Thin heat shield for soldering

I want to solder firebox side stays but don't want to damage the existing solder on the tube ends less than 1/2" away. I had thought of using a bit of squashed down soldering blanket but wondered what other folks use.

Thanks,

Dave

I have found Cool Heat paste very effective on small assemblies.

MichaelG.

Is that stuff really called what I think it is!?!

N.

You can get Ceramic Paper

http://www.hightemperaturetextiles.com/needlemat-blanket-paper/refractory-and-ceramic-blanket-and-paper/ceramic-paper.html?gclid=CLWJmrrvzMcCFYYfwwodr6YH8w

I scrounged a bit from a local furnace repair company for doing a very similar job

I assume you have initially used a low temperature silver solder eg 42% with cadmium or 55% cadmium free.

The remelt temperature of both is higher than their original temperature. This is caused by the solder absorbing copper and changing its' composition.

Do a simple test.

Replicate 4 stays in a line. Braze them. Let them cool.

Now set up a parallel line of stays 1/2 inch apart.

Braze them with your low melting point silver solder. Use a suitable burner that will enable you to control the heat. Watching the flux will help you to avoid overheating. As soon as it goes clear your are at brazing temperature. Ensure you also cover the first line of joints with flux to protect them if you do remelt them

Alternatively attach a heat sink where rfequired. This could be a damp rag, a mole grip wrench or apply Pyrocool - a spray product available from Advanced Engineering Ltd Redhill (no connection other than we used to sell it - demand not meeting expectations).

Keith