I collect these weights along with cast iron scales weights etc if cheap enough at the local boot. So far I have machined about 10 per cent of my total stock without a problem. In fact it machines very well indeed. The only stuff that is variable is CI sash weights. Some of mine are "untouchable".

Rik.

You take pot-luck with this stuff, a while back someone reported opening up a heavy lamp base to find it was made of compressed swarf and resin. One of my weights was a sort of rusty concrete. If you win, smile. If not try again.

Sash weights are notorious. I think it's because many foundries made them as a quick and dirty sideline. Any left-over molten metal from the main job would be carelessly poured into a handy mould. Because they're only rough window  weights, slag and waste could be thrown in, the type of cast-iron doesn't matter, sand would get mixed in, and no-one worried about chilling. So sometimes you get good quality metal, other times awful.

Dave

Edited By SillyOldDuffer on 01/08/2018 10:42:14

In the early days when Taiwanese machinery was the predecessor to "Chinese" machinery, the same question was put forward re the cheap weightlifting sets that appeared for use as flywheels. They seemed to be the same as the sash weights for material quality. Paint hides many sins.

Regards Ian.

Tried to use sash weights once,never again ! they are CRAP,and I mean CRAP !! The only thing they are fit for is in balancing windows,which I suppose is what the were made for. Not much use for anything else.

Now Aldi,s offering,I cannot comment on that,but I would approach it with caution. Why would they use good cast iron in something like that ?