Boiler Silver Soldering – Not gone well.

[David DeavilleParticipant @daviddeaville66164]

My first attempt at making a boiler has not gone well, it leaks.

It’s the simple Polly boiler by Tubal Cain.

My gas torch wasn’t really powerful enough so even though it looks well soldered, it weeps water.

I now have a much bigger torch attached to a gas bottle and heated the whole thing to a dull orange hoping it would seal the leaks but it hasn’t.

Is it now scrap or is it possible to heat it all up again and full it apart and have another go with my much bigger torch ?

Thanks for any advice given.

[Martin KyteParticipant @martinkyte99762]

Well my first tip is if you reflow any soldered joint especially an assembly like a boiler is you must flux all joints first before reheating. It goes without saying that it also should have been through the pickle to clean it up.

 

[David DeavilleParticipant @daviddeaville66164]

Ok, i did pickle it all again before heating it up but didn’t think to re-flux the joints until it after I had heated it up and cooled it down again.

So it could be worth trying again with the added step of re-fluxing ?

[Andy StopfordParticipant @andystopford50521]

Definitely. Be very generous with the flux – slosh plenty on all the joints and heat it to dull red (in subdued light – not bright sunlight), and the solder should flow fine.

[bernard towersParticipant @bernardtowers37738]

If you mix your flux with meths it will not bubble as it does when mixed with water so therefore stays where you put it. give it a try I personally have no fluxes mixed with water.

[Bill PhinnParticipant @billphinn90025]

Yes, try again. Pickle, flux the joints, heat, and feed in more solder.

Can we take it your joints are conducive to good capillary flow?

[David DeavilleParticipant @daviddeaville66164]

I will try again then with lots of flux, the meths idea is a good one to.

Yes they are good joints so capillary flow is what i’m seeing.

[Speedy Builder5Participant @speedybuilder5]

Don’t forget – You should be using High Tenacity Flux such as TENACITY 5.  Ordinary silver solder flux will not be effective during a long heat process.

Bob

[Dave HalfordParticipant @davehalford22513]

Silver solder has a bad habit of requiring more heat to flow for a second time than the first time. Add fresh solder.

[bernard towersParticipant @bernardtowers37738]

Very true Dave the reason is that the bits that make it flow have burnt off

[Trevor Drabble 1Participant @trevordrabble1]

David , If it helps , I can supply you a small quantity of Tenacity flux for you to try.. Simply PM me your contact details to progress.

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