'Welding' lead - how?

[Robigus]

I have to make a simple lead flashing to go around a flue on a shed roof.
Something like this:

I bought a roll of lead, chopped a bit off, folded it in half, held it in a vice and heated the edges. These sealed up beautifully and I thought what an easy job this was.

Now though when I repeat it either the two leads won't fuse or it all melts away. Videos on YouTube seem to do it with out using fluxes or filler - what is the trick?

 

[multi power]

does it need to be clean, like soldering i wonder? bakers fluid for cleaning

 

[Anonymous...]

Seem to recall they used tallow as a flux , could be wrong though !

 

[Y Fan Wen]

http://www.wikihow.com/Weld-Lead

 

[Spuddler]

You do know you can buy those already done

 

[Robigus]

You do know you can buy those already done

I know, that's where I got the picture
A whole roll of new lead was about an eighth of the price of a ready made one - and I wanted to have a go.

 

[Spuddler]

Scrape back the lead where you think it is going to join with the other piece with a sharp knife, then apply flux to these areas.
Heat up until the lead is warm enough to spread solder on the areas to be joined.Then join together and hope for the best.
I did some lead flashing over a conservatory like this and is still ok

Also keeping the lead indoors by the radiator to dry it right out helps too

 

[Adeptandy]

Scrape back the lead to a clean shine on both mating surfaces, then cut a 10mm wide strip of lead and scrape clean on both sides. If you have oxy/acetylene then put the small brazing jet in, heat the area on a small flame until the lead starts to melt/form a molten pool, then use the lead strip like a brazing rod and feed it in and move along like you would brazing, No flux needed. its a bit fiddly, but satisfying when you get it right.

 

[mushnt grummmble]

And work on a old slate or flat plate

 

[Pond digger]

And don't breathe in!

 

[2wheels]

do you remember the old stone land rollers with an axle fixed into the end? i remember 1 of these axles coming out of it's lead seating. cleaned out the hole, inserted the stub axle and filled it with lead by using strips of lead instead of welding rods in the arc welder. worked a treat.

 

[Welsh Farmer]

... and then if all those tips fail then my advice is to send it to @Spuddler as he seems to know how to do it ... simples

 

[pycoed]

The proper torch tip for "lead burning" has a tiny oxy/acetylene flame about 1" long. As others have said, joint must be scraped to show bright metal. A strip about 1/4" wide of the same lead is scraped bright both sides to use as a welding rod. Tallow is used for flux on the edges & on the welding rod. It's easy to blow holes on the modern thin (4lb?) lead. The old stuff used to be 9lb/sq.ft.

 

[Dry Rot]

Wasn't it the old pump up blow lamp that was used to get the lead into a plastic state at a joint, then mould it by wiping with a tallow impregnated cloth? The end of one pipe was flared so it would fit over the next. You had to put a little ring of string or rope around the pipe that came out of the top of blow lamp cylinder, pour some methylated spirit on it, and set it alight. That would heat the top of the lamp up so it would burn. Then pump the little pump on the side to get up the pressure. You'd get a pretty good heat from one of those things, at least equivalent to a modern propane torch. The solder came in sticks about a foot long by 1" x 1/4" cross section.

 

[pycoed]

Wasn't it the old pump up blow lamp that was used to get the lead into a plastic state at a joint, then mould it by wiping with a tallow impregnated cloth? The end of one pipe was flared so it would fit over the next. You had to put a little ring of string or rope around the pipe that came out of the top of blow lamp cylinder, pour some methylated spirit on it, and set it alight. That would heat the top of the lamp up so it would burn. Then pump the little pump on the side to get up the pressure. You'd get a pretty good heat from one of those things, at least equivalent to a modern propane torch. The solder came in sticks about a foot long by 1" x 1/4" cross section.

Yes - that was for joining lead pipes which had a wall thickness of >1/4" so these "wiped joints" could be made IF you had sufficient skill. I've still got a couple of these & the prickers to keep the jets clear.
Lead burning as described above was used for thinnish lead for custom made flashings & spouts etc.

 

[Adeptandy]

And work on a old slate or flat plate

....last one I made up, I welded it on a half sheet of ply, nice big flat area for the job and hardly marked it

....but as said earlier, hardly worth the time if busy, tend to buy them ready made nowadays when installing WBS's,