Re: Boilers

>Now, if we replace a boiler, how is it done?<
Buckets of cash!! Seriously, the manufacture of any boiler is a serious undertaking.
>Do we take the raw boiler, with firebox, smorkebox, and ship it to a boiler maker where they make an updated modern carbon copy of the original and hope when the new one arrives that all the holes, bolts, studs etc. all line up. How difficult is it to line-up the new boiler with all that fitted on to the old boiler?<
First, you will need to find a boiler manufacturer that will be willing to take on the job. You can find them in your area by looking in the yellow pages. If there aren't any in your area, then looking in the Thomas Register is the best place to look.
You should also make sure that the boiler manufacturer is licensed to apply the appropriate ASME stamps to the boiler when it is completed.
I don't think that it would be necessary to ship the old boiler to the manufacturer. Instead, what should be done is to prepare a set of what are called as-built drawings of the existing boiler. As-built drawings are detailed drawings drawn to scale that completely describe the physical dimensions of the items. It should be sufficient to supply these.
One complication that will occur is that you will need the physical envelope of the boiler to fit onto your existing frame as well as meeting current code requirements. This involves the setting of the boiler as well as all of the parts that are attached to the boiler.
In having the new boiler built, you should have a complete list of specifications. One of your important ones will be that the new boiler will match the existing setting on the frame. In addition, the specification should include various code and regulatory requirements. The other parts will involve being able to reassemble the fittings and appurtenances to the boiler.
This is a very long and involved process, and I'm afraid that I can't do it justice on a message board.
>Does the old boiler have any trade-in value?<
About two cents per pound as #2 scrap. However, if the boiler is of significance from an historical or technological standpoint, you may want to keep it for display.
>Who makes RR locomotive boilers?<
See above.