This is a short 3-minute video by “rbandes1″ that shows and explains the operation of the “Jingle Bell Steam Engine” he made. It was built from free plans provided by Professor Nial McCabe, who teaches Engineering Technology at the County College of Morris in Randolph, NJ. Professor McCabe has one on display with a main bearing that has become loose from heavy use. As a result the the flywheel lightly touches the frame when it turns, creating a “Jingle Bell” sound. That’s how it got its name.
This must be a popular engine because I also found a third set of drawings for it. Donald Neisler modeled it using Solidworks (you’ll need Solidworks or compatible software to view his CAD drawings).
On his blog featuring model engineering projects, Adam Richard Cooper has intricately detailed plans for making a Model Watt governor–the part that regulates the speed of steam engines by acting as a negative feedback system–that he designed himself. His post includes construction notes and CAD drawings along with a large photograph of the completed governor. He notes that his design is hand-cranked and lacking a valve lever, which he didn’t have time to complete.
At his blog Adam has other model engineering related posts including a review of tungsten carbide tipped tools for the lathe and a project that makes two cones joined at bases, which, when set at certain angles, appear to roll uphill.
MachinistBlog.com is pleased to announce our support for Copenhagen Suborbitals, a small non-profit suborbital space endeavor led by two guys with big brass ones. If they are successful Denmark will become the world’s fourth nation to launch a man into space, after Russia, the United States and China. In addition to wishing them well we have donated $10 to help their efforts :-)
Seriously, I think what Kristian von Bengtson, Peter Madsen and their small group has accomplished is pretty impressive, especially on a budget that is considerably less than $100,000.
Here are the pertinent facts
Their rocket is designed for sub-orbital flight. The same kind of flight that made Alan Shephard the first American in space.
Their astronaut will have very little room to move and will be “half-sitting, half-standing.” A position they think he’ll be able to withstand because launch forces are expected to be less than 3-Gs. The first few test flights will carry a dummy that will be used to test that theory. One of those flights is expected to take place within the next couple of weeks (and very likely within the next few days).
The booster is somewhat unusual. It’s a “hybrid” because it uses both liquid and solid propellants. Liquid oxygen is used for the oxidizer but I’m not completely sure what kind of fuel it will use. I believe it’s going to be polyurethane. They’ve also tested paraffin and epoxy. (That’s right, plastic, wax and glue.)
By the way, there is a machining angle to this story. The photo below shows the booster’s graphite nozzle being made on a lathe.
Even though YouTube seems to have umpteen million videos about machining I’ve found very few that will you show how to grind HSS bits for a metal lathe. And most of them show it being done on special grinders or with the help of jigs and accessories that most of us don’t have. These four videos by Tubal Cain, the author of many books about machining and metalworking, are among the few I’ve found that will show you how to do it free-hand on the kind of grinder most home machinists have. [This is not the same Tubal Cain who wrote more than 20 books and 200 articles about machining and model engineering. That was the late Englishman T. D. Walshaw who used "Tubal Cain" as a pen name. This "Tubalcain" appears to be a retired shop teacher living in Illinois. - Rob]
The videos are good, but not great because they’re too long. “mrpete222″ doesn’t get to actually showing you how to grind a bit until the fourth video. During the first three he discusses the shapes and angles of the various kinds lathe bits using large wooden models that make it easier to see what he’s talking about. He also discusses the tool bit holders used by older lathes, which hold bits at an angle so they don’t need back rake added to them.
I’ll admit I’m not real good at grinding lathe bits because I usually use carbide inserts. But I did learn a lot from these videos including these two great suggestions:
Use lay-out dye and mark out the angles you need to grind
Practice on mild-steel (keystock). It’s cheaper and grinds faster.
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