leg riveted to the base which hold it to the plinth. Anyway Got all that off so tomorrow I'll remove the outer wrapper and we'll see what it looks like.

Joe..I have one of those camera's at work so we'll do an inspection internally like you suggested.What I find odd is the top cap is such a nice casting. Also the "swirling bowl" part of the burner inside the firebox is a nice iron casting.The bottom of the firebox is 1/4" thick iron tube or pipe with the inspection door opening cut out of it.Some of it is really nicely done and other parts of it seem so..well. At this point I'm not real thrilled with it.

However..saying that I fully intend to find out to satisfy Joe's curiosity (and mine) just exactly what is taking place within those short tubes. Joe..you explained very clearly how these tubes COULD work with the inner tube and perforations. Interesting what you said about the elbows turned "downward" directing the water path.

I can't say I am impressed with this boiler. If it had a "Shipman" or " Willard " tag..something I could relate to historically, I would be more excited about it. It is too early to tell. We'll just continue our investigation and make a decision later. I'm glad I bought the plant mainly for the engine and governor..plus the early steam fittings and 1/4 pint Powell lubricator. More later! :)

Thanks for the update on the porcupine boiler. From your description and photos, my feeling is this boiler was a "do it yourself" project, possibly done as a "government job" ( a job for home or similar use done in one's place of employment using shop facilities there).

I will be interested to hear (and see) what the "video snake" discovers inside the boiler. The "snake" should disclose the internal condition of the center drum and porcupine quills, as well as whether any sort of "inner quills" exist (per my hypothesis, above) to promote better circulation.

Getting a boiler like the one in this thread is, in my opinion, an even bigger unknown than the vertical fire tube boiler you restored and returned to service. That boiler was a straightforward proposition, easily inspected inside and out, easily UT's and calculations run... This boiler is a real enigma at so many levels.

Another hunch comes to mind here, and that is the design of some of the vertical boilers used on the steam fire engines- the kind that were pulled by horses. Some of those fire engines used varieties of water tube boilers fitted into casings looking much like vertical fire tube boilers. Water tube designs around a central vertical drum were sometimes used to promote very fast steaming and a high steam rate from a given envelope. The watertube design, aside from fast steaming, also kept the weight down- a consideration on a piece of horse drawn fire apparatus that rolled on steel tired wagon wheels, often over cobble stone paved streets. Keeping the weight and center of gravity down were a big consideration on a steam fire engine boiler, aside from needing to be able to raise steam in a hurry and make a lot of steam as the pumps often ran full bore with no letup for quite some time. I wonder if the person who built this porcupine boiler did not draw on some knowledge or experience with fire-engine water tube boilers.
Lester, IIRC "Live Steam" magazine ran a series on "How to build a porcupine boiler" back in the 1980s. Including the admonition to NOT use flow enhancers in the tubes - they had some rationale based on experimentation.

Still, this was a boiler intended for a launch.

Check out Live Steam Article Index

Joe in NH