Sideshaft i.c. Horizontal engine

[Brian Rupnow]

The last step, after the recess is machined in both sides of the flywheel is to hold the flywheel in place by expanding the chuck jaws inside the outer rim, and machine the outside diameter to a nice finish. The last steps of course, will be to put in the "lightening holes" and a couple of set screws and a keyway.

[Brian Rupnow]

I looked in my broach kit for the appropriate broach for a 3/8" hole, and I see that some ham fisted bugger has broken my 3/32" broach!! Then I went online to search for a replacement. Happens they have them at Fastenal. Hey!!! my kid works at Fastenal.-C'mere kid!!!--Can you get one of these things for me?--Sure Dad.--Somebody up there loves me!!!

[Art K]

Brian,

Maybe I'm slowing down in my old age.

Nah.. It's just careful attention to detail, wonderful looking rod by the way.
Art

[Brian Rupnow]

Both flywheels are turned now, but still need cosmetic holes, keyways, and set screw holes. You can see in the pictures how I kept both flywheels equally spaced about the center of the cylinder. This required a very large cavity in the gear side flywheel, but it clears the large helical gear by about .025", which is what I had planned.

[Brian Rupnow]

Once the holes are drilled in the flywheel webs, they really start to come to life. I can't do much more on them now, until I get a new broach.

[crueby]

Those holes really change the look a lot!

 

[Brian Rupnow]

All the things I have done so far are just repeats of parts and operations that I have done many times before. The exciting part for me is about to begin, up at the cylinder head end. I have actually made the rocker arm and exhaust valve and sideshaft cam on my previous sideshaft hit and miss engine, so that's not entirely new either. The overhead intake valve and rocker mechanism will be "sorta/kinda" new to me. I am not going to commit at this time about the position of the fuel tank. There is room enough to squeeze one under the cylinder, but after all the issues I had with my previous engine has made me a bit leery of fuel tank positions. The cylinder head, although not terribly complex, is going to be "interesting".  It can be made from a length of 2" x 1" aluminum bar.

[Brian Rupnow]

I've been setting here studying the two raised bosses on the face of the cylinder head in the above picture. They look nice, and they both serve a function. I'm just not 100% sure that I can make them. If I made them rectangular they would still function, but it wouldn't look nearly as nice. But--if I make them rectangular, I can set the part up on my mill table and use the boring head with a reversed boring tool and round the perfectly circular boss down to the surface of the longer raised portion.--Then how do I get the corners rounded on the longer raised portion?

[Brian Rupnow]

Okay--Minor design change here. That round boss was only there to give enough material to screw in an exhaust pipe. I have removed the boss completely and went to a flange mounted exhaust pipe. This lets me change the other long boss to be circular, which gives me sufficient thickness to screw the sparkplug into and makes machining a lot easier. Now it can be done on the lathe with my four jaw chuck.

[Brian Rupnow]

The block which will become the cylinder head has been machined to correct overall dimensions. It is set up in the four jaw chuck, and the first cavity machined into one side. This is the side which fits against the cylinder, so the recess just formed fits over a register turned on the end of the cylinder. While it is still in this set-up, I have drilled a 3/16" hole thru, so that when I flip it over to machine the far side I can pick up exactly the same center. eventually that 3/16" hole will be opened up to accept a sparkplug with a 10mm thread on it.

[Craig DeShong]

Brian, I bought those same gears off Ebay awhile back and was shocked at the size of them when received.  They were way to big for the contemplated project. Looks like you found a use for them though.  Following along as always 

[Brian Rupnow]

Part has been flipped over in the four jaw, and machined so as to leave the boss which the sparkplug fits up against. This is the last "on center" work that I have to do, so before I tear down this set-up I will drill and tap the sparkplug hole.

[Brian Rupnow]

The burn chamber has been milled. My gimpy back is starting to talk to me, so I'll finish this cylinder head off tomorrow.

[Brian Rupnow]

Jeez--I may have to rebrand this engine as the "Cyclops".

[Brian Rupnow]

Hi Craig--Glad you stopped by and said Hi. I kind of got the cart ahead of the horse here. I really should have built the piston next, but I was so intrigued by the shape of the cylinder head that I had to make it first. Your engine is looking very good, I follow your posts quite closely.---Brian