Where are you sourcing screws and other vintage lens parts?

ajs

ajs

Anthony
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I've had this nice little Canon 35mm f2 LTM lens for a couple years that's been a little wobbly and (notoriously) a bit tight to focus. I set out to adjust the wiggle and (after having all the aperture blades fall out and learning how to reassemble that fun mechanism) upon reassembly lost the aperture control 'screw'. With my tweezers tweezing a little too confidently, this 1cm cylinder of dull grey metal flew off to the void (berber carpet) bouncing off, I presume the wall, with a 'tink' 'tink' and no chance of being found again. I even tried fashioning a metal finder out of a piece of angle bracket and some neodymium magnets and scanning every inch of the floor.

I'm having a heck of a time finding anything online about screws for a 50+ year old lens or even what the proper term for this "screw" might be. The screw's more of a threaded post. It slides through a mechanism on the aperture ring and screws into the inner assembly for the aperture blades. I was able to find a technical diagram of a 35mm 1.8 lens here i.imgur.com/oyfmiE5.png where the part L2235 is essentially the part I'm in need of.

I've emailed a couple US based camera stores who seem to have a decent catalog of parts but I've yet to hear back. Is there a secret source any of you have to get little nuggets like this?


IMG_2531.JPG
 
I don‘t have a source but what you are looking for is called „Madenschraube“ in German. Maybe that helps…
 
I'd probably cut a replacement from a generic miniature screw having the correct thread size and pitch. A rotary tool equipped with carbide cutting disc is your friend here. I've got a bunch of small fasteners which I salvaged over the years, but you can buy new ones from companies specializing in model railroading supplies, such as Northwest Short Line.

If your screw requires a shoulder, either start with a screw which has one, or slide a piece of metal tubing over part of the screw. K&S Precision Metals is another familiar presence in the hobby trade.
 
Chriscrawfordphoto said:
If you need the rest of the diagram for the 35mm f1.8 lens, we have it on the Learn Camera Repair website

learncamerarepair.com

Canon Rangefinder Lenses Exploded Diagrams

Covers Canon LTM Rangefinder Lenses and Canon Universal Viewfinder
learncamerarepair.com

Unfortunately, we don't have any diagrams or service manuals for the 35mm f2.
Click to expand...

Thanks! This gets me one step closer. The part L2235 is referred to as "screw pin for aperture leaf movement ring".
 
I depend on Dumb Luck and Lots of Junk Parts Cameras and lenses. Many of these parts were in common on other cameras and lenses, across manufacturers. It also helps to limit work to a very few lenses and cameras. The part you describe is similar to many lenses of the period. Sometimes lining a bunch of similar parts up and trial and error is required.
 
Calzone said:
Let me look into my camera screw salvage zip lock bag. I saved screws from dead Linhof film backs and other cameras.

An approximate diameter and length would be helpful.

I’m a hoarder.

Cal
Click to expand...
My best guess is 1mm x 8mm. From what I’ve found today, the diameter might be referred to as M1. Assuming this is indeed metric, there are also M1.2, M1.4, M1.6 😕. I appreciate it, Cal The Hoarder.
 
You can have the screw made. You can likely find a machinist who can make something like this. Some jewelers also have the lathes to make these. Can search on Reddit, Instagram, or YouTube for some hobby small parts machinists who would probably make up the part you need as long as you can get some dimensions.
 
Partially threaded slotted headless screw. Could be within DIN 427 / ISO 2342 (DIN is German industrial standards, ISO is international standards). There is a M1X8 listed, though likely difficult to buy at low quantity. The "M1" is the major (outside) thread diameter, meaning 1.0mm. Metric thread pitch is typically standard corresponding to diameter, M1.0x0.2 represents 1.0mm major diameter with 0.2mm between adjacent threads (measure 1.0mm between six threads). For the DIN 427 / ISO 2342 M1X8, it's understood 0.2mm is the thread pitch, 8mm is the total length, and there's a 1.2mm long threaded region. There appears pricing of this screw in quantities of 1000's at, "cisotrade.com".

Trying to find this screw, or one adequately similar, from another lens would likely be an easier path than buying 1000 pieces from a distant place.
 
Anthony,

PM me your snail-mail address.

I will send you 4 screws from defunct Linhof Cine Rollex 70mm film holder/magazines.

One pair are 10mm overall in length and the other pair almost 13mm in length.

All these screws have a sewer cap head with a slot that is about 2 1/2 mm in diameter. You could have the head turned down, or perhaps you have a Unimate or small lathe.

The alternative is to file off the head and cut a slot.

Know that the shaft is fully threaded. Don’t know if this works for you. I’m sending spares so you can play around and experiment.

Send me a dollar to cover the postage.

Good luck.



Cal The Hoarder.
 
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Calzone said:
Anthony,

PM me your snail-mail address.

I will send you 4 screws from defunct Linhof Cine Rollex 70mm film holder/magazines.

One pair are 10mm overall in length and the other pair almost 13mm in length.

All these screws have a sewer cap head with a slot that is about 2 1/2 mm in diameter. You could have the head turned down, or perhaps you have a Unimate or small lathe.

The alternative is to file off the head and cut a slot.

Know that the shaft is fully threaded. Don’t know if this works for you. I’m sending spares so you can play around and experiment.

Send me a dollar to cover the postage.

Good luck.



Cal The Hoarder.
Click to expand...
You're awesome! PM coming.
 
You should invest in a powerful magnet to scour your carpet, Anthony. Saved my butt many a time. I got one that is three inches in diameter on an extendable handle so I can poke it into areas where I can't reach by hand. It came from a local hardware store and was marketed as a nail/screw picker upper.

PF
 
Good suggestions for magnets. If you have an old hard drive lying around in need to recycling, those suckers have incredibly powerful magnets inside that you might want to avail yourself of.

I have a couple on the fridge and can barely get them off - they are so powerful.

www.makeuseof.com

How to Take Apart a Hard Drive and What to Do With the Magnets

All mechanical hard drives contain rare earth neodymium magnets. These can be expensive to buy, but old hard drives can easily be harvested for these precious materials?
www.makeuseof.com www.makeuseof.com
 
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A magnet is a great idea.

I have this 2 1/4x2 1/4 inch cube that pretty much machinists use that has a 1/4-20 thread. Also used on optical benches and optical tables. It features a toggle like lever to align two sets of magnets to basically lock the unit.

Anyways, now you have two options…

Cal
 
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