Up one level Neidrauer Adventures Photo Album and Blog » Building a Live Steam Locomotive - the Mikado Project » Section 13 - Boiler
Section 13 - Boiler
Completed. The boiler was fabricated by a machine shop in the hobby in 2003 and was part of the castings and prints when I purchased them from an individual.

 30-Apr-2012 Fixing a boiler leak.  I've drilled out the pinhole leak where the backhead meets the outer shell and will fill weld it next.  30-Apr-2012 A nasty surprise - a boiler leak before I've even used it!  The boiler was charged with 20 lbs of air from the compressor.  After chasing down all my plumbing leaks, I had trouble finding this one until it realized it was coming from the boiler.  24-Mar-10 Once again I have to thank the generosity of others to have the right tool when needed.  Here we are trimming the fire pan width to fit the actual boiler width.  Although the pan is clamped down to the table, a conventional right-hand cutting tool would pull the sheet metal up and chatter mercilessly. But I was given a left-hand spiral cutter, which pushes the metal away from the cutter, or onto the table in this case, resulting in a rock solid, noise free cut.  Here's one of those 'get around to it' tasks.  While we had the boiler upright, we needed to cut the dry pipe down a little.  As delivered there was only 1/16  24-Mar-10  One week later with a new tap wrench and new skip-tooth pipe tap, the holes are threaded quickly and easily. So easy in fact we had to check to see if the tap was actually cutting new threads.  It was! What a difference this setup made.  16-Mar-10 You can see both cleanout bosses here. I did not have a  16-Mar-10 After welding two more cleanout bosses on the back of the boiler, Bill tries to tap the 1/4  10-Mar-10 The boiler with four rings finished, next to the backhead band.  The smokebox mounting ring doubles as the jacketing mount band.  10-Mar-10 We rolled the boiler band mounts, slipped them over the boiler and used bailing wire ('Ford wire' said Bill) to squeeze it down for tack welding.  We are still using 1  3-Mar-10 Tacking spacers for the boiler band mounting rings on the shell.  24-Feb-10 We decided to weld the boiler mounting bracket to the bottom of the boiler instead of bolting it like the print calls for.  I didn't want to grind all the uneven mud ring weld beads flat, or try to hand drill and tap through the weld into the mud ring.  17-Feb-10 After considerable effort to remove the smokebox from the boiler thanks to the now Press Fit boiler band (instead of a slip fit), we prepare to finish weld the rear boiler mounting bracket and the boiler bands.  Match drilling the rear boiler support bracket. We had to remove the wood blocking holding the boiler up to install the support bracket. Using machinists jacks inside the firebox, we hold the rear of the boiler up, and using a level inside the firebox on the crownsheet, set the crownsheet level front to back and left to right. The angle bracket was tack welded to the bottom of the boiler before drilling the holes.  Using a 1/2  Here's one of the blueprint mysteries: How do you bend a 3/4  13-Feb-2010 Machining the rear boiler support bracket plate.  After waiting 5 weeks from my metal supplier, I finally have some stock to work from.  First we laided out and drilled the holes with the vice square on the table. Next we installed the swivel base on the vice to cut the angled sides.  This was the first time the swivel base has been used, I had to clean the protective wax off it from when it was shipped.  10-Feb-10 The rear boiler mounting bracket has been fabricated, temporaily installed and the angle bracket clamped in place to be tack welded.  6-Feb-10 The boiler temporaily installed on the chassis, front smokebox mounting ring welded to the boiler.  Strips of metal used to fill the gaps between the out-of-round boiler and very round smokebox and mounting ring. You can tell I'm not an experienced welder--someone better would have run a bead down the boiler, then welded from the ring edge to the previous bead to bridge the gap. I'll remember that for next time!  6-Feb-10 The first mounting of the boiler on the frame. The orange strap is keeping the boiler tight against the smokebox until I can weld the mounting ring. The back of the boiler is temporarily held up with wooden blocks while I wait for my metal order to come in.  We spent some time fussing with boiler position on the frame. We didn't find much of a reference for centering it left to right.  We ended up trusting the turret bushing on the backhead to be centered, lining it up with the drawbar kingpin hole. 

We had leveled the stand before mounting the boiler, so using a small 6  Previously, the mud ring on the bottom of the boiler was ground a little bit flatter to better fit the firepan, and the front of the boiler was ground to fit the smokebox ring and the light coating of paint removed for welding.

Using the shop crane and some straps, the boiler is positioned on the frame for the first time.  My buddy Al stopped by and gave Bill and I a hand. Here we are mounting the smokebox to the cylinder saddle in preparation for the boiler.  Saturday 6-Feb-10. Another wet, snowy day outside means no track work, we retreat to the shop instead! Bill and I drill and tap for eight 10-32 screws to hold the smokebox onto the boiler. This was a hand drill/hand tap operation.  3-Feb-10 The smokebox to boiler mounting band has been rolled, sized and welded together.  We have had to adapt the blueprint plans to the boiler since the boiler is both not round and is undersize from the prints. We will use a wide 1-1/2  Bill test fits the band. We are getting close to the right diameter, looks like we need to cut a little more off the ends.  This is not the final position of the band.  3-Feb-10 My poor aged pinch roller suffers abuse when I roll the 3/16  13-Jan-2010. Kind of an odd perspective here. The boiler is vertical standing on the floor and the smokebox is sitting on top of it. You can see how the smokebox and boiler do not quite line up since the boiler is not round.  20-Jan-2010. Filing the factory bevel on the end of the boiler. The bevel is put on the pipe at the time of manufacture so the welders (when joining it to another pipe) do not have to field-grind the pipe for welding. Unfortunately for me, a bevel-edge does not make a good mating surface for the smokebox, so we will have to grind it down.  I would chuck it up in the big lathe except 1) the firebox won't clear the ways, and 2) the steam supply line would get in the way.  A look at the bevel edge that has to go. Another reason we need a flat surface is the boiler is not actually round, unlike the smokebox. The 12  Bill takes a large file to see how much of the factory welding bevel we will have to take off to make the smokebox fit on the end. Conclusion: A lot. Time to get the angle grinder out.  End view or smokebox view of the new boiler. The perspective is a bit strange since the 50  Bottom view of the big firebox.  Inside the firebox you can see the copper ends of the flue pipes, called flues, these will allow the coal smoke to pass through the boiler to the smokebox, then out the smokestack. 18-July-2002  View of the finished boiler sitting in my garage leaning against the wall.  It is  The firebox before installation.  The firebox with a view of the crownsheet stay bars.  The boiler under construction