Thanks everyone for you thoughtful comments.
It's about time for a progress update isn't it?
I can't let you all to think that I've been just kicking back with my feet up on the desk or something like that.
So the first order of business since the last build update was to drill and tap the bottom of the engine frame to accept the engine's base plate. Then it was on to milling out the engine base plate itself. Another simple but yet critical part that needed to be made was the brass crankshaft bearing support tube. Once this part was made it was then pressed into the engine frame. The crankshaft is supported by two stainless steel sealed ball bearing which get press fitted into either end of the bearing support tube.
Now that the bronze cylinders have been made it was time to make the upper and lower cylinder covers. The upper (or top) cylinder cover is turned and milled from brass while the lower cylinder cover is made from bearing bronze since the piston rod will be passing through it. The lower cylinder cover is bored and tapped to accept a o-ring gland seal and a adjustable gland nut which will be made at a later date. Both the upper and lower cylinder covers thread into the cylinder and in the photos you'll notice the o-ring seal which keeps them steam tight. I've rubbed steam oil onto the sand blasted surfaces of the bronze cylinders and then wiped away the excess with a clean towel. I've found that this improves the look while preventing finger prints showing up on the surfaces.
The next interesting and somewhat tricky part that needed to be made was the brass manifold cover which bolts to the front of the engine frame thus sealing off the internal steam passages ways. I've dubbed this part the brass bat wing. I like to think that Batman would be flattered.
You can't have a manifold cover without a proper throttle valve/direction valve so that was the next part to be made. I also decided it was a good time to make the intake and exhaust manifold extension which thread into the rear of the main engine frame. So by this point I started getting impatient as always and decided to go ahead and paint the engine frame to see what it was going to look like since the prototype version of this engine I made earlier was never painted. After painting it I of course accidentally put a few small chips in the paint shortly afterward.
The two ridiculously long bolts holding the cylinders in place are only temporary until I get around to making the real trunnion shafts.
The engine is really starting to take shape now but there is still a ton of other parts that need to be made still to before I can even come close to calling this project done. Hope you enjoy the progress photos.
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Topic: The birth of the Cirrus V-Twin (Read 25763 times)