Pacific Vapor Engine from Morrison & Marvin Castings

[Dave Otto]

Hi Everyone

I got my cylinder back from my friend who honed it on his Sunnen hone; it came out beautifully and dead on the 1.750 diameter.


Continuing work on the piston the indexing head is rotated down to the horizontal position and indicated in.


The wristpin hole is now spotted, drilled and reamed.


The indexer is rotated back up and the wristpin retainer screw holes are drilled and tapped. I didn’t want to run the reamer across the holes so that is why I seem to be jumping back and forth.


Back in the lathe chucking lug has been cut off and the top of the piston finished; the threaded hole is for the post that works the piston trip ignitor.


A mandrill was turned that is a very light push fit on the ID of the piston skirt.


With the piston installed on the mandrill and the center in place the piston is turned to its final size.


Without disturbing the setup the ring grooves are cut using a Thinbit; the rings are .062”wide. Also but not shown I cut 3 .03” X .01” deep oil grooves in the skirt area. Being a vertical engine I’m hoping this may retain some of the oil and help keep it lubed.


I didn’t take any pictures of the construction but here is the wrist pin and square head set screws. Both the pin and screws have been case hardened.


And finally a couple shots of the completed piston with the hardware installed.



Thanks for checking in,
Dave

[vcutajar]

Nice work Dave.  I guess you are close to finishing the engine. What's left?

Vince

[smfr]

Looks good! Is it normal to hone the cylinder before cutting the wristpin hold and the ring grooves? I guess you just had to be careful not to leave any raised bits?

Simon

[Jasonb]

Grooves & hole are in the piston not the cylinder.

[Don1966]

Nice work Dave, I am curious about using square head sets crews to hold the wrist pin in place. Is this better and as secure as using E-Clips on the ends? Do they get loctite in place or just the jam nut? Since I have never built an IC engine just wondering how well this works.

Don

[Jasonb]

Common practice on the original engines of the period and thats whats being replicated, some also had extended screws so you could get at the heads if the skirt was long. Plus the pin won't wear the piston as the only movement is between pin and little end.

Also can't see how you could get an e-clip on the end of a pin, you may be able to use circlips on larger engines fitting into grooves in the piston or more common on our small engines is a bronze or teflon button on the pin ends to stop it rubbing the cylinder

[NickG]

Wow, it looks amazing - just like the real thing 

[Don1966]

Common practice on the original engines of the period and thats whats being replicated, some also had extended screws so you could get at the heads if the skirt was long. Plus the pin won't wear the piston as the only movement is between pin and little end.

Also can't see how you could get an e-clip on the end of a pin, you may be able to use circlips on larger engines fitting into grooves in the piston or more common on our small engines is a bronze or teflon button on the pin ends to stop it rubbing the cylinder

Thanks Jason, you have answered my question. I was thinking of the E-Clip been inside the piston sides not on the pin. But I can see if the piston is small it would not be feasible.

Don

[steamer]

I really like that indexing head Dave!

Nice work on the piston!....

Dave

[smfr]

Grooves & hole are in the piston not the cylinder.

Ooops, of course! I was confused by the proximity of that paragraph to the picture of the nicely finished piston underneath it!

Simon

[Dave Otto]

Thanks for the interest and kind words guys,

Vince; I have come a long way but there is still much work to do. After the piston and rod are finished it will be on to the intake side of the project. This will involve carving an intake valve chest from solid along with making the valve, valve chest cap, and bob weight.

I have 3 beautiful investment castings from Morrison and Marvin for the gas and air cocks; they will need to be machined and finished along with the piping to connect them to the engine

I have been doing some mods to the engine base and will detail those at a later date.

All the piston trip ignitor parts need to be made and the cylinder machined to accept them. This may get it running but then there is all the finish work, cooling system etc. to design and make.

I don’t work very fast but hoping to have it running later this year; completely finished only time will tell.

Simon; I may not have been very clear and the pictures didn’t show it. But the reason I waited for the cylinder is because I had left the piston a few thou oversized and wanted to know what size the cylinder finished at so the piston could be machined for the proper clearance.

I think Jason answered most of the other questions; thanks Jason.

I also got the rod finished last weekend and will try to get some pictures of its construction sometime this week.

Thanks again
Dave

[Dave Otto]

Thanks  Dave

The indexing head is a sweetheart; Kalamazoo I believe; it is very well made and the tilting feature makes it handy for some things, it is also very rigid. I picked it up used at our local used machinery dealer. I purchased a new tail stock for it from Kalamazoo through our local dealer and it was an absolute piece of junk from points Far East; it got sent back.

I started watching eBay and it wasn’t too long before I found a nice used one only this one was US made and matches the quality of the indexer.

This sad thing is Kalamazoo who used to make pretty darn good stuff now outsources at least some of their tooling to Asia.
I have one of their 2” X 48” belt sanders and it is a well-made tool; I guess going forward I would ask the country of origin before paying a premium price just for name sake.

Dave

[Tennessee Whiskey]

Dave, I have to say you are a Picasso in the machining department and an Ansel Adams in the photography of his work. Just beautiful. I'll be here till it runs, even if it's after the cows come home.

Yo Redneck,
Eric

[b.lindsey]

Beautiful work Dave!!  Thanks for these latest updates, I always look forward to seeing more on this engine.

Bill

[gbritnell]

Hi Dave,
I'm sorry I haven't been keeping up with your build. I just went back and started from the beginning. I must say it's great stuff. The photo coverage is first rate, well along with the build also. I sure miss my days in the shop with the CNC equipment but it looks like you're putting it to good use.
gbritnell