Helios 44M-4 where to find a screw

[roby02091987]

Hello everybody!

I've just registered to this forum and I already need your help.
I've recently disassembled my helios 44m-4 in order to let it focus to infinity on my nikon camera. Reassembling it, i've lost one of the four mini-screws that hold in place the m42 screw mount.

Three screws are enough to keep it tightly in position, but i'd like to replace that missing screw, and here is the problem: where can i find such a small screw?

For your information, the screw is 3mm long and 1,5-1,6mm "wide".

Thank you all in advance for all the help

P.S. sorry for my english, i hope everything is understandable.

[tromboads]

surly any decent hardware store would sort you out? There is nothing to exotic about the screws used. At mega worst, if its a smige thicker it will re cut the die when you screw it in anyway.

[thundertwin72]

[roby02091987]

[Lloydy]

I have a box of screws from dead cameras and lenses, and a Helios, so I'll have a look.

[roby02091987]

[caerwall]

I had a similar problem with an internal screw in a Jupiter-3

Tiny little flea-like things and jump about just about as much, and they are all different.

Taking all the usual precautions with trays and things it is still possible for them to bounce on to the floor. I have even managed to find some from the floor. But the best way is too simply contain them in a little plastic box as they are removed. A stacking set pill container size will keep them in order of removal. The best maxim is "don't lose them".

My lost screw remain lost, hardware store screws are completely useless, even a helpful watch repair shop came up with a bunch of watch screws in a "left overs" box but none of them were useful for what I needed.

Common wisdom is to buy a few old "dead" lenses and cannibalise them for screws. But even then there are so many screw types and unless you get a lens that is otherwise identical it is still hard to get the exact same one that you are looking for.

You cannot "cut a new thread" easily as the material is often soft and what you are effectively doing is driving a wrecking bar into the slot. Might work though.

Someone must have made the original screws and my present thought passes from imaginations of someone tending a mini-screw manufacturing lathe to perhaps hand dies and making screws from suitable wire stock on demand. Flattening the head with a small hammer if necessary before cutting a slot is the least problem.

This leaves the questions that I must ask - where can a suitable set of hand dies be found? How do you cut the appropriate size slots in the end of the "new screw" to fit your screwdriver" Finding suitable size wire stock itself would be hard enough but must be easy compared to the answers to the first two questions.

I am sure that there will be many quite interested in setting up their own little screw manufacturing works including myself.

Tom

[Lloydy]

Sorry, I had no luck in finding a screw. But I'll keep looking.

As for making screws of this sort, I spent a few years working on quality control at a company making time clocks and parking meters. In those days the company made all it's own components including the tiny screws. Down to about 1mm they were made on automatic lathes, and under that size they were rolled. It was a nightmare for the quality control guys, some of these machines were making 2 screws a second so if you couldn't get around all the machines for an hour or two there could be a lot of scrap.
But that was back in the 1970's, today modern CNC machines have revolutionized this kind of manufacturing which is why this sort of product is made so cheaply and accurately, whether the cheapness is passed on to the consumer is another matter, as is finding the screw you want !

[roby02091987]