soldering

[sardine]

i have a copper hot water tank with a leak in the seam, it's a marine calorifier and worth repairing rather than weighing in, can anyone tell me the best way to do this, i have plumbing solder and active and normal flux, will this do the job ?

how di i de solder the seam and clean it out ?

 

[normspanners]

obviouslly drain it ! heat the join and blow out the old solder with an airline, a little at a time ps GOGGLES n GLOVES!! stick allum tape or something similar to save the solder sticking to the rest of the tank, or try some electrical desoldering ribbon that sucks the solder out .use active flux but wash it out inside and out after .
old leaded solder flows better and is stronger, I find, but frowned on for the lead content .

 

[piman]

Hello Sardine,

for a seam I wouldn't use plumbers solder (40% tin, 60% lead) but rather electrical with 60% tin and 40% lead , also called tinmans solder I think?

Alec

 

[jordan1]

I would opt for silver solder to be sure, or is that a little OTT.

 

[madkayaker]

How is it currently soldered?

 

[DrNik]

clean the area very thoroughly ensuring the area is dry, don't over-clean the area that way the solder wont go where you don't want it, to keep the solder in the joint,paint plumbers flux on the joint, blow torch the area gently just to get the flux working, using electrical solder is great as its got rosin flux inside the solder cleaning as it goes, not too much heat as you'll melt the solder further down the joint,you can lay some solder straight off the reel along the joint, flick the heat on and off, you'll see the solder ball up, keep flicking the heat on till it starts to flow, you can build up the soldr and as long as it flows around the edges and it flows across the joint all is good, wash off any flux, plumbers flux is corrosive, and test HAPPY DAYS

 

[the snooper]

use lead free solder, its now illegal to use leaded in pottable water systems if the leak are isnt dirty a simple heat up and some solder may cure it

 

[brightspark]

I would opt for silver solder to be sure, or is that a little OTT.

u cant use silver solder over something that has been soft soldered/ it wont take

 

[Tigman]

use lead free solder, its now illegal to use leaded in pottable water systems if the leak are isnt dirty a simple heat up and some solder may cure it

If its a hot water cylinder , He aint gonna drink the water from it any way so leaded solder is fine !

 

[the snooper]

If its a hot water cylinder , He aint gonna drink the water from it any way so leaded solder is fine !

wheather he will drink it or not, the fact its is still illegal to use and has been since 1987 however its upto him if he wants to use it

 

[madkayaker]

If its on a boat there is more regs as well. Might be worth asking on a boat type forum as well

 

[Tigman]

Sorry I stand corrected , it is illegal to use leaded solder on hot water systems so its a no no !