The following could be called, “Yes, Virginia, there is a Santa Claus,” or, better yet, “I Can Now State Unequivocally That There Are Still Magicians!” No, I have not been smoking any illegal substances. Here is the whole story behind my 1914 Waterman B-2 marine engine:
In September 2008, I got a nice color auction flyer telling me that my longtime friend Howard was having the sale I’d been waiting for. All the antique hit-and-miss gas engines and accessories from his wonderful museum were going on the block.
When the day came I did not have to rush down early because I had already scouted everything. I had taken time to look it all over, take many pictures, etc. I did all the tire kicking and hood lifting (or what passes for it on old iron). I was ready. My brain thought there were two possible “apples of my eye” but my heart knew there was only one. It was a Waterman model B-2, copper-jacketed, magneto-sparked, twin-cylinder, 2-cycle inboard marine engine circa 1914. WOW!
I had never seen the B-2 in the flesh. I know that GEM is strictly G rated but there are so many, well, let’s say “earthy” references I could make about how I “lusted” after such a beauty. Now was my chance to possess one of my very own. I just had to be sure my arm stayed up long enough.
Anyway, I won the bid, loaded up my prize and headed home to really look it over and take photos.
Analyzing the Waterman
Now, I knew that some kind of exhaust manifold that connected the two flanged pipe stubs out of the cylinders was missing but, what, me worry?
I opened my Xerox copy of a Waterman catalog, circa 1914, showing my exact engine. There, in black and white, was the engine image including the manifold. In the picture the manifold was a lighter color (aluminum, like the crank cases) and extended along the whole length of the engine and more. It was bristling with ports, knobs, bosses and threaded openings. Hmm – I realized I didn’t actually need the manifold (now seen as a water-cooled unit) because I could just do what the last owner probably did which was to allow the engine to run without muffler or restriction to get the most RPM from it. I could do this if racing was my thing instead of authenticity. I began to remember how rigidly I had held up my hand at auction day. Could that have been a mistake made in the heat of passion?
Off to the Internet!
Enter OldMarineEngine.com (OME). This is a website for antique inboard engine nuts. It is a very helpful place to get information and ideas. I opened a new thread and posted a few pictures of the B-2 and innocently asked if anyone had any idea where I could get an exhaust manifold. I may have well asked for the keys to the universe or the map to Jimmy Hoffa’s final resting place. There were many comments and I realized quickly that a living, breathing B-2 was a rare thing indeed.
One gentleman mentioned that he knew how to get the manifolds for the K-2 Waterman (an earlier model) cast but said nothing about the B-2. After a week, I realized that nobody was going to show me their garage full of B-2 manifolds. I was stuck unless I wanted to hack something that looked a little like the manifold out of a solid aluminum bar (no thanks) or try to cast a solid look-alike using a borrowed B-2 manifold from a kind-hearted fellow collector. I would then have to somehow hollow out the “fake” using my trusty carbide air tool and a war surplus shaped charge. This did not look good.
In answering my B-2 thread, the man who had the ability to produce the K-2 manifold posted a detailed picture of a core box, pattern and finished manifold. Now, I know about casting and foundry work like I know about plutonium initiators and critical core design. I was surprised at just what had to be done to make a hollow space inside a casting (lead fishing sinkers in 10th grade was my casting experience up to then).
My curiosity piqued, I just had to e-mail the man back with questions. Turns out his name is Dick Alcock, a retired master pattern maker. Dick went through the basics of how he made the patterns and core boxes for the K-2 manifold. He told me what the foundry charged in the past for the “simple” K-2 casting and it seemed reasonable. We e-mailed back and forth more and also with Keith Billet, the OME member with a B-2 manifold who graciously offered to loan it to us as a pattern.
Dick then took a deep breath mentally and said something like, “How about if I try to make the patterns and core boxes so I can recreate the manifold in cast aluminum right down to specifications?”
Man, I was way out of my depth here. I really wanted the correct part and Dick looked like my best and only chance. I also came to feel, as the e-mail between us went along, that he wanted to test just how far he could push his own skills. (Kids, don’t try this at home unless you have a spectacular “drinking buddy” relationship with your local foundry manager.)
Making the blueprint
Keith Billet and his professional CAD system churned out several precision drawings based on his manifold which went to Dick by e-mail to use as the blueprint. The manifold is just two closed-end tubes, one inside the other, sharing a common open end plus some vicious complications. The inside pipe channels the hot exhaust and the outside pipe holds cooling water from the engine against the hot inner pipe to cool it.
To have the manifold cast, you just have to create the reverse of the real thing. Any place there is aluminum, there has to be an exact-sized space, and any place there is a space you have to put a sand “core” made to the exact size and held exactly in the same position. Everybody has “cast” a simple thing like a snowball. Your hands are the 2-piece mold. Now, picture making a snowball with a hollow inside cavity! Not so simple.
The work begins
Dick began by turning the wooden patterns starting with the shape of the outer tube. Keep firmly in mind that as your two hands need to separate to free the snowball, so does the mold. And many of the wooden pattern parts have to be made or cut in equal halves to allow placement into each respective half of the mold.
Tubes from the manifold to the engine stubs were not straight but curved, which Dick cut from a circular turning he made. Remember, these are hollow tubes and required the “cores” to create the void. All cores were made from foundry sand and phenolic resin. This mix is placed into a hollow core box created with (you guessed it) a wood pattern pressed into epoxy paste as a medium. The completed hollow space in the core box is then filled with the sand/resin mix and allowed to dry. These are called “air set” cores and are quite firm, according to Dick. Core material from the old days was made of clay, sand and secret stuff but it never really hardened and could fall apart in the mold, causing delays and much bad language from the molder.
This hardened “core” is then suspended inside the mold in exactly the right position as the “space” it is representing. While Dick took on the responsibility to make the accurate core boxes, the actual forming of the cores was done by the foundry workers near the day they put the whole mold together. Looking at the “hot exhaust gas” core, another vicious complication to keep in mind was that the core had to be cast in two precise mirrored sections, glued together and the edges trimmed before it could be part of the mold. The manifold was cast from 356 aluminum alloy which gives a very good finish on machined surfaces. Dick said he used the 3/16-inch-per-foot shrink rule for cast aluminum when designing all patterns and cores.
As I said, Dick is a “casting magician” but there was a whole raft of issues with dimensions, shrinkages, materials and processes which he had to discuss many times with his versions of Yoda and Obi-Wan. The experts opined that this was an 80-hour project (if it could be done the first time) and commercially was between $5,000 and $15,000 in value (GULP!). I can only shake my head in wonder when I tell you Dick did it in 50 hours at such a low wage that it would only be legal in a third-world country.
Later, Dick tapped into this whole other arena of professional machinist friends for the use of engineering machines I could only wonder at. For the project, he had to adapt a BIG radial arm drill press to align the tap while he manually turned the exhaust opening threads.
The end result
Finally, in February 2009, I received the completed manifold. It was beautiful and fit my engine like a glove! I could sense the new manifold cuddling up to my engine (spooning?) in anticipation of a long life together on the engine show circuit.
Contact Tom Stranko at 2478 Stephanie Lane, Binghamton, NY 13903 •