Vertical Cylinder I.C. Rupnow engine

[Brian Rupnow]

Okay, I admit, I'm playing a bit here. I wanted to see how a vertical cylinder 1" bore x 1 1/4" stroke open crankcase engine would look. It looks good so far, but without a cylinder head and ignition points yet. Probably will go for an atmospheric intake valve.

[Brian Rupnow]

I think I'm going to try something different this time, rather than using my old tried and true early Chrysler ignition points. I've seen a couple of builds now where people have used Tecumseh ignition points which can be operated by a pushrod, rather than having to ride directly on the ignition cam. I can see where that would open up a world of choice in terms of where the points could be positioned on the engine. If anybody knows the model number or part number for these Tecumseh points please let me know.

[Brian Rupnow]

So, this design has got me through a rainy Canada day.  Good wife was busy all day doing financial books for various and sundry poor folks (read "relatives") and didn't want to be bothered, so this was a fun way to spend a day. I still have valves and ignition to play away at, but I'll wait for another day to do that.

[cfellows]

Hey, Brian, how about considering a hall sensor ignition.  That also gives you a lot more options on where to mount stuff.  Hall sensors are very small and cheap and can be triggered by a 1/8" diameter, 1/16" thick neodymium magnet.  The circuit can be powered by 3, AA cells which will last a very long time.  Since they don't require much power, you can trigger them from a crankshaft mounted magnet instead of the cam if it's more convenient.  This makes them fire every revolution, but doesn't cause any problem.

Chuck

[Brian Rupnow]

So there we have it!! What a neat little engine. The overall sizes haven't changed from the drawing that was posted earlier. This is a very simple engine, with a throttle style carburetor, no "hit and miss".  I still have to sort out the ignition system, but this engine is about as simple as the Webster. I will post more as I get time, but it will go quickly. I'm interested--If I build this and post the drawings as .pdf files, who would be willing to build it? It would be a "build along with Brian" sort of thing.

[Brian Rupnow]

Chuck--For me to buy all of the components from Roy Scholl or a similar supplier, ends up costing me about $100 for all of the components, batteries, switches, etcetera, when I go the magnet/hall effect sensor route. If I just buy points and condenser and a switch, it costs me about $20.00. I have my "coil in a box" that readily transfers from one engine to another, and a small wet cell 12 volt garden tractor battery that does the same. It's just a matter of economics.---Brian

[Brian Rupnow]

Oh Oh---I've just blown up my mouse---Its been getting jumpier for about two weeks, with the pointer dashing off on side trips across the screen without my intervention.--So--I just sprayed the underside with eyeglass cleaner and scrubbed with a toothbrush, then wiped it dry. Now it doesn't work at all!!!---Damn!!! I've borrowed the mouse from my wife's laptop (she uses the built in track-ball anyways.) but it is a different size than my old mouse and feels really weird.

[Brian Rupnow]

I bought a new "mouse" and got it up and running. That old mouse lasted about 12 or 13 years, so it doesn't owe me any money!! I really, really like the look of bronze for a flywheel, but Oh my God, it's expensive. I think I have enough of that big bronze weight that I salvaged from the landfill to make one more nice flywheel, but it's going to be a close thing. The piece I have left is 5 3/4" diameter x 1 3/4" long.-I may have to turn half of it into chips in the lathe, because there is no good way to hold it to saw it in half. All of my saws are too light anyways. I've been getting 7/8" lengths sawed off it at my local metal supplier with his giant self-feeding bandsaw, but the last time he cut a length off he said that he couldn't make any more cuts.

[Brian Rupnow]

Since I already have a couple of people who want to start on this project, here are a couple of parts to get you started that aren't going to change.

[Brian Rupnow]

And a few more pieces that aren't going to change.

[Brian Rupnow]

A word about the gears used in this engine.---I have a set of 24 dp gear cutters, and will be cutting a 30 tooth cam gear and a 15 tooth crankshaft gear. if you happen to have a set of 32 dp gear cutters, then a 40 tooth and a 20 tooth gear will give you the correct ratio and center to center distance of .9375" which is critical to maintain. For those of you who have "mod" gear cutters, can someone please check and see if there is a set with 2:1 ratio that have a center to center distance of .9375"(23.81mm)

[Brian Rupnow]

EDIT--EDIT--EDIT--I just discovered that the starter hub wasn't going to fit onto the flywheel, the way it was dimensioned. I have modified the flywheel drawing and the starter hub drawing to reflect these changes. Sorry if I screwed anybody up. The corrected drawing are going into the pdf files today.---Brian

[Brian Rupnow]

Okay--One more part--and only because I'm still trying out new mice. I didn't like the first new mouse I bought, so this is a trial with the second new mouse!!

[Brian Rupnow]

So---here are the two most complex parts on the whole engine. The cylinder is very straightforward. The cylinder head is more complex, and will require some careful thought before starting to "carve metal". At this stage of things, I'm only posting .jpg files, because some of the web-sites I post on don't have any way to post a .pdf file. If somebody really has a "Jones" to start building, email me  at brupnow@rogers.com and I will send you a .pdf file. I will make a complete set of pdf files after I have completely finished all of the design work. I am going to build this engine myself, but not until I have secured and modeled a set of Tecumseh points and figured out just how the ignition is going to go together. Regardless, the cylinder and cylinder head aren't going to change.

[Brian Rupnow]

It's the end of Canada day long weekend. I didn't work on this all weekend--honest.--But I did start it Friday morning. It's amazing how much stuff actually can be designed/modelled/detailed that isn't affected by the ignition points question. Here we have the valve, with friends.