Potty three cylinder radial

[Gordon]

I am building the Potty Three Cylinder Radial (plans available on this site) and I have a couple of questions for folks who have built this engine.

(1) There is a tapped hole in the main body which takes a breather. The breather as drawn does not have a through hole to make it a breather. I assume that it should have a hole open to the outside. The breather seems unnecessarily large (3/8-24 tap) just to release some air. There is also a tapped hole in the bearing housing and I do not know what that would be used for.

(2) The crank shaft has a series of holes to connect the crank pin to the bearing housing. The crank pin also has flats machined on the sides. Why the holes connecting the crank to the bearing housing? Possibly for lubrication but you would have to fill the bearing housing with oil and it would soon all be transferred to the main body.

 

[Path]

Gordon,
Take look on the team build site ... your question may be answered there ... if not let me know and I will try to answer.

Good luck,


Pat H

 

[Gordon]

I found the team build. I had looked before and had not found it. It lead me to a build log on MadModder which answered my questions and even some which I did not realize that I had.

Thanks

 

[Path]

Is this the one you found?


http://homemodelenginemachinist.com/f33/anyone-interested-radial-team-buid-14618/

It's a long thread, but I believe we cover all the issues.


Pat H.

 

[Gordon]

Yes. That is the thread. I just went through the one on MadModder and found it useful. He did somethings different than I have done them and in some cases his way was better and in some cases my way was better, at least for the equipment that we each have. I even found one piece that I have to remake because I misinterpreted the drawings. My fault, not his. I will probably also go through the thread on this site soon.