My cousin had a dockyard apprentiship so was pretty good a metalwork. Walking home up Chatham high street, he'd pull all these old fusee clocks out of skips,take them to work next day, (don't think they did any "work" it was all Union controlled)Get thick sheet brass from the stores ,measure and drill all the pivot points and cut fancy frames. Remember ..dockyard taught.. no file marks..had to be perfect...not a blemish.. so then..
Swap the fusee guts into the new frames , then down the junk shop and buy a victorian stuffed bird in a glass dome..chuck the bird, coz you only want the old rippled glass bit ,and there you have ...a valuable.. "antique" skeleton clock ..

And it didn't matter if you got it wrong and it didn't go ..no one expects an antique 150 year old clock to work anyway. !!!
So , then to the antique auctioneers...every week ! And this carried on for quite a while, until the auctioneer became suspicious... 'Ere 'Arry.. where you getting all these skeleton clocks from lad?? And he got rumbled !
Bit like Escort Mexico's today !!