Pennsylvania A3 Switcher (Kozo)

[Kim]

The next part for the valve is the stem.  This was made from 3/16” 303 stainless steel rod.  I turned the 30^o tapered point first.  Actually, I did that twice.  Once with the compound set at 30^o, then the second time with it set at 15^o to provide an included angle of 30^o, which is correct! 
Next, I turned the stepped diameters and threaded a portion of the stem 6-32.


Finally, I used the grooving tool to take the top end down to 3/32” to fit into the valve wheel made yesterday, then parted it off.


Here are the two parts for the blower valve stem.  I did do a little more clean-up work on the hand wheel.  I think it looks better. Not ideal, but better than yesterday!


Here’s what it looks like after silver soldering the parts together.  Not too bad!


Next up will be the valve body.
Kim

[tzkelley]

Looks great, Kim!

[cnr6400]

 

[Kim]

Thanks Doug and Jeff! 
Kim

[wagnmkr]

Very nice hand wheel Kim. The detail you are putting into this project is great!

    Tom

[Kim]

Thank you, Tom 

Kim

[Kim]

Continuing on with the parts for the blower valve, I made the blower valve body and a steam pass-through plug.  These were both made from 5/16” hex bar stock.

The plug was just like other plugs, so no pics there.  The blower valve body is a lot like those pass-through plugs, but just enough different that I took a few detail pics of that part being made.

It begins as a very standard plug, but the center hole passes all the way through the plug.  I made the basic shape, threaded it 1/4"-32, and then parted it off.


Changing to a 1/4" round collet, I held the plug by the threaded part and shaped the other end.  Then I drilled it about two-thirds of the way through with a #37 drill.  This will make the valve seat for the tapered end of the valve stem.  Then I tapped the end 6-32 to match the threads on the valve stem.


Now over to the mill to drill the cross hole.  When the valve is open, this will allow steam to go through to the blower pipe.  I started the hole with a 1/16” end mill, but for clearance reasons, switched to a 1/16” jobber length drill to finish the hole all the way through.


Here are the two parts made today.  On the left is the valve body, and on the right, is the plug.


I couldn’t resist screwing the valve stem into the valve body to see how it would look.  It looked pretty cool to me!


The last piece of the blower apparatus will be some donuts and a short tube to connect the steam input bush to the blower bush on the boiler.

Thanks for looking in!
Kim

[crueby]

Super clean parts!   

[cnr6400]

 

[Prowler901]

Great looking parts, Kim!  There are lot's of intricate little parts in the cab. 

Todd

[Kim]

Thanks, Chris, Jeff, and Todd!   

... There are lot's of intricate little parts in the cab.

No kidding!  And there's still more of them to go.  After the blower, I've got, the blow-down valve, the sheet metal for the cab itself, the air tank (which is where the battery for the lights will be hidden), and lots of plumbing work.  And I mean a LOT of plumbing.  But I am getting close, which is very exciting!

Kim 

[Baltic]

Amazing work Kim, well done 

[Kim]

Thanks Gary! 
Kim

[RReid]

I couldn’t resist screwing the valve stem into the valve body to see how it would look.  It looked pretty cool to me!

I agree! Enjoy the donuts (where's the coffee emoji?).  

[Kim]

For one reason or another, I’ve fallen a couple of days behind in my updates. But I’m going to try and catch up now.

So, on Monday, I finished up the blower valve pipe work.

Here are the donuts I made along with the short length of 1/8” OD copper tubing that will connect them.  Note that these donuts have that groove on the inside so that the steam can travel through the holes in the plug, around that groove, and into the tube.  That’s the only tricky thing about the donuts is that inside groove.  But it’s the same as the last couple of these I made.


Silver soldering the tube onto the donuts was a little problematic.  The silver solder kept wanting to plug the end of that tiny 1/8” tube.  It took me three tries on one end to get it soldered without blocking the tube.  And it’s not like you can drill it out after it’s soldered because there’s no way to get a drill in that tiny opening.  So I had to unsolder it, clean up the part, open up the hole, and try again.  My last try, the one that worked (which I guess is why it was my last try) was to put a bit of a chamfer on the inside of the hole in the copper tube to make it easier to work a bit of that correction fluid type anti-solder solution into the hole.  That seemed to keep the hole open through the soldering.  I had tried the fluid on the second try, but without opening up the hole in the tube, I don’t think I got a meaningful amount of the stuff in the place I wanted it to go.  Anyway, I worked it out in the end.


And here it is in place on the backhead of the boiler. The plug toward the top of the backhead is the steam inlet, and the slightly lower one feeds the long tube through the boiler to the steam box where the blower pipe is attached.  It seems to work because I can feel air stream out the top of the smoke stack when I open that valve!  Pretty cool!


So that’s it for the blower valve.
Kim