Triple Orphans

[steve-de24]

Very nice work Jo.
Steve

[kvom]

The plans I have show the eccentrics as a single piece for both the forward and reverse, with a fixed angle between them.  Trying to understand why all three aren't the same.

[Jasonb]

Middle one has to be split so you can get it on the crankshaft.

Good to see you making some swarf again Jo.

[Jo]

Thanks guys 

The plans I have show the eccentrics as a single piece for both the forward and reverse, with a fixed angle between them.  Trying to understand why all three aren't the same.

The LP and IP eccentrics have the same angle between them = 150 degrees, the HP is 120 degrees. The IP eccentric has to be split to get it on the crankshaft, this is tricky as you have to split the eccentric and put the two joining screws in the right sort of place so that they survive turning the two lobes. I did a practise one first 

Jo

[vcutajar]

Good to see you back at the orphans.  Missed them.

Vince

[kvom]

That explains part#27.  Thanks.

[Dave Otto]

Hi Jo

Good to see you working on the triples again; you need to get them finished up so you can play with your Christmas presents. 
Like I should talk


Dave

[Jo]

Christmas presents    I wonder what they could be 

Dave your Pacific Vapor Engine casting set has been good value for money  just look at how many years worth of fun and enjoyment they have given you   

Jo

[Dave Otto]

Yes it has; and I have enjoyed every minute of it. Although I am looking forward to working on something else.

Dave

[Tennessee Whiskey]

That's funny Dave , that's what I said after my divorce 

Cletus

[kvom]

Getting back to the eccentrics, they have a rib on the center, and the straps have a matching groove.  Wondering how you machined the groove and how close a fit is needed?

The eccentrics themselves look easier to make from barstock than from the castings.

[Jo]

Getting back to the eccentrics, they have a rib on the center, and the straps have a matching groove.  Wondering how you machined the groove and how close a fit is needed?

The eccentrics themselves look easier to make from barstock than from the castings.

I started on the eccentrics on 17th feb this year and moved onto the straps in march, all the techniques and jigs are in this thread 

Jo

[kvom]

I have finally paged through this entire thread.  Some good ideas here that hadn't occurred to me, and as well I saw some parts that allowed me to correct errors in modeling from the drawings.  One thing I saw that doesn't appear on the drawings is a bearing between the conrods and piston rods.

Some conclusions I've drawn from both your work and the modeling exercise.

1) I'd better not attempt this engine unless I'm willing to dedicate it as a sole project for the better part of a year, given my normal work rate.

2) Other than the cylinders, base, and pump,  I'd likely be more successful building the parts from bar stock than castings.  Or at least they would be easier since I have CNC capability.

I have modeled a fair majority of the parts, but the base, pump, and cylinders will require me to remove them from their virgin plastic wrapping for measurements.  I'm somewhat hesitant to do so since if I do decide not to make the engine I'd like to pass the kit on to someone who will.

[Jo]

The other thing as I was told by a friend is that while it took him 6 months to make the engine it took him another 6 months to fit the engine together and get it running. And I have three of them 

Jo

[Jo]

  Still assembling. I was told by a friend that it took him 6 months to fit his to get it working and he only made one 

Latest joy is getting the slide bars to allow the piston rods to run freely: Initially they were too tight and a bit more had to be filed off the cover so they run nice and smooth..

Jo