Geared horizontal twin engine

[Brian Rupnow]

I like myself a lot better today. No taps were broken and all of the holes ended up in the right place. Tomorrow I can forge ahead with either the cylinders or the flywheels.

[Admiral_dk]

Success is often the best remedy to make you feel better - and it certainly beats the not so nice thoughts when things doesn't go to plan. Nice progress and parts Brian 

[Brian Rupnow]

Every day, a few more parts. Hardest job of the day was standing out in my unheated main garage sawing out flywheels from that piece of 6" x 1/2" hot-rolled steel. I need a new blade on the saw, and it doesn't cut very fast right now---and if you lean on it a bit then the drive belt slips. ---Thought I might freeze to death before I got the flywheels cut out. Tomorrow I hope to completely finish the flywheels.

[Craig DeShong]

Silently following along Brian.  This going to be an interesting engine.

[Brian Rupnow]

And today we have two lovely steel flywheels, bored, reamed, and keyseated. There is a lot of work in two flywheels cut from hotrolled plate, but they turned out very nice. These guys will end up being painted and polished, along with a few other accent pieces on the engine.

[crueby]

Great proportions on the flywheels, they look great!

[Brian Rupnow]

One of the things that I often have to ask myself, is 'What part do I make next?' Sometimes there is a logical chain of parts that must be made in a certain sequence, other times it doesn't much matter. When I threw together the 3D model of this engine, I designed a crankshaft without thinking a lot about how I would fabricate it. Today I had some design time available after finishing the flywheels, so I took a much closer look at how I would actually make the crankshaft. This was the result, and it looks easy enough, so I will probably work on it tomorrow.

[Brian Rupnow]

Todays work consisted of putting oil holes and galleries into the main crankshaft support block, and making all of the crankshaft parts and silver soldering them together. Highlight of the day was a visit from my friend Terry, a gentleman who shares a common interest with myself about building and machining small engines. We both sat around my office wearing masks and telling each other how tired we are of this damned virus thing. Terry has built a few of my engines, and does marvelous work.

[Brian Rupnow]

Tomorrow, after I completely finish the crankshaft, I will work on the eccentrics and eccentric straps.  In the past I have made one piece eccentric straps and a two piece eccentric to hold the straps in place. That works, but it requires rework to a standard socket head cap-screw to make everything fit into a small area. I'm going to do something a little different here. I will make the eccentric from one piece with a flange on each side to keep the eccentric strap in place. The eccentric strap will be two piece with #4 capscrews holding the two halves together. With this design I can use a standard #4 shcs with no modification, and the eccentric strap ends up being much simpler  to machine.

[Brian Rupnow]

Crankshaft is finished and installed. No real drama. I have to file off that little bit of key sticking out past the end of the crankshaft, and then I can move on to eccentrics.

[Brian Rupnow]

Every time I make eccentrics, I seem to find a slightly different way of machining them. These turned out quite well, and all I have to do now is drill and tap them for set screws. They do not get a keyway, as they have to be able to rotate on the shaft to set the timing.

[Brian Rupnow]

The eccentric straps are finished and installed. The flanges on the eccentrics keep the straps from moving side to side, and yes, they do miss the crankshaft throws when everything is rotated.

[Brian Rupnow]

Tomorrow I start making cylinders. These cylinders are a bit different, because there is no profiling on the outside. They are rectangular, but there is a lot going on inside. I have made the tapped mounting holes in the underside in exactly the same position as the tapped mounting holes in the topside where the steam-chest bolts on. Two ends are tapped for cylinder end-caps, and two remaining sides are blank. (Except for the exhaust exit hole).

[crueby]

Great progress Brian!


 

[Brian Rupnow]

Was I busy today??---Yes, you can bet your bippy that I was. 32 holes drilled and tapped, bore and air passages machined in. I've been at these cylinders all day, and I'm going upstairs to set with my good wife and drink rum now!!!