PMR #5 - as a fill in project

[b.lindsey]

Hi Dave, well I'm trying to get the boy to retire so we can think about starting up a model engine show with a southern ambiance ...lol.

Bill

[Dave Otto]

Sounds great, I would love to come and hang out with you guys.

Dave

[Tennessee Whiskey]

Y’all just keep rubbing it in    Maybe someday: heck, even DOG retired. Dave we would love to have you. Uh, on the l’tl popper Bill; let’s just say Bozo showed up and I’ll get to that this weekend. 

Cletus

[b.lindsey]

Well darn Cletus! Maybe if you offer Bozo free meals at the diner, he will stay away.

Bill

[b.lindsey]

A few little bits this morning. The piston is made from a piece of brass. Fortunately, I had made a .050" grooving bit for previous PMR engines no doubt so that helped (photo1). Then threaded the two eccentric rods and the piston rod as well as you can see in photo 2. Will see what this afternoon has to offer.

Bill

[b.lindsey]

One more quick picture. I made four 3-48 hex nuts and  one 5-40 hex nut, all from 3/16" hex stock. The 5-40 one locks the bottom of the piston rod to the crosshead. One of the 3-48 ones secured the piston to the piston rod and the other three fit on the valve and eccentric rods as shown.

Bill

[crueby]

 

[J.L.]

Hi Bill,

  as well...

Watching with interest as my crosshead is mounted to the piston rod in exactly the same way.

Great work.

John

[zeeprogrammer]

Y’all just keep rubbing it in 

Thanks! 

[Tennessee Whiskey]

All is looking great Bill. Those are right up there with Otto’s nuts. Will you be polishing your nuts    Zee; naw I ain’t gonna do that on Bill’s thread 

Cletus

[Dave Otto]

Nice nuts are very important.  Most folks put too steep of a chamfer on them, for models I like 20 degrees cut until it just goes full circle.

Looking good Bill!



Dave

[b.lindsey]

Thanks guys, sorry there isn't more to show yet but I'll get there. Cletus, how did you go about cutting that square for the valve mechanism? Two "v" grooves on the mating parts or other? Still head scratching on that one.

Bill

[Tennessee Whiskey]

Bill, I had a look back at my build ( Lord that was five years ago). I didn’t show that part, but, if my memory serves me well, I did do it with two V cuts. I think I might even have bought a small 45 degree cutter for it.

Cletus

[Jasonb]

You could just mount them at 45degrees and then use the corner of a regular milling cutter.

[bent]

Been scratching my head on that one too, Bill.  Have not yet cut chips on the #5, but have been fettling and painting castings, and slowly accumulating tools (like a long boring bar for the support frame) and thinking it through...

Debated buying/making a square broach for the holes, but that seems overkill.  The v-cutter will likely work simplest.