Saturday, December 04, 2010

Back to the Techno-Mech lifestyle - Preview

A casual glance around The Make Blog gave me some potential projects to drool over and potentially practice my CNC programming and machining skills.

First off, a simple statement.  Most consumer products are cheap, not particularly durable, and... frankly, that's just fine for most people.  But some of us aren't "most people".

Sunday, October 08, 2006

More renderings

Here is the valve which will probably be used. The two o-ring (well, four) design pressurizes the end of the cylinder the valve is pushed toward.

Here is the 3 o-ring version. It's operation is the reverse of the other, and I believe as designed, it has a slightly longer throw. That can easily be tweaked though. An advantage of this design is it's completely closed, and potentially reversable by swapping the center Input with the two ends (exhaust). Probably more complicated than I want to deal with in this project.

Here is a view WITHOUT the structural / guide rails.

The following is a ghost view of the complete engine so far. If you look closely you can see how the crosshead interacts with the rails, and also the set screws that determine valve throw and end travel. It is likely I will include another set of (adjustable) positive stops for the valve to keep it's momentum from carrying it beyond the mark when pushed by the crosshead.

Saturday, October 07, 2006

Initials

Welcome to my engine page / notebook. The basic idea is that I'm building a three cylinder, double acting steam engine (although I probably won't have time to actually build a boiler or run it on steam, it will run just fine on compressed air).

The design has some similarities to the engine used in the Stanley Steamer of the early 20th Century. The major difference is that in my engine, valve timing will be controled by a toggle switch attached to the cross-slide, rather than the Stanley method of forward and reverse eccentrics on the crankshaft. In order to modify my design to accomodate a similar "instant reverse" feature, a separate camshaft would need to be added to control valve timing, OR the crankshaft could be lengthened, and the spacing between cylinders increased. Alternatively, I could remove the center cylinder and use that space for a linkage similar to that of the Stanley engine. Due to the modular nature of this engine (see rendering and sketches below), this would not be particularly difficult, though it would add significantly to the machining complexity of the engine... something I'm not sure I'll have time to accomodate.

After playing around with a downloaded evaluation copy of Rhino3D for about six hours last night, I came up with this:
(Click on the picture to make it bigger)

The only thing there that isn't pictured are the support rails. When included in the 3D model, it's hard to see anything else. But you can get an idea of what they look like by the grooves and slots in the cylinder blocks and crankshaft main bearing supports.

Because I don't have a scanner, here are some digital pictures of my notes: