cylinder block.

[Fender]

Daves1459, you said, “The cylinder shown has a A36 saddle section, a 12L14 cylinder, and aluminum bronze valve seat.”. 12L14 steel and (especially) Al bronze can be very challenging to silver solder. Could you elaborate on your technique for silver brazing these materials?

[SF2900]

Out west we generally attribute the built up cylinder block to Ed Yungling. Bob Reedy acknowledges this in his LS magazine build articles. But as in everything, it had been done before just not as prevalent. I'd seen pictures of them in early LS magazines and ME from way back. It's funny because a full size cast locomotive cylinder block looks just like a built up block. The amount of outside coring needed to reduce weight, reduced them to their absolute bare necessities in terms of mass. It's easy to see where the built up idea came from just by looking at a full size cylinder block.

Ed's son, Don, shows his built up GS1 block in this post as does SF2900 which I believe Ed is involved with.

viewtopic.php?f=45&t=98257&start=24p#p304218

Ken-

Yes, Ed is heavily involved with my build and we are following his methods for the cylinder block construction. The pictures in post #73 in Don's GS-1 thread are pics of my block. But from what Ed has told me, the construction methods and techniques used in the fabrication of Don's GS-1 cylinder block and my block are nearly identical. The rivet-counter side of me would have liked to have used a cast block, but the practical side won out on this one due to the simplicity of this construction method when comparing it to creating cast iron block from scratch.
- Ward

[daves1459]

Daves1459, you said, “The cylinder shown has a A36 saddle section, a 12L14 cylinder, and aluminum bronze valve seat.”. 12L14 steel and (especially) Al bronze can be very challenging to silver solder. Could you elaborate on your technique for silver brazing these materials?

I have not had any particular problem silver soldering 12L14. I make sure the parts to be soldered are brilliantly clean and I use the lowest melting temperature and freest flowing "safety" solder I can readily get. In my case "Safety-Silv 56" which is a good solder that flows easily and fillets well. I use the standard white flux and apply it liberally. After applying the flux I let it dry overnight so that the water solvent evaporates. By letting the water evaporate when heated the boiling is eliminated allowing the flux to better stay in and cleanse the joint. If the parts to be soldered are small I often puts pieces of solder under the flux AKA Kozo's technique. With the water absent the flux melts into a viscus goo and holds the solder pieces in place in the joint. Lastly is the heating process. I bring everything related to the joint to be soldered up to very dull red temperature before putting the torch briefly on the joint to flow the solder. In the case of the cylinder assembly pictured the whole assembly was brought up to dull red then the solder touched into the joint. It takes a lot of heat on an assembly that large. By the way it is desirable to bring the parts up to temperature as quick as practical. Except for smaller assemblies an oxy-acetylene welding torch is to small. A rose bud heating tip works that spreads higher heat much better. Keep the torch moving and don't burn the flux.

Aluminum bronze can be very difficult to silver solder, some can not be soldered. Any alloy with 10% or more aluminum will be a problem. I use industrial grade #642 that has 7% aluminum and 90% copper. It is not the hardest or best wearing aluminum bronze. But, it wears well with cast iron valves. It wears better than the usual silicon and phosphor bronzes. Avoid SAE660 bronze for any silver soldering. The soldering process is same as above except I used Easy-Flo 45 solder. Easy-flo 45 is the lowest melting temperature, most fluid, best penetrating silver solder commonly available. But be careful, it has cadmium in it and can be nasty even fatal stuff. Have a fan on and windows open for lots of ventilation. With that said I only use it for small parts of critical nature. In the case of the cylinder pictured the entire assembly was silver soldered with Safety-Silv 56 except the valve plate where Easy-flo 45 was used. I suppose Safety-Silv 56 could have ben used for the valve plate too, but wanted to use the least risky process for such a large complex assembly.

I hope I have adequately answered your question, Dave

[Fender]

Daves, Thanks for the detailed description. Is the reason for avoiding SAE 660 (AKA C932) because of its lead content?

[daves1459]

Daves, Thanks for the detailed description. Is the reason for avoiding SAE 660 (AKA C932) because of its lead content?

Dan,

Some suppliers rate SAE 660 as easy to solder and braze, others say poor to fair. I'm in the poor to fair camp. I'm not sure what the problem is, whether it is the lead or zinc. Zinc melts a couple hundred degrees F higher than lead but gasses around 900 F. I don't know about lead. Or it could be the manufacturing process. The SAE 660 I'm used to comes from Bunting as continuous cast as opposed to wrought like all the other bronzes I've seen. Any way, my experience is the silver solder is difficult to get to wet the SAE 660 surface and/or beads up on it.

Dave

[Greg_Lewis]

When I've silver soldered large assemblies I've stacked up some fire brick to make a little hutch and then used a propane weed burner for heat. It can take some time for everything to get up to temp. It's a bit of a makeshift furnace but it works.

[kenrinc]

The rivet-counter side of me would have liked to have used a cast block, but the practical side won out on this one due to the simplicity of this construction method when comparing it to creating cast iron block from scratch.
- Ward

Everyone who has seen my block asks me who I got the casting from. Completely fabricated. It can easily be made to look exactly like a casting. $.02

Ken-

[Cary Stewart]

The late Bruce Ward fabricated his cylinder blocks and saddles(?) from brass with bearing bronze bore liners. They were piston valves with Walsherts (spelling) motion. One of the problems that he was working on was the linkages to make one set go forward while the other went backwards. His loco was a 1.6" 0-4-0 + 0-4-0 Garrett. It went to the Huston, TX area. I wonder if it survived the hurricane last year?
Cary

[Cary Stewart]

Oh ya. Bruce used silver solder. It all came out fine. He had tested both engines on steam using the LALS steam plant boiler output.
Cary

[LSGOD]

The Pennsylvania RR did some built up cylinder blocks from welded steel and some drivers. All of my locomotives except for a 15" gauge shay have welded steel cylinder blocks with brass liners .The cylinders have hydraulic cylinder teflon rings. The valves have automatic transmission seal rings.
My cab forward has run over 40 years without cylinder problems and my son Don's SP GS-1 has run over 20 years. I used double extra heavy pipe for the cylinders. ED