The Home Machinist!

I have adequate water leg circulation space on my current boiler (6"diam) but it wouldn't hurt to relieve those inside corners of the backhead and throat sheet per Dave's practice.

For years I could wander in, pick through the bin, and buy "drops" (bar ends) in any steel from the #1 local tool&die supply for 10¢/lb. Ahh those were the days, but I learned that a bar end could be a piece of junk, with folds, inclusions, and hardness. Also sometimes the material couldn't be ident...

I don't do that, at least at that place. What I do is put a slight chamfer on the UNDERside of the lap, on the side I plan to feed solder to . . to give the solder an unobstructed entry point and draw it in. It also helps to leave the lap edge vertical on the solder feed-in side . . this essentially...

Understood. For a reference, an ID of .455" would put you at the lower limit of the "optimal" range but still workable. I'm using the formula for optimal flue diameter to length ratio D²=L/50-75, where D=tube ID, L=heated length, and 50-75 is a numerical range between which you will optimize the bal...

Re: Dockstader . . . I found Dockstader to be more of a "Proving" program than a design program. You first make a stab at designing the gear using whatever graphic capabilities you have, including mock-up building, and then test the results on Dockstader, adjusting to optimize the events. I first as...

datman wrote: ↑

Thu Feb 27, 2020 2:45 pm

gwrdriver: The flue length is approx 15 1/2".

Ian,
Using the formula for flue length to diameter, your flues will be optimized at .488" ID.

Ian, The 7/8" tubes should be adequate. What is your flue length, measure from inside head to head? Under the heading of "Making More Work for Myself" . . . I've considered trying concentric superheater elements, that is, where the supply line runs inside the return line. The elements would be relat...

What!!?? Someone built a locomotive without a DRO?

Then fillet until your heart is content. Make the fillets as large as your CAD software will allow. They need to be bigger than you think. Anthony, that's more like it! And I'm glad you brought this up . . . I was keeping my mouth shut, to avoid being seen as critical of something I've not done mys...

Marty, How you do it kind of depends upon what machine capacity you have, but in general I would begin by facing the mounting (to the frame) surface, followed by the valve face, and then locate the bore relative to those surfaces. I would finish the cylinder end faces by mounting the casting on a ch...

Conventional, . . not standard. "Conventional" would be a fabricated manifold from which pairs of superheater tubes (in and back) would be connected. There would be a different manifold/superheater tube arrangement for every different locomotive design. There would be many superheater assemblies whi...

My lathe came with a similar pump, although it's design causes it to leak out if left laying on it's side, making it more trouble (and mess) than it's worth. For pump oilers, no "nubbins" are needed . . . the hydraulic pressure of the oil will displace the ball, but occasionally quite a bit of press...