Recommendation needed for copper boiler repairs

This forum is dedicated to the Live Steam Hobbyist Community.

Moderators: cbrew, Harold_V

Burgtrains
Posts: 2
Joined: Wed Jun 05, 2019 10:44 pm

Recommendation needed for copper boiler repairs

Post by Burgtrains »

I have a new to me Little Engines 4-4-0 American coal fired steam locomotive that has a copper boiler in need of evaluation, repairs and testing. I am looking for recommendations for a who or what company would be able to do this for me,
The loco was built in the mid-1960's but does not appear to have seen much running time. Mechanically it is in excellent condition but upon filling the boiler with water and applying air pressure several tiny leaks were discovered. At about 80 lbs I noticed a small drip seeping out around a solder seam in the smoke box. And with a mirror inserted into the fire box I noticed several drops appearing under the crown plate at the points where several stay bolts were soldered in place. From an exterior inspection the copper appears to be in good condition (nothing obvious to me), but being fairly new to this scale of live steam I need an experienced copper boiler builder/service person to evaluate this. Of coarse I am hoping that these areas just need re-soldered but that remains to be seen.
I am familiar with silver soldering having worked in refrigeration for many years but I think I would probably have just enough knowledge on the subject to be dangerous so I need someone who knows copper boilers. So if anyone out there can help me or know of someone that can I would really appreciate it. Currently the boiler is located in southwestern Pennsylvania. It is not very large so I don't think shipping would be an issue. It weighs in at about 40 lbs and is about 20" long.
Thank you in advance for your help, Mark B
User avatar
Fender
Posts: 3084
Joined: Wed May 02, 2007 8:33 pm
Location: Chattanooga TN

Re: Recommendation needed for copper boiler repairs

Post by Fender »

Unfortunately, many LE-built copper boilers were assembled using “sil-fos” brazing rod, and when these boilers are fired with coal, the brazed joints are attacked by the sulfur in the combustion gases. This may be your problem. If the the boiler was brazed with a high-silver content solder, this is not an issue. I built a new boiler for another LE 4-4-0 that suffered from this fate, as such a condition is not repairable. I should also note that the current owner of Little Engines provides steel boilers that do not have this issue.
Marty Knox of Ridge Boiler in Michigan should be able to help evaluate this.
Dan Watson
Chattanooga, TN
User avatar
gwrdriver
Posts: 3439
Joined: Mon Jan 06, 2003 10:31 am
Location: Nashville Tennessee

Re: Recommendation needed for copper boiler repairs

Post by gwrdriver »

I agree with Dan. The age of your American suggests that it's boiler may be built using a phos-copper solder AND LE's cast bronze 1-pc firebox, which even in their best years were known to have solder-repelling inclusions and porosity. In fairness, far more of these firebox castings (also used on LE's 1" scale engines) were successful than weren't, otherwise they'd never have sold more than a few, but they weren't the Magic Bullet they were supposed to be and presented even skilled builders with challenges under the best of conditions.
As a former copper boiler builder it's my feeling that a 50+ year old leaky phoscopper-soldered cast firebox is going to be far more trouble (ie,$$$$) than it's worth to try to save. If it was mine (and I also have a LE American in need of a replacement for a badly made copper boiler) I would bite the bullet and have one made in steel.
However before reading it its Last Rites, I would try an old (very old) dodge to seal up a weepy boiler. Open the dome and push a handful of aged horse manure in the boiler, close it up and then steam it hard. The fiber in the manure will make it's way into seams and weeps and MAY (YMMV) seal the boiler. If not you only lost a little time and a handful of manure.
GWRdriver
Nashville TN
User avatar
Bill Shields
Posts: 10460
Joined: Fri Dec 21, 2007 4:57 am
Location: 39.367, -75.765
Contact:

Re: Recommendation needed for copper boiler repairs

Post by Bill Shields »

i am in the middle of building a copper replacement for just such a boiler...for a 3/4" 4-4-0 => trying to fix it is much more trouble than making a new one.
Too many things going on to bother listing them.
Marty_Knox
Posts: 1724
Joined: Thu Jan 09, 2003 6:50 pm
Location: Michigan, USA

Re: Recommendation needed for copper boiler repairs

Post by Marty_Knox »

I can't offer much hope for a successful repair. I recently tried to repair a LE 1" 0-6-0 with a cast firebox and Sil-Fos.
Twice I was able to seal where I was working but opened up other leaks. I am now making him a new steel boiler.
rkcarguy
Posts: 1730
Joined: Tue Aug 22, 2017 10:33 am
Location: Wa State

Re: Recommendation needed for copper boiler repairs

Post by rkcarguy »

I've done some "spot repairs" on boat heat exchangers using the TIG welder and a compatible filler with what the exchanger was originally put together with. Grind out around the leak with a Dremel first so you have clean metal. The TIG allows concentration of the heat(as long as you do it quickly) so it doesn't spread out and melt the filler out of other places and cause more leaks. If it's brazed with brazing rod, you may also have success doing the repair with silver solder at a lower temp that won't melt the brazing rod. Bronze castings can certainly be trouble makers, we used a lot of them in the exchangers and often I'd have to grind away the brazing and grind the inclusion out of the casting so it would take.
With the boilers age, I'd say it would probably be the best to make a new one as more leaks will probably pop up. Provided you have access to the leaky areas some repairs may get you another year or two.
James Powell
Posts: 504
Joined: Fri Oct 28, 2011 10:42 pm

Re: Recommendation needed for copper boiler repairs

Post by James Powell »

Another option is to use low silver content (high melting point) lead solder. Be aware, once you do that particular trick the boiler is nackered for trying again with silver, as they won't stick to each other, or in the vicinity of lead fumes. A lot depends on "how bad" it really is- things you don't think will work can at times work OK at least for a while...

Imagetubes cropped by Peach James, on Flickr

(due to be re-tubed at some point...they have crept about 1/4" forward...)

Ginger is another go-to for minor leaks in copper boilers.

I'll add- if you have ANY doubt as to the structural strength of the boiler, it is time to scrap it. But if it's a won't hold water problem, then trying to fix it is perfectly acceptable to me as a 3rd class Power Engineer. There is a serious difference between A & B... if it leaks, it doesn't really matter. If it fails structurally, then it could kill you, or others. If you don't know, ask the boiler inspector who is going to be certifying it as to their opinion. (at least, assuming the boiler inspector knows what a firetube boiler is...if it's a state (provincial) inspector, they may be even more clueless than you are...)

James
Burgtrains
Posts: 2
Joined: Wed Jun 05, 2019 10:44 pm

Re: Recommendation needed for copper boiler repairs

Post by Burgtrains »

Thanks to all six of you that have responded to my help request with amazing speed, knowledge from experience and insightful wisdom.

I have considered some of the last ditch repair methods that have been offered but I think that I must agree that in the highly unlikely event that the repairs are successful they would probably be followed by more leaks in the near future. And with the need to go through the involved process of removing and re-installing the boiler every time I would be best to do one installation with a new steel boiler.

This is not the conclusion that I of coarse was hoping for but it is the conclusion that I needed to come to. Thank you very much for helping me get there. A new steel boiler it will be. Mark B.
User avatar
Bill Shields
Posts: 10460
Joined: Fri Dec 21, 2007 4:57 am
Location: 39.367, -75.765
Contact:

Re: Recommendation needed for copper boiler repairs

Post by Bill Shields »

there are benefits to a copper boiler....
Too many things going on to bother listing them.
User avatar
Greg_Lewis
Posts: 3014
Joined: Wed Jan 15, 2003 2:44 pm
Location: Fresno, CA

Re: Recommendation needed for copper boiler repairs

Post by Greg_Lewis »

Bill Shields wrote: Tue Jul 30, 2019 1:33 pm there are benefits to a copper boiler....
But not to one's wallet! :lol:
Greg Lewis, Prop.
Eyeball Engineering — Home of the dull toolbit.
Our motto: "That looks about right."
Celebrating 35 years of turning perfectly good metal into bits of useless scrap.
OddDuck
Posts: 434
Joined: Fri Dec 16, 2011 1:00 am
Location: Somewhere south of Mt. Katahdin
Contact:

Re: Recommendation needed for copper boiler repairs

Post by OddDuck »

There s a product called "Boiler Weld", it's a sodium silicate based liquid that has colloidal material in it, it's designed to be poured into a boiler and seals from the inside out. It's available at plumbing supply places. It's about $11 a quart. My actual application is that I use it as a binder for sand cores for casting, I have never put it in a boiler. I guess it would have the same effect as the horse manure, without the organic sourcing. How long it would last I don't know either, but you wouldn't even have to remove the boiler from the loco to use it. Just a thought from someone who honestly doesn't have a lot of experience with boilers either, but it may help it last long enough that you can have a new boiler made before you stop using it.
"If you took the bones out they wouldn't be crunchy!" -Monty Python's Flying Circus
RET
Posts: 960
Joined: Wed Jun 07, 2006 8:36 am
Location: Toronto, Canada

Re: Recommendation needed for copper boiler repairs

Post by RET »

Hi Mark,

If you got it up to 80 psi. and just had a few small leaks, its worth trying a hydraulic pressure test. After all, you don't have much to lose.

Fill the boiler with water and use a hydraulic pump to add water. NEVER use air for a test like this, it is simply too dangerous! For our purposes, water is incompressible so there is very little stored energy. At this stage, don't worry about leaks as long as they are small (under steam, the small leaks will gradually go away). If you can pump up the pressure until you get to about 200 psi. without a catastrophic failure and only small leaks, the boiler should be usable.

Remember, for a new boiler, it must withstand a "proof" pressure of twice the working pressure without failing and for our "toys," the usual working pressure is between 90 and 100 psi. Also, when you get to the "proof" pressure, keep pumping as much as is required to hold that pressure for at least 5 minutes to be on the safe side.

Also to be safe, you should have a witness to observe the procedure to corroborate what you have done, especially if you are a novice.

Don't automatically assume the boiler is bad. As a matter of fact, it isn't a good idea to assume anything!

Best of luck.

Richard Trounce.
Post Reply