Single Cylinder Opposed

[rdean]

Thanks Boswell

Just one picture today of the base plate for the engine. I am at the point that I want the engine to be more stable so it is easier to work on.
Nice piece of poplar with a clear finish.


Thanks for looking
Ray

 

[rwm]

Really looking great. This is my favorite engine so far.
How did you attach the brass exhaust tube to the valve? I see no solder line. It's a shame you can't get brass colored solder!

Edit: Turns out you can get brass colored solder. It has a pretty high melting point. I have never tried it.

 

[rdean]

Thank you Robert I'm glad you like it. The exhaust pipe is threaded into the valve guide.

I have been concerned about the unbalanced upper piston assembly. I weighs 9 oz including the outer connecting rods. I am going to try to counter balance that load by adding weights to each of the flywheels. I have no way to calculate the weight of a piece of brass 0.312 thick and of this shape. So I just made them to see.


This is what they look like installed on the flywheel.

It turns out that each weight is 2.4 ozs or a total of 4.8 oz.

It does help with the vibration but I don't think they are heavy enough being mounted at this location.
I am going to leave them like this for now as it would be possible to remake them and mount them further out on the flywheel later if needed.

Thanks for looking
Ray

 

[rdean]

I put 4 rubber feet on the base and mounted the engine.


I remember now why I have been staining the engine base boards a dark color unlike this natural finish. This will really show any marks or stains and I will be kept busy wiping it down.

I made and installed a magnet wheel and the hall sensor.


Thanks for looking
Ray

 

[Boswell]

While it might be more work, I like the lighter color base.

 

[rdean]

I like the lighter color base.

So does my wife.

The original gas tank that I made for my six straight engine was too small so I put it on the shelf and made a larger one for that engine.
It should be about the right size for this engine so I made a 4" tall stand and mounted it on the base.



I set the ignition timing, the valve timing, and now that the fuel system is complete the only thing left to keep it from running is the rest of the ignition system.

Thanks for looking
Ray

 

[heli_av8tor]

Your first post on this engine was Aug 1st. One month later it is almost ready to run.
This build series would take several years if it were my project.
Looking forward to watching the run video.
Tom

 

[rdean]

Tom I am retired and married so that should explain my time in the shop


I was going to make a nice box for the ignition module and the batterys but since the engine itself is well exposed I decided to leave them out in the open also.


Yes it does run.
It wasn't the easiest engine to get running but not so bad either.

No video yet even with the brass weights it bucks like a bull rider.
The counter weight calculator I was using told me that I needed 6.6 oz and I had 4.8 oz on the flywheels now so make some bigger weights.
This shows the old and the new counter weights.


The new weights are 3.3 oz and are mounted 1/2" further out on the flywheel and according to the calculator that is the perfect location and size.
I didn't get a picture of them installed but just went right for a trial run. Even thought I had the base held down with a screw clamp it was immediately evident it was a lot worse.
I am thinking the counter balance for a rotating object is different that just being in static balance so in frustration I removed all the flywheel weights and gave it a run.

It still has some vibration as seen in the fuel in the gas tank jumping around but not as bad as I had expected.
It is a success in that it does run but I am not happy with it as is.

This is not over and I will find a way to minimize the bucking and tame the beast.

Thanks for looking
Ray

 

[Chris Hamel]

Yay! Vibration or not, it is great to see it running

 

[Jake M]

Yes it does run.
It wasn't the easiest engine to get running but not so bad either.

Nice! That can't be an easy one to dead recon. That's awesome.

I am thinking the counter balance for a rotating object is different that just being in static balance so in frustration I removed all the flywheel weights and gave it a run.
It still has some vibration as seen in the fuel in the gas tank jumping around but not as bad as I had expected.

I wondered about this. I know conventional V engine crankshafts are balanced not directly opposite the weight. (If you take it that far, machining and manufacture have made this much less rewarding than it once was...).

So I'm looking at that, thinking, not knowing... You have a different situation than a "conventional" engine. I wonder if making the lower piston heavier, to match (or at least reduce) the weight difference between the upper piston and rods as a group, and the lower piston and rod as a group.
At that point, my monkey brain is thinking (on a holiday weekend... There may or may not be rum), but at that point, it seems, at a brief thought, if the "up and down" component could be self cancelling, then the upper and lower connecting rods might well still be balanced by the conventional means.

Just speculating though. Don't take any of that to the bank without counting it first....