Nemett Jaguar--Canadian style

[Brian Rupnow]

After much searching, I found a fan at Acklands-Grainger, aluminum, 10 blades, 2" diameter, small hub bored for 3/16" shaft. Its about 21 down from the top of the attached link. The store in Barrie was able to bring it in for me, but its going to take about a week. That's fine by me---I don't feel like any more machining right now anyways, at least for a while. The engine is running excellently, and I'm not going to mess with it for a week. I did download 9 pages of information on making piston rings that Steamer had posted as a pdf file. The cylinder now has such a high polish inside from running the Viton ring that I may just build a water cooled cylinder and a new piston, and play with that until I can make a set of rings that will really seal.
http://www.grainger.com/category/fan-blades-and-propellers/hvac-and-refrigeration/ecatalog/N-jr8Zh9e

 

[hedgehog]

well whats next? when the weather turns this fall you will have to build something Please say V8 , id love to see your skill and artistic slant on one.

 

[Brian Rupnow]

Hedgehog--Next will be to get the fan mount and housing fabricated and installed, then try my luck again at the cast iron rings. A V8 is not in my future. I do all of my machining manually, no CNC. As a consequence, there is simply too much machining for my taste in an 8 cylinder engine. I would rather stick with new and different (to me anyways) one and two cylinder engines.----Brian

 

[Brian Rupnow]

I've been playing around this morning, designing a shroud for the 2" diameter fan made from a short piece of automotive exhaust tubing, some 1/2" diameter hubs, and some 1/16" diameter spokes to hold the hub in place. Hubs will have brz. or brass bushings with 3/16" bore. At this size I can actually set it in line with the flywheel and just come in underneath the exhaust header. I haven't shown the pulley and shaft yet, but would pick up the o-ring drive from the drive hub, not the flywheel. This is a lot more aesthetically pleasing to me than the previous fan design. Still haven't shown mounts yet, but I can't really do anything until I have the fan blade here.

 

[gus]

Very good looking fan and shroud. Brian has 1001 design ideas. Quick & fast on the draw.th_wav

Now looking at mini computer fan if engine heats up to fast. May put in water-cooled jacket and radiator.

Foot Pedal Speed Controller for fishing line spooler done and been on my mind for months and now R.I.P. to allow Gus to move on to Cam Cutting with peace of mind. Some prepping work required to get good cams.

 

[Brian Rupnow]

Hi Gus--good to hear from you. A mini computer fan will work, but they have an enormous hub in relationship to the length of fan blade. This is not problem if you want to leave them electrically powered, but if you drive them with an o-ring drive off the engine that big hub isn't moving any air. That is why I searched for a small diameter fan with a small diameter hub. If I were to start this project over again, I would go water cooled. You however, have already made your air cooled cylinder---in fact I don't think the Lynx plans even have a water cooled option, do they?---Brian

 

[Brian Rupnow]

Okay--I think I have the final draft--(pun intended). I decided that the 1/16" diameter spokes might be a bit difficult to fab properly, and the way I had things the fan would have to be trapped inside the cage as it was welded up. This is never a good idea. This morning I was working on supports, and decided to go with one support off a head bolt and one support off a cylinder bolt. As I was doing this, I decided to remove the spoke and hub assembly from one side of the tubular guard and cantilever everything off the side facing out away from the cylinder. This let me replace the round spokes with 3 pieces of 1/16" steel plate and the fan is no longer "trapped" as it can be installed from the open side of the guard which faces the cylinder before it gets bolted in place. There will be a 3/16" bore bronze bushing in the hub. The pinkish colored pulley (5/8" outer diameter) and 3/16" shaft will be silver soldered together. The fan hub is attached to the shaft with set screws. The 1.5" diameter drive hub attached to the face of the flywheel will act as the driver for the o-ring drive belt. Thus the fan will rotate at a bit more than twice the speed of the engine.

 

[doubletop]

I don't think the Lynx plans even have a water cooled option, do they?---Brian

Both have a water cooled option, I did the Bobcat water cooled and glad I did with the problems you are having. The second cylinder wouldn't get as much cool air as the front one.

I did the Lynx air cooled.

Pete

 

[doubletop]

Brian

Find a copy of the John Bogstandard instructions on hand machining flywheels. You could make that outer casing from one piece of aluminium. I'll see if I had a link to in in my French Beam engine write up

http://madmodder.net/index.php/topi...PHPSESSID=pmr4olh1c90iclecgvtpfmhmf3#msg55366

Pete

 

[Brian Rupnow]

Doubletop--I know I could make it from one piece, but I like fabricating with mild steel as well. What I have shown poses no real problems. Remember--in my previous 40 years of building hotrods I probably sewed together 300 old car bodies, where I had to create more metal parts with hammer and torch than the cars had on them.----Brian

 

[doubletop]

Brian

I was more thinking along the lines of making it out of a material in keeping with the rest of the engine.

Pete

 

[Brian Rupnow]

This morning was show down time. I had finished the shroud and brackets for the fan yesterday afternoon, and painted the shroud. This morning I got up and added some set-screws to the fan hub, and made up a shaft and pulley for the fan. I was very fortunate in finding a rubber o-ring of the correct length, and the fan was installed on the engine. I am very pleased with the results, and the 2" diameter six bladed fan which is travelling approximately at twice the engine speed puts out a very noticeable breeze over the cylinder cooling fins. The engine exhaust is a bit smoky, because I was running some two cycle oil with the naptha fuel to provide lubrication for the Viton piston ring.--The oil to fuel ratio is 1:20, but I think I can safely cut that back to about 1:35 for future runs. The engine has a wet sump and splash lubrication of the con rod big end.
[ame]https://www.youtube.com/watch?v=XVPX5MXDXrQ[/ame]

 

[johnmcc69]

Nice job Brian! The fan looks great.

John

 

[Tanshanomi]

As I said in another thread, I bought my new SB 8K to make parts for my vintage motorcycle project, and just happened to stumble on HMEM while Googling information about my lathe. I had never considered ever making a model engine, but I read this thread from front to back and it has really inspired me to start thinking in that direction. Your detailed and clear record of the build process is very useful and appreciated, and what a great little engine you ended up with! Glad to see you've gotten it into "fan"-tastic shape (sorry, couldn't resist the pun). Thanks for all the effort documenting this.

 

[doubletop]

Brian

That's looking really good and those viton piston rings seem to do the job. From my experience and the videos I've seen of others plenty of oil gets past the CI rings. The handle of your ignition box would then be covered in oil.

If I ever get round to the flat 4 version I have in mind, then Viton rings will be the way to go. There are no drawings for a flat 4 but if you look at the drawing for the bobcat in-line twin there is plenty of room on each of the journals for another conrod. Make the journals at 180deg and not inline and you have a flat four twin cam.

Pete

 

[bmac2]

Great looking and running engine. Glad to see you’ve solved the cooling problem. So any thoughts of making it do some work?

 

[Jasonb]

Pete you can get a more compact engine with a central single cam, just put two of these end to end.

 

[Brian Rupnow]

No work yet for the Canadian Cub. I still want to make a new piston with cast iron rings. Jason--very sharp looking engine.---Brian

 

[BronxFigs]

You guys amaze me every time.


Frank

 

[doubletop]

Pete you can get a more compact engine with a central single cam, just put two of these end to end.

Jason

I had wondered how you were going with your twin but I thought you were going to do a V? Flat makes the ignition timing easier. I'll guess you have a thread somewhere that I haven't found.

I had considered a single cam but I haven't seriously looked into any design other than looking at the existing drawings. For the single cam I assume you have some long followers and some way of supporting them?

Is there a link?

Pete