I don't have any originals left but the lead I use to make my own washers is 1.5mm thick. I usually use two washers at a time which is maybe a bit too much so maybe 2mm would be the right size.
On the Butterfly Brand washers I have seen the cross section was square, i.e. the thickness was the same as the difference between ID and OD. Do you plan on casting them or punching them out, Ross? I suppose casting them would be the most economical use of material, if you have a mold made for you.
I can't imagine casting them. I need a new one and I am going to take some roofing lead (from around a vent) and use a metal roller to get it to about the rights thickness then use a large hole punch for the OD and a smaller one for the hole size. I am thinking that the thickness should not be to crucial as long as it is close, it's lead and should smash down a bit.
For the satisfaction of it maybe - I would! Casting them I don't think I would try - not much success with that so far - apart from making lumps - akin to fishing weights. Punching from roofers lead sounds like fun, even trepanning them out. Watching with interest.
Roofing lead is what I've been using for years. With a set of concentric punches it makes it easy. The stuff I have is about 1.5mm thick so usually use two washers together. Has worked every time for me.
I've made quite a few from sheet lead with hollow punches. I've also used solid lead wire formed into a circle and the ends soldered together. Works just as well. What did not work well and started leaking after a while was to form a ring from resin core solder, also with the ends soldered together. Still not quite sure why that was...
Depending on the hardness and thickness of the lead you use it is a good idea to put copaslip on the screw threads when you tighten it up. There is quite a lot of torque and strain to the brass and this way the energy is transmitted to the lead and not to overcome friction in the brass screw threads.
Good try Phil, the trouble with cored solder is you have only part of the volume. It looks like lead - but maybe about 40% by volume is rosin cores. What do you have left over after the magic smoke departed?
Welcome @Flymann , Don't be shy, tel us about your lamps, pictures we love. What tool do you need or referr to ? The washer (seal) can be bought on the internet almost everywhere. Hytta.de is a good web shop too. Washer nr. 90 cost 0,90euro in rubber 1,50euro.
