Challenger boiler by Stephen Bloy

John    There is no reason you couldn't use rivets instead of the screws Bob uses, Iv'e done this, you can make them from wire, or you could use escutcheon pines. You have to anneal the brass rivet first.       Stephen     (cTr....Choose the Right)

When I get lazy, or run out of screws, I use "rivets".  With brass pins, all you need to do is file the shank to less than one diameter, back the head up inside the boiler, and pound away.  No annealing required.

The problem is, you have to be absolutely sure you have good line up.  You do not want to drill them out multiple times.  And clean the brass before final assembly.

Thanks for the comments. I am gaining on the idea.  I will checkout Bartig and Thornsbough.   Really appreciate the help.  I never thought about building a boiler!!!! until bob2's discussions.  Wow.  Will keep you posted.

John

Stephen,

I want to build my first boiler.  My plumber gave me a 3 ft piece of 2" copper water pipe. Its pretty thick.  This will be my first try.  Would you comment on using the pipe.  bobr recommended where to purchase brass tubing and the wall measurement, but I cannot find his reply.  What would you recommend for tubing wall thickness?

John

.064 absolute max; .032 is optimum.  Too thick and you cannot easily solder stuff on.  A sink tail piece may do it - don't use one that has been in a sink.

My boiler is nearing completion - tonight I mount air tanks under the running boards.

Bob,

I remember in another thread you provided the link for the brass tubing.  Can you post it again for the OP?

Also, can you tell me where you get your fastners and screws (miniature ones).  I remember you said, I just can't remember the link.

Thanks

Post your finished boiler here, I can't wait to see it.

Sure. Tubing:

https://www.onlinemetals.com/m...tep=2&top_cat=79

Fasteners - MicroFasteners

http://www.microfasteners.com/

Photos - give me a week or so to get some stuff hanging on it.

Hi Bob,

Thanks for responding again.  Please post pix as encouragement.  Look forward to see the finished engine.

John

John      The tubing I used was also quite thick. The challenger boiler is a simple tapper, but for more complicated boilers, the thick material could be a problem. The soldering I did was accomplished using a torch, or flame, so Bob's advise would be well taken, unless your very confident soldering.      Stephen   (cTr...Choose the Right)

Thanks Stephen, 

I will order brass. Bob feel free to chime in.  What diameter brass tubing did you both use.  Will one diameter work or did you use more than one size.

John 

2 1/4" dia ought to do it.  Thickness as above.

THANKS BOB.

John

Hi Stephen,

I have been rereading  my earlier discussions on ogrforum.  In your posting with the challenger boiler you indicate that you used hard copper.  I have 3 ft of 2” plumbing copper pipe.   When you cut the sections did you try to cut the angle for the piece or just cut the section and file the angle needed? When you split your challenger parts did the diameter expand?  How did you make or purchase the brass rivets that surround the boiler sections?

I apologize for my ignorance.  You have been kind to respond to a neophyte metal modeler. 

John Douglas

There are ways to compute the angle of cut for a taper section, but they are x-y-z equations, and might be fun only for mathematicians.

I simply cut a piece a bit longer than I need, get the proper taper, then very carefully sneak up on the correct angle, using a table saw with a sanding disc, and a tri- square.

The taper section on a Challenger is fairly easy, since it is very gentle and quite long.  You want to make double sure that the taper is even on all sides and from both ends.

Copper tube is probably not optimum - I did one boiler in copper, 1/8" thick.  It was an interesting project, and the only time I attempted silver solder.  With 1/8" thickness, annealing the copper causes no real weakness.

Thank you Bob for the Sanding Disc on the table saw.  I will keep you and Stephen on my progress with the copper. I have your recommendation for the brass tubing which I will use in the future.

FYI.  I visited Bob Stevenson on May 13.  I spent 3 hours with him and walked away with many tips.  He told me how he acquired the Lobaugh, Pearse, etc dies and forms.  He has some spectacular Engines.  He took me thru his lost-wax casting and foundry work. He has used 3D printing to develop masters.  The operation is almost unbelievable.

I saw you responded to a thread about Bob's health. He was having problems with a pacemaker which was affecting lung capacity that limits his mobility.  His doc's scheduled an upgrade of some type the following week, about which he was not concerned.  He major concern is his wife.  She had been hospitalized for about 10 days while doc's try determine the reasons for her falling and to work on physical therapy. I am sure his spirits would be raised hearing from you and other o gaugers that appreciate his contribution to the hobby.

John  

Thanks.  I have been meaning to call.  Did not know his wife was having problems.