I've just finished a restoration project on some Regency balconies. They had a lot of collars missing. They were under a lot of paint and rust, but they were clearly square collars.
Till now the square collars I've seen have been either fabricated (pinned/tennoned) or cast iron. These ones were cast on in lead.
Now, I understand that a lot of people have reservations about lead, but it is actually great stuff. It is the epoxy of historical ironwork, and was used a lot in iron-to-iron fixings, including on-site fixings. It is easy to work, and quite strong.
Anyway, here follows the method I used to replace missing collars, which had mostly been blown of by rust.

1. Original collar;

2. Where the new collar needs to go;

The collar mould; 1" square drilled down the middle, with two little tabs on the sides, held together with welded on bolts ad nuts;

Put the mould round the joint;

Clay!

Jam it in all the nooks

Lead poured

Sprue cut off;
(the sprue is where you pour molten metal in)

mould off;

Flash cut of with knife and chisel, cleaned up with EDM stone, et voila!

very cool love the jig

Thanks for sharing.

If you have problems using lead there are alternatives. There are many low melting point alloys that do not contain lead. Thank you for sharing that's a nice trick. I have seen it before but not explained as clearly and simply.

Thanks for sharing this!

dan thats very cool :) i love the process, and indeed the material. great pictures, that has given me a lot of ideas. thats blimmin great to see that is :)

nice work Dan. good to see

Thanks for the kind words, everybody.

If you have problems using lead there are alternatives.

I actually like lead. Lead is my friend.
However, I should have added the necessary "outside voice" caveat;

NEVER USE OR BE AROUND MELTING OR MOLTEN LEAD WITHOUT A FACE SHIELD AND RESPIRATOR!

Or at least goggles (not safety specs), and definitely a respirator.

Did you need to do anything to the mold to prevent the lead from sticking? I recall having to "candle" sinker molds to soot cover them or sinkers would stick in the mold making fishing tackle. Your mold is much more massive.

Is anything done to the ironwork to encourage the lead to stick?

Was this done in place or in the shop?

Very nice results.

Phil

Phil, this was done in-shop, and I didn't do anything to make it stick or not stick to the work or mould respectively. It didn't even occur to me that it would be an issue. Perhaps my innocence protected me (wouldn't be the first time!)?

the lead wont have actually Stuck though will it? it will just grip on where its cast to fit and sneak in under little bits surely? i have found lead releases from any plaster things i have made for it, although yes you do have to make sure its DRY or you will get lead splattered allover yourself, thus the goggles facemask etc bla bla bla. lead is definately a friend though it is amazing stuff. you just have to not eat it or breath it or anything. it looks and feels Grrrreat :) i really like that you bothered to do that process :0

i really like that you bothered to do that process :0

What else could I do? I actually made up the contoured bar in mild steel with a mind to fabricate them, but then I thought "I've got to do 30 odd of these suckers. That means about 250 perfect 45 degree angles, and a lot of fiddly tig welding".
So, as usual, the "proper" way turned out to be quicker.

quite - what else Could you do? the perfect angles sound scarey... i suppose you have to go the extra mile on restoration work. it looks flippin great anyway. nice one dan. p.

Great jig,
For the next lot, Beyer silicones a european(German) company have great 2 pack silicones that will take the heat of molten lead(some will do aluminium/brass).thus making the mold is easy-you just need a small box and use plasticene to mould a sprue. The local guys will even show you how to make the 2 part block, that is nifty!
I also use lead instead of epoxy to fix wrought iron ballusters(the old fasioned way) if you ever need to reposition/remove just warm the balluster with a oxy torch and "Bob's your aunty" not so simple if you have epoxied the suckers in!

Interesting, thanks for that, Ian. My Dutch buddy said that he has done this just using clay as a mould. I guess it must have been bigger stuff because it didn't work on these guys. Too fiddly.
But as you say, if they don't work, just hot them up and start again.

Thanks for the kind words, everybody.



I actually like lead. Lead is my friend.
However, I should have added the necessary "outside voice" caveat;

NEVER USE OR BE AROUND MELTING OR MOLTEN LEAD WITHOUT A FACE SHIELD AND RESPIRATOR!

Or at least goggles (not safety specs), and definitely a respirator.

Nonsense. I used to chew on lead when I was a kid, and I am.........uh............. I guess that might explain why I am as I am and not the absilute ruler of the TRI-STATE AREA!!!