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steam5

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Hi every one this is hoping you are all well.
With a lot of help from some friends I have managed to put some photos on (photobucket.com/charlesbuttigieg-steam) hope you like them.

Steam5
 
I am doing well, thank you for the good wishes steam5.

I see an engine of yours that intrigues me greatly

epicycloidgear.jpg


So I had to look up all the particulars for this type of crankless piston connection with a flywheel.

gearedstraightlinemovement.gif


;D I love it. That's so simple and elegant. (But that's a BUNCH of work on cutting those gears too!) ??? Maybe I'll put this one farther down my list; like number 5 or 6. Gotta learn to walk before I run. ;)

Thanks for the pics brother,
Kermit
 
Welcome steam 5. I enjoyed the pictures :bow:. And thanks Kermit for posting a nice diagram with explanation about this interesting mechanical movement. :bow:

Cheers,
Phil
 
I seem to remember a story (possible idiocy alert here) that, during the early days of the steam engine development - around the time of James Watt - someone had patented the typical crank arm used to attach the connecting rod to the crankshaft. As a result, engine builders, to avoid patent infringement, had to come up with alternate methods of interfacing the piston to the crankshaft. This epicyclic gear arrangement was one of the methods used to circumvent the patent.

One of Elmer Verburg's designs

http://www.john-tom.com/ElmersEngines/05_GearedA.pdf

uses this arrangement. Elmer used a ring gear purchased (big bucks today) from Boston Gear. Making a ring gear is really a job for a shaper - not impossible, but certainly not simple.
 
mklotz---Your reply is absolutely correct. James Watt could not use the crank, as someone else had patented it at the time he designed the first rotary motion steam engine, based on the Newcomen pumping beam engine.
 
Thanks, Brian. It's nice to know that my old brain still occasionally recalls stuff correctly.

Actually, if I had taken the time to Google a bit, I could have verified it. This Wikipedia article:

http://en.wikipedia.org/wiki/James_Watt

contains the following quote:

The field of application of the invention was greatly widened only after Boulton urged Watt to convert the reciprocating motion of the piston to produce rotational power for grinding, weaving and milling. Although a crank seemed the logical and obvious solution to the conversion Watt and Boulton were stymied by a patent for this, whose holder, James Pickard, and associates proposed to cross-license the external condenser. Watt adamantly opposed this and they circumvented the patent by their sun and planet gear in 1781.
 
mklotz said:
...circumvented the patent by their sun and planet gear in 1781.
Yeah, there were a whole lot of wacky things going on to circumvent patents back in the day. Half of the 'parallel' or 'straight-line' motion linkages for one..
 
mklotz---What is your past history /career profile. You seem to be one of the smartest (mathematically) people I have ran across on any of the forums I belong to. You are articulate, wise, and have an in depth knowledge of many diverse things.---I am not being facetious here---this is a serious question. Not something I would generally ask on an open forum, but your profile says that you don't wish to be emailed.---Brian
 
Brian,

I'm not aware that my profile says not to email me. If it does, please show me where and I will fix that. My email address is in my profile and, of course, you can always PM me as well.

I was born and grew up in Allentown, Pennsylvania. I detest cold weather so I moved to Southern California after graduating from college.

I'm a physicist by education (MIT and UCLA) but spent most of my working life as what can loosely be termed a "systems designer/analyst" in the aerospace industry. A lot of this work was "black" so I can't tell you about it unless I shoot you immediately after. Some of the non-black stuff I worked on included the backup navigation system for the LEM, ICBM targeting, attack submarine navigation and targeting, and fire control algorithms for high-energy laser weapons. I've worked on numerous satellite systems - mostly navigation systems but also fire control for Star Wars.

Much of this work involved writing extensive simulations of these systems so I became comfortable with computers and programming.

As you might expect, most of this work is anything but hands-on so I sought out a more mechanical hobby to provide a more tactile satisfaction than that supplied by my employment. My Dad had an extensive shop that included an old wood lathe. I was fascinated with this tool but was really overcome when I met my first metal lathe in high school shop class.

In the 70s I bought a Unimat and set about making my first engine. It didn't take too long to discover the limitations of such a small machine and I soon graduated to a full size lathe and mill in the early 80s. In those days there were no resources like this forum so, being a life long bibliophile, I read a lot about the hobby and its history.

I've never had a metalworking mentor so my skills, such as they are, are all self-taught - which often leads to unusual, some might say bizarre, solutions to problems. Being comfortable with math and analytically inclined, I often calculate my way out of shop conundrums rather than using more conventional approaches.
 
Marv:

In your profile, your email is listed as "Hidden". However, when YOU look at your profile, you will see it. (I had the same problem). There's a box to tick or untick in "Modify profile".

Cheers, Joe
 
PS Steam5

Sorry about wandering off topic, enjoyed you photos. Keep 'em coming!

Joe
 
Sorry about the thread hijack. Curiosity overwhelmed me.--Marv---this is what shows up when I tried to access your profile. It doesn't show up well here, but it says that your email address is "hidden".----Brian
mklotz.jpg
 
That is a very interesting mechanism indeed but I don't think it quite like Watts' original which did not use an internal ring gear. Watts' epicyclic mechanism used a spur gear rigidly fixed to the connecting rod. It rotated around the outside of an equally sized spur gear which was fixed to the shaft. A loose fitting link between the center of the outside gear (Planet) and the center of the inner gear (Sun) kept the two gears in mesh. Because the gears were equal in size it produced two revs of the shaft for each stroke of the rod. This link looked very much like a crank arm but because it was not fixed to the shaft as a crank would have to be, he was able to defend against infringement claims.

Watts' engine was a beam type and thus did not need to have straight line motion at that end of the beam. His parallel linkage at the cylinder end of the engine produced straight line motion on the piston rod. The linkage on Steam5's engine quite different in that it provides straight line motion for the piston rod but does appear to be attached to the planet gear by a short crank arm.

An animated view of Watts' gear is provided here:

http://en.wikipedia.org/wiki/Sun_and_planet_gear

I would really like to see a video of the engine running.

Jerry
 
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