You will remember the nasty hole in the bottom of the radiator where PO (Previous Owner) had bodged fixing a mild steel pipe into the hole with a ton of lead. Thats not how I do things – my bodges are more elegant 🙂
So this is what I started with:
This is my plan… I have some old stock of brass bits and found some brass plate to patch the hole and a new brass pipe based / silver soldered in.
Step 1 – a darn good cleanup removing as much of the old lead as possible.
The brass tank needs to be very clean so that the lead based flux can adhere properly. I then paint on the lead flux and heat it up gently until it turns to a silver colour, a quick wipe reveals a very thin layer of lead now coating the bare brass.
The brass plate was trimmed to size and adjusted in shape to cater for ‘missing’ metal and then soldered into place. I had initially thought about brazing the plate – but realised that so much of this radiator is held together with lead (old school manufacturing) that the extreme heat from a welding torch would probably melt everything in sight!
Once the plate was in place, I cut the 32mm hole for the pipe, adjusted it into the right position and silver soldered that in place too. A quick clean up with a wooden paddle coated in tallow to smooth the solder and that was it job done. I then filled the radiator with water and left it overnight. This morning I am pleased to say there were no leaks.
Below is the patch and the pipe that will be tidied up a little and then painted along with the entire radiator…
Quite a difference to the first picture… and it is brass so it won’t rust again.