Stirlingengineforum.com

The current flywheel is fairly heavy (cast iron/steel), but I think I can probably add some weight to it. Any guesses on how much weight? I grabbed some dry graphite lubricant spray, and I've coated the aluminum pistons and walls of the cast iron/steel cylinders with that. I've also sprayed some deg...

Just curious: Is there any such thing at Teflon spray lube that sticks to the surface and stays there? I'll answer my own question...yes, looks like Teflon spray is indeed available. Here's a link: http://www.sealfast.com/d_teflon_spray.html Ahh...looks like something similar is available at Lowes....

Not sure I know what "shielded bearings" are. :razz: What's in there for the crankshaft are bearings with balls inside of a small open frame, the frames touch each other but prevent the balls from touching each other (if that makes sense). It's open on the side I can see, so I can try clea...

...Take the shields out of the inside side of the main ball bearing races and clean out the grease, lub with light oil. Ian S C Do you mean try this with the existing bearings? I've seen you suggest needle roller bearings before...is there some particular reason? Do they just tend to be lower-frict...

OK, got the cylinder heads off, cylinders off, rings removed...that helped, but still quite a bit of friction. Will try the teflon tape tommorrow. The piston arms seem to be pretty low friction, so I'll assume the bearings for the crankshaft are the next area to look. Any thoughts on what type of be...

OK, this compressor pump just came and I see what you guys mean. The flywheel is a stiff turn...wow! First I'll try removing the piston rings and see how much friction that alleviates. I've heard it mentioned that the bearings need to be replaced with something lower friction...where are the bearing...

So, there are a couple companies that make Stirling-based free-piston type solar generators (the type with a parabolic mirror focusing the solar heat on the Stirling engine parts). What is the benefit of this approach to solar-electric power generation versus just using PV solar panels? I know one c...

The Teflon plumber's tape is a good idea...thoughts on how to get it to stick in the piston groove?

Cheers,
Dave

Here's a great chart with lots of other material combinations. Note that the 2nd number with a superscript "1" is the coefficient of sliding friction if it's drastically different from the coefficient of static friction. http://www.engineeringtoolbox.com/friction-coefficients-d_778.html Fr...

This is worthy of being a separate thread...can threads be made sticky here? Friction coefficient of material against material : Aluminium - Aluminium 1.35 Aluminium - Steel .61 Cast Iron - Steel .23 Cast Iron - Cast Iron .15 Teflon (piston rings) - Steel .04 This list is compliments of Ian S C (ori...

Thanks Ian. From watching the Greenpower video's on this, I'm thinking it *might* seal well enough to just take the piston rings off and try that, we'll see. I'm not sure what materials this one is made from...it's black, so I'm hoping cast iron...the aluminum ones are usually silver, but I'll see w...

I've seen Telfon (PTFE) mentioned several times as piston ring material...how about Teflon rod for the actual piston material? Here's a link to a supplier: http://www.onlinemetals.com/merchant.cfm?id=214&step=2&top_cat=181 I looked up the properties...looks like Teflon has a max working temp...

I just snagged one of these cheap: http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=150474869445&ssPageName=STRK:MEWAX:IT And yes, I've read everything I could find about using a v-twin compressor pump as a starting point for an Alpha-type engine, and know it takes quite a few mods (but lo...

Here's an interesting design that combines the displacer and flywheel:

http://www.emachineshop.com/machine-sho ... ge341.html

Anyone tried building one like this? The simplicity of the design is appealing.

Dave

Good point about creating a less efficient "electric motor". :mrgreen: Still thinking "out of the box" here...external combustion, electrical resistance, electrical arcs, concentrated/point-focused sunlight, geothermal heat, nuclear reactions, chemical reactions, friction...what ...