Chris's Slew-Crowd Engines

[cnr6400]

  Looking great Chris!

[crueby]

Looking great Chris!

Thanks Jeff,  I also got the lettering cnc-ed into the Marion cover plate this afternoon, pics in the morning, ran out of time to get them posted today before an event.

[crueby]

So far the Marion and Erie plates have had the lettering cnc-ificated into them, they still need final trimming and drilling which will be done on the normal mill. Not easy to get a decent picture of raised letters in fresh cut shiny brass, but here goes:


They will show up a lot better with a little time and/or paint. The Bucyrus plate is cutting now, that one is a much simpler diagonal rib pattern with no lettering.

[cnr6400]

 

[Kim]

That's some nice CNC carving work there, Chris!  Those plates will look even better with a little paint to make the lettering stand out. 

Kim

[Michael S.]

The lettering on the covers looks very good. Even though the motors aren't painted, I would have used a dark background for the lettering. I've done that before with my factory signs.

[crueby]

Thanks guys!  I haven't completely decided, but the engines will probably be painted grey, which would pick up the lettering well. If not painted overall, then at least coloring the background of the lettering would be a good way to go.

[bobh]

Some of that lettering must be tiny! What size cutter did you use? Looks great. Bob

[crueby]

Some of that lettering must be tiny! What size cutter did you use? Looks great. Bob

Hi Bob,


I used a sequence of  cutters to remove the bulk of the background then finish the details, first 7/64", then 1/16", finished at 1/32". There were a couple spots where the letters were close together where I  cut the gap with a teensy dental bur in a high speed handpiece. The 132 end mill gives the depth limit of 60 to 80 thou, since its flytes are short. With tool changes, it took about an hour for the Marion plate. Years ago when doing the steam shovel the same lettering was done with electro etching on thin brass that was inlaid into the cover, this engine is 2x the scale, just enough to mill the letters in. On that shovel it had Marion in large letters down the track supports, large enough that I hand milled the letters etch a sketch style.

[crueby]

The first three top covers were drilled around the perimeter for the mounting bolts, each one a different pattern according to how the originals were...

Then each clamped in place and used as a drill guide to drill the matching holes in the steam chest. At this point all the holes are tap size (2-56), after this step I took the covers to the drill press and opened them up to the clearance size.

Last up is the Thew cover. This one does not have any lettering on it, and notches in around the flanges on the cylinders. So far have the cover sized and the hole patterns sketched on and measured for drilling...

[vtsteam]

That lettering is pretty fancy stuff, Chris, especially that scale. 

Yay, the Thew.... 

[crueby]

That lettering is pretty fancy stuff, Chris, especially that scale. 

Yay, the Thew.... 

Can hear the chanting in the distance...   Thew!  Thew!  Thew!   

[crueby]

Got the Thew steam chest cover finished up, drilled/tapped the mounting holes, and did a small relief around the edge:

Then got the steam inlet pipe flanges turned/milled/drilled to shape, and loctited on the ends of some lengths of tubing...

While those are setting up, I'll get started on the valve rod glands, then the piston rod glands. I'll be using viton o-rings for the glands.

[cnr6400]

  Looking great Chris! I sure hope the shop elves don't come along and put the seats and upper tubes of those diner stools in the steam tubes.... Don't bolt the flanges down yet- you might see some elf acrobatics....

[crueby]

Looking great Chris! I sure hope the shop elves don't come along and put the seats and upper tubes of those diner stools in the steam tubes.... Don't bolt the flanges down yet- you might see some elf acrobatics....

I did see them reading a book about steam calliope building...