Building Kozo's New Shay locomotive

[b.lindsey]

It sure does Chris, what with the daily growth spurts   And a fine looking boiler it will be too!!

Bill

[ths]

It's definitely going to be a boiler when it grows up. Hugh.

[crueby]

Got the conical section soldered on - looks like I am hitting the limit on the torches I have (handheld MAPP gas) - with this much mass and surface area it is wicking away the heat almost as fast as I can apply it. Got some missed spots that need another pass, most of it took - just.

I am looking around at other torches, anyone have any suggestions for an economical way to go? Has to be available in the US (seen some nice ones that are common in UK/Europe but not here). Prefer to go with something that could hook up to a standard 20lb propane tank, since I have one of those (current model threads on it, they changed them a few years back). I've seen some that are intended for roofing work that look like they put out a lot of BTU's, could heat a large area up while I could zero in with the mapp gas torch for the joint being soldered. Anyone use that type? Better way to go??

[Rustkolector]

Crueby,
Have had the same silver brazing problems as you with large pieces. One solution is oxy-acetylene. Some boiler builders, however, say it is a dirty flame and prefer the cleaner burning propane turbo torches for boiler work. With O-A I sometimes got small hot spots which aren't good when brazing brass. Propane is not as hot as O-A, but will do the job if you plan ahead. I use a Goss AP-1 handle and their turbo tips, like the BP-17PM. There is no BTU rating for this tip but the hotter flame of the turbo tips provide a lot of heat. Look on Ebay. The larger Goss brush tips supply up to 300,000 BTU/hr, but that amount of heat going everywhere sometimes makes it difficult to get close with your brazing torch. Instead, to make up for heat loss I have found insulating brick hearths used with insulation blanket material help considerably. I have also used an old electric hot plate which kept a good sized project of .125", .188", and .250" brass plate at about 700F which allowed the torch to be used quite effectively, and the actual brazing time reduced. An assistant with a second torch moving ahead of you will also work well if he is around when you need him.

With the old Mapp gas no longer available, I don't think the marginal increase in heat of the current MAPP Pro over propane is worth the extra cost. With the Goss or similar turbo propane torches and a little planning, you should be able to silver braze most any small boiler with ease using straight propane.

Jeff

[crueby]

Rustkolector:  I had noticed the change in the labels from MAPP to MapPro, but was not aware of what the change was. Did they change the mix for some reason?? Also noticed that they are putting 14.5 ounces in rather than 16 like before. Was this an environmental change, or did the bean-counters get thier grubby paws in there again?

The hot plate idea is an interesting one too. I assume you were using the torch well above the hotplate itself?

[crueby]

As I mentioned earlier, while waiting for the bigger torch for the main boiler shell assembly, I went ahead with the firetube assembly - three firetubes and the firebox. First photo shows the tubes soldered into the front firebox plate - up at the top out of the shot I had the front endcap slid into place on the tubes to hold them in alignment.

Second shot shows that assembly screwed into place on the firebox, and then soldered up. The front endcap is still there at the left end, that is not soldered on yet, just using it to hold/support that end of the tubes. It gets soldered in place last, since it has to go on from the outside of the outer shell.

The third photo show the back firebox plate being checked for fit - spent some time tweaking the shell and tuning with a file to get a tight fit. By shining a flashlight from inside, I could see any gaps and where the two pieces were touching - file down the touches till the gaps go away. On the first plate I'd just hold it up to the window, but on the second needed the flashlight to get into the corners.

Last shot shows the plate fitted and screwed into place, ready for soldering up.

By then, was getting a little tired, and got to the 'put down the tools and go do something else before you do something stupid' point. Probably will solder this up tomorrow, or may wait for the other torch - getting a lot of metal in one place now, that firebox shell is a lot thicker than the outer boiler shell, and the front end took a while to heat up.

After the firebox and outer shell are all soldered up, the next step will be to put the two assemblies together and fit/solder on the boiler backplate. Not bad progress lately - happy with how it is going so far!

[b.lindsey]

Can hardly keep up with your progress Chris!  It all looking really nice though!

Bill

[Rustkolector]

Crueby,
They stopped making the original Mapp gas sometime before 2009 for whatever reasons. I believe it is still available in Europe, but not in the US. The Mapp Pro gas is only about 170F hotter than propane when using air, but a lot hotter than propane when using oxygen.

The high BTU brush type torch can be a benefit if used as a second torch, but the insulating brick hearth and blankets do almost as well because most of the heat going in is reflected back into the project. The hot plate or open gas burner also works well. It can be used for preheating (heat and remove) or maintaining heat leaving it right on the burner. 

Jeff

[crueby]

Can hardly keep up with your progress Chris!  It all looking really nice though!

Bill

Hey Bill, hope you dont go into Loco Build withdrawal this week, been outside doing yard/leaf cleanup on the last nice days for a while - got a week of rain and (ick) snow moving into upstate NY so will be back at it soon!   

[b.lindsey]

I'll try not to...I'm not quite that bad off yet, but still enjoying your build whenever you can post Enjoy those last few days of good weather...I'll still be here when you go back inside.

Bill

[Roger B]

Still following along with interest  Those are some big bits of copper to heat up 

[crueby]

Still following along with interest  Those are some big bits of copper to heat up 

Sure are - amazing how quick they can wick away the heat from a small torch.

[crueby]

Well, gotta love having the right tools for the job. Got the bigger torch today (Sievert), and it really does the job. I probably could have gone for a slightly smaller nozzle, but this one had the full kit (regulator, hose, torch, end) at a reasonable price - it is one of what they call a roofers detail torch. I used it to heat up the whole assembly close to soldering temperature - got there pretty quick - then turned that one off and used the smaller torch to put the final heat on the joints. These types of torches are most definitely an outside tool - no way would you want to do this indoors (unless you have a MUCH bigger shop than mine, I guess!). Worked out great - redid the couple joints on the outer shell that I could not finish before, and also soldered up the backplate on the firebox (no new pictures, looks just like before just with solder). The pieces pass the light and water leak tests, looks like full coverage - best I can do till static pressure testing can be done. The pieces are soaking in pickle again right now, will get them cleaned up good and ready for fitting together next session.

Thanks to all those who gave me advice on torches and techniques in the different forums!

[crueby]

Okay, back at the boiler fabrication - got the backplate (photo 1) and front plate fitted (photo 2). It is getting heavy - current boiler assembly is just under 10 pounds now.

With the end plates fitted, and the back plate held in with screws (am using steel socket heads for temporary holding now, since they will be put in and out a number of times before switching to brass screws for final soldering), next step is to fit the bottom plates. These plates fill the gap between the bottom edges of the firebox and the outer shell. They are made out of the same thicker 3mm copper as the firebox shell, and will be made in four sections, one per side, both for ease of making and to allow the firebox to be removed to solder the bottom plates to the outer shell first.
I started by making a cardboard template of the forward plate, then transfered that outline to the copper sheet to cut out the blank. (photo 3)

After a lot of finnicky fettling, forming, feeling, fastidious fitting, and fussy fine flipping filing, got it shaped down to a close fit (photo 4). It will have a temporary screw to hold it in place while making the rest and soldering them in (needed since it is soldered to the outer shell with the firebox removed). Probably going to be a few days to make the rest - can only take so much time with that many F words!

When not working the metal side, have also gotten a start on the display base. I picked up some nice looking nickel rails, and started making a length of wooden trestle bridge for it to sit on (just sitting square on a flat base seemed too boring). The bridge section is curved to show off the articulation between the engine and the wheels, and is also tilted slightly into the curve - will show off the engine side nicely that way. Got it all glued and bolted together (since it will be holding about 55 pounds of train, I dont trust glue only - all the main joints in the uprights are also bolted). Will give it a thin wash coat of black to make it look like old creosoted timber, and mount it on a baseboard. Couple pictures of it in photos 5 and 6 (dont have the last of the diagonal bracing in yet in these photos).

[Tennessee Whiskey]

Crueby,  been following along quietly and enjoying it all.  I think as fast as you are going,  if you and Jo hook up,  y'all could build a Trans Atlantic railroad  :lolb

E