Kind of new member

[cfellows]

Hello Group,

I've been coming to this site for a few weeks now and have left a few posts. Guess my manners went on vacation for awhile, but they're back so I'll introduce myself.

I'm 63 years old (almost 64), live in Cave Creek, AZ, and have an office job with DHL Express, probably just for a couple more years. I've done a lot of woodworking for the past 40 years. Started out making furniture and cabinets, then graduated to making telescopes in 1999. I've completed somewhere around 30 telescopes in the past 8 years and have sold all but 2 of them.

I've also been into metal working off and on for probably 30 years and pretty seriously for the past 15. Mostly model engines and shop tooling. I got into gunsmithing recently and completed an air rifle from scratch, except for the barrel. I've built one IC engine, a number of steam engines, a stirling engine that runs well, and 3 or 4 flame suckers, none of which ever worked satisfactorily. Sigh...

Now I'm back into model engines. My current project is a two cylinder, open column vertical engine based roughly on Randall Cox's Open Column 6 cylinder. The crank throws are 180 degrees apart so it will have a syncopated sound like the old John Deeres and Listers. I just started it a couple of weeks ago and so far have the frame mostly finished, the crankshaft finished, and the cast iron flywheels partly finished. This will be a good sized project with a 1" bore, 1.5" stroke, and two, 5" flywheels.

Looks like a great group here and I look forward to getting to know a few folks.

Chuck Fellows

Some of my projects are shown at my website...

http://www.cfellows.com

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[Tin Falcon]

welcome looks like you will fit right in
Tin

 

[Bogstandard]

Welcome Chuck,
From the look of your website, who's been a busy boy then.
I'm sure you have a lot to offer us, and hope we can help you in any way.

BTW the vid on your site shows a lovely poppet valve engine running, could you explain the principle of it to us. Gear ratio of the cam, poppet valve, and how it exhausts.

John

 

[cfellows]

BTW the vid on your site shows a lovely poppet valve engine running, could you explain the principle of it to us. Gear ratio of the cam, poppet valve, and how it exhausts.

The engine in the video was originally built to test the idea of a hit n miss engine powered by compressed air. To accomplish that, I needed a valve arrangement that is operated with a single push rod. The video shows the engine running as a standard 4 stroke engine with a cam operating at 1/2 the speed of the crankshaft. I later added a governor and turned it into hit n miss operation. It runs, but needs additional work since it "fires" too frequently. The following text and pictures explains the principle of the valve operation.

Only a single push rod is needed to activate the air inlet valve at the top of the stroke. Once opened, the inlet of high pressure air pushes the free piston (purple) in the head downward closing off the exhaust port and exposing the cylinder inlet to the air input. This simulates the firing cycle. At bottom dead center, or before, the inlet valve closes and the spring behind the free piston pushes it back to the top. This exposes the cylinder inlet to the exhaust port and as the power piston returns to top dead center, air exhausted out the exhaust port. As long as the inlet valve stays closed, the power piston can travel up and down as many cycles as wanted with little air resistance since the exhaust port stays open as long as the air inlet valve is closed. This valve arrangement works for 2 stroke, 4 stroke, 6 stroke, or hit n miss. You only need to worry about the the inlet valve timing - The exhaust takes care of itself.

 

[rake60]

Welcome Chuck

I've visited your website in the past.
It's nice to be able to meet the person responsible for it.
Very nice work you do there!

Rick

 

[Bogstandard]

Chuck,
That explanation is absolutely great, couldn't have asked for more.
Many thanks.

John

 

[wareagle]

Chuck, welcome to the site. You have turned out some nice engines! We look forward to seeing your future projects as well!

 

[wareagle]

Chuck, it is looking good. You'll have it wrapped up before you know it.

I like the way the cylinders look like they are molded together. Looking forward to seeing the finished product! Nice work!!

 

[cfellows]

Got some more bits done in the past week or so.

I got pretty far along with the heads - they were my biggest worry! I still have to thread the spark plug holes. I have a m10 x 1 tap, but don't have the 9mm pilot drill, so had to order one from McMaster Carr. I need also need to make and install the valve guides and do some milling where the intake manifold will attach. Finally, I have to flatten one side of each head so they'll fit together on the cylinders.

I also got the crankshaft and bearings mounted so I can get a better idea of what it's going to look like.

 

[Bogstandard]

Lookin' good Chuck.
Will you be using contacts or hall effect for the ignition?
I used hall on my last petrol jobbie, so much easier to make and adjust, plus a lot more reliable, but doesn't quite have the same nostalgic look.
For fuel I used Bob Shores mixture of unleaded pump with 5% WD40, shaken, not stirred. It keeps the top end nice and clean.

John

 

[jgarrett]

Chuck, Tell me something about those pretty spoked flywheels you are using on a lot of your engines. Do you cast the, buy them in a ruff state. Are the available in different diameters??/
Thanks,
Julian G.

 

[cfellows]

At some point I'd like to try the Hall effect, but have been reluctant to give it a go for the first time. Points and a condenser just seem a lot simpler, not to mention cheaper.

There's still a few things I haven't thought through, but hopefully I haven't built in any showstoppers, so far.

Chuck

 

[Bogstandard]

Julian,
LMS do cast flywheels.

http://www.littlemachineshop.com/products/product_search.php?critFast=flywheel&B1=Product+Search

Chuck,
Don't know about that, I used the TIM 6 system, it is cheap and works a treat.

http://www.jerry-howell.com/IgnitionModules.html

Instead of making a cam, you just use a plain disc of ali with the magnet epoxied into a hole on its edge. Jerry was very helpful when I explained that the text was a bit misleading. He did all the calcs for me and emailed me back within a few minutes with the correct size of disc to use with my engine, and it started almost straight away, just needed to retard the ignition a bit.
Definitely something to consider in the future.

John

 

[cfellows]

Hmmm, with a Hall effect setup, it seems like there might be an opportunity to combine the distributor with the disk carrying the magnets...

 

[Bogstandard]

Chuck,
It is even easier than that with a distributor.
All you do is mount the sensor and magnet inside the dizzy at the correct gap then use an interrupter disc with slots in to to make and break the sense.
Like this one for a V8.

http://www.nvbackflow.com/engines/hall effect disk.JPG
http://www.nvbackflow.com/engines/hall effect Brkt3.JPG

The other way is even easier. If your cylinders fire at 180 deg apart, use a lost spark system and do away with the dizzy altogether. Just fire both plugs at the same time (using the appropriate coil). This is standard practise on twin cylinder engines of this configuration.

John