Inspired by the many lens adaptations going on , i picked up an old projector to attempt one myself,
after some research this is my Frankenleicaony ))
i managed to get 2 leica projector lenses , 90mm f2.5 and a 35mm f2.8 , the 35mm elmaron came with the focusing
tube which was to me very important , the 90mm also fits into the elmarons focusing housing which is nothing but a black tube.
taking into account the sizes and trying to attach it to a m42 helicoid did not work for me , so i ordered an m52 to m42 helicoid which the lenses and its black focusing tubes fitted into , sadly this is not perfect so a little electrical tape did the trick , this will be replaced by a step up ring when it arrives from timbuktu (hopefully)
attaching all this to an m42 to nex does not work , but it works perfectly with an m39 to nex , the 2 adapter to nex were of the same brand so i took out the silver thread rings and tried swapping them over , the m42 thread rings outer rim was 3-4mm wider so out came the file and several hours later it slotted in to the m39 adapter housing perfect , everything works fine , intact beyond my expectations i can focus from about 30cms out to infinity and do some pretty good close ups ,