Chris's Slew-Crowd Engines

[crueby]

Got all eight cylinders profiled on the outside, then started drilling/boring the holes. I am taking these out just partway, will finish boring the cylinders to final size after the steam chests are silver soldered on. That will clean off any scale left from the soldering, plus ensure that the heating did not distort anything. Not sure if thats really needed, but its the way I've been doing them for a while now and it works out very well. I also take a final light cut on the end and drill the hole patterns for the mounting bolts in the same chucking, ensuring that everything is concentric. The outer ends will be the ends against the crosshead guide on the engine.

Here is the first one being bored out:

On the final pair, which happen to be the longest cylinders, I had to switch to a larger boring bar partway through since the 3/8" one I started with started ringing when extended out from the tool holder that far - these last ones are just under 2" long, and I wanted to bore just past that. Learned on previous projects that I could only extend the boring bars out so far for each diameter bar before it would start to vibrate and ring, giving a rough surface. I am only drilling/boring slightly past the end of where the cylinder itself is, to leave the extra used to hold in the chuck as a usable piece after it is cut off.

I have one more to bore out, then will start making the steam chest bases to solder on to the cylinders to complete the 'casting'. Got some ideas on how to cut the flat on the bases to fit the cylinders... 

[samc88]

Interesting project Chris, looking forward to seeing them all come together

[crueby]

The shop elves inspecting their new beer steins... HEY!  They are cylinders you guys! Clean that back out! 

[Kim]

That's a great start, Chris!  All 8 cylinders cut to shape.  Not too shabby for a weekend's work! 

Kim

[crueby]

That's a great start, Chris!  All 8 cylinders cut to shape.  Not too shabby for a weekend's work! 

Kim

Thanks Kim! I do love spinning brass in the lathe, cuts so nice, no hot chips or curls. Still lots to do on the cylinders, far from done though.

[cnr6400]

  You must have forgotten to take the battery out of their forklift I think, otherwise the shop elves couldn't lift them to have a glug.  (Elfensteiner stubbies are a lot more portable I guess)

[steam guy willy]

Hi  "C"  another interesting project going forwards  !! 
cheers
Willy

[crueby]

You must have forgotten to take the battery out of their forklift I think, otherwise the shop elves couldn't lift them to have a glug.  (Elfensteiner stubbies are a lot more portable I guess)

I did take the batteries. Learned some new language when they figured out they couldn't lift them...  Then they discovered the coil of air line on the shelf makes nice straws...   

[crueby]

Hi  "C"  another interesting project going forwards  !! 
cheers
Willy

Thanks Willy! 

[Brian U]

These will be impressive builds ! 

[crueby]

Thanks Brian!

[crueby]

Got a start on the first sets of steam chest bases. These will have a curved face on one side to closely fit the cylinder, flat face on the other for the valve plate. Trying a different method to make them this time. Started with milling out blanks for the Marion and Erie cylinders since they have the largest diameters/lengths - some of the jigs will be able to be cut down for the slightly smaller ones. The blanks are 3/8" long to allow for the holding jig, which is simply two steel plates drilled for holes out in the 3/8" extra. Though I think the elves are eyeing it for a new vault to store their beer money in...

It was centered up in the 4-jaw on the lathe, and the jaws tightened down. Going to use a 1/2" boring bar to handle the long (2") interrupted cuts.

The steel side plates are slightly longer than the brass blanks, so I can cut all the way through the brass without hitting the chuck. Here it is after lots of passes to get it out to the diameter of the cylinder center section:

Before starting I had also made this little go/no-go gauge with steps that match the two cylinder sizes, later on I'll turn it down farther for the other two cylinder sets. In the picture you can see where the screw holes from the jig came through into the bore - that is in the extra 3/8" length and will be trimmed off later.

Here is the gauge after the bore just got out to size:

While its still in the chuck, I will bore the outer end down past the extra length and also the thickness/diameter of the cylinder end flange. The same trimming will need to be done at the other end of the pieces, but re-centering the jig/parts will be tricky, so I will likely hold the assembly on an expanding arbor to do the other end. So far so good, next time I'll find out how well it all comes out!  The bases are wider than needed, they will be trimmed down the sides to final size - they needed to be wide enough for the steel plates not to get bored through, though the ends will get cut into a little when doing the flange cuts.

[vtsteam]

I like that method a lot, Chris. Looks really good, and very efficient.

Chris, as a foundry work person question, were those engines originally made from a single casting of both cylinders and the valve box together?

[crueby]

I like that method a lot, Chris. Looks really good, and very efficient.

Chris, as a foundry work person question, were those engines originally made from a single casting of both cylinders and the valve box together?

Yes, they cast the cylinders and steam chest in one pice, the main frame with crosshead guides as another. These engines were pretty compact, even the larger ones were often  less than about 3 feet wide and 4.5 feet long overall, some 2x3 foot on smaller shovels.

[bent]

This is an interesting project.  How do you keep the different parts set straight, do you have some bins set aside or are you marking them as you go?