The Home Machinist!

Also check New England Small Tube Co. https://www.nesmalltube.com/

Hello My Friends
Here is a bit more concerning the plug valve. In this first photo it has had a swim in the acid pot and then a good zoom with the jewelers buffer. This is something I almost always do with these small parts. Metal finishing is an important part of good modeling. Now that our part is looking good it's time to drill and ream for the plug. It was center drilled, and then stepped out to 11/32". Then it was reamed with a .374" reamer. That's one thousandth under 3/8". Now it can be parted off. For the plug that will fit in this hole I will massage some .375" 303 stainless with #400 wet or dry sandpaper until it just fits. This will make a pretty good plug valve. And here is the start of the plug. You can see it has had the 1/8" square bit machined. Not its having the 3/16" diameter turned and this will now be threaded #10-40 Here the plug has been massaged until it's a good fit in the valve body, and now it's having the port cut. Once again the part was centered, then center drilled and stepped out to 7/32". Then the final cut through the plug was made with a brand new 1/4" end mill.

And here we have all our parts & pieces. The valve body on the left. The small round piece with the square hole in it will later be the end to the operating rod that will pass up through he cab floor. Then the plug. The 3/16" round part at the left end of the plug has been threaded #10-40. Then there is a shoulder that will accommodate an O ring. Then the body of the plug that has been massaged till it's a good slitting fit in the body. The hole has been made through the plug. The edges of the hole have been carefully chamfered and de burred, lest it gouge the inside of the main body. Then another shoulder for an O ring, and another 3/16" diameter bit to be threaded #10-40 after parting off. You always want to do everything you can before parting off. Here we have the completed plug and body. Notice the O rings on the ends of the plug. This will prevent any air from entering the valve, which will make the finest injector rather cranky. More to come
Jack

Very nice Jack. You must really have some good eyesight for all that little stuff lol

The 762 will be at the Riverside meet this weekend. It may not be running yet however.

Jim Kreider

Hello Jack and Jim,
again, very nice details . Like that construction of the water cook valve which avoids the risk of any air leaks
Looking forward to your Berkshire`s first steaming, good luck!

Best regards
asteamhead

Jim Kreider (seated) and Bob Chamberlain

Oooooh! Delicious! I realize people like the Big Boy and other huge engines, but I love a Berkshire! No engine is so perfectly proportioned.

No argument there.

Hello Jim,
Just looking fine - engine and driver
Congratulations!

Asteamhead