I just finished my fourth engine, Elmer's fancy. Without a lot of talk, I departed from his design in several ways. I made the column of the engine wider and 'beefier', and added a pressed-in bearing for the pivot shaft up top. My piston is made of drill rod (2 pieces pressed together) instead of the threaded brass style mentioned in the plans. Also, I modified the valving so that the intake and exhaust ports exit out the sides of the column, instead of one in the back and one on the side as per the plans. Add a custom flywheel (bimetallic at that), and a 'fancy' nut/retainer to hold the spring of course.
Excuse the dust and drops of oil on her in the pictures, she just got her first run.
Piston:
View showing the bearing up top:
And three of the finished engine:
UPDATE 7-1-2011, here is the video!
<embed src="http://www.youtube.com/v/Pvxce5pIyLo" type="application/x-shockwave-flash" wmode="transparent" width="425" height="350"></embed>
Excuse the dust and drops of oil on her in the pictures, she just got her first run.
Piston:
View showing the bearing up top:
And three of the finished engine:
UPDATE 7-1-2011, here is the video!
<embed src="http://www.youtube.com/v/Pvxce5pIyLo" type="application/x-shockwave-flash" wmode="transparent" width="425" height="350"></embed>
Special thanks go to ArnoldB for his help on this project. Right now I have to run it using a basketball needle, which requires both hands (one to work the trigger on the needle, and the other to hold the engine against it). However, clear tubing is on its way, and a video will come as soon as that arrives...
