About to take file to Summicon-C 40/2

[caffeineshutter]

...in order to have the 35mm framelines displayed on my M6 with the Summicron-C mounted.

An external finder is workable, but I dismissed it for various reasons. Using the 50mm frame lines is a bit like handicapping myself. And I don't want to crop the extra stuff that I got under the enlarger. If I wanted to shoot with a 50, I'd mount it and head outside. The 35mm frame lines are good for me, and I'm not shooting close up (have an SLR for that).

With all of that said, I'd like to hear from those who have performed this operation: Tools you used, how you protected the rest of the lens while doing it, and whether I'm making a mountain out of a mole hill. (I understand that all of 1 millimeter needs to be filed down. Simple (?).

Also--how did you keep filings out of the lens? I'm thinking: A magnet, or tape a vacuum hose to the table next to the work space.

Thank you!

-CJ

 

[FrankS]

I used a dremmel tool and masked the rest of the lens, like a doctor masks all but the surgery site.

 

[caffeineshutter]

Good point...

Good point...

Thank you for the advice!

I have no idea where my Dremmel is, so I'm going to use a small file from a set sold for hobby, jeweler use, etc. Given that 1 mm of metal needs to be taken off, I'm thinking it'll only require a few strokes with the file.

I plan on using gaffer tape to protect the rest of the lens. Can anybody else recommend a different type of tape? I'm thinking masking tape might do it, but I'm not sure if it'll leave behind small amounts of stickum which will attract dust....


-CJ

I used a dremmel tool and masked the rest of the lens, like a doctor masks all but the surgery site.

 

[waileong]

Gaffer.

And good luck.

 

[Artorius]

Thank you for the advice!

I have no idea where my Dremmel is, so I'm going to use a small file from a set sold for hobby, jeweler use, etc. Given that 1 mm of metal needs to be taken off, I'm thinking it'll only require a few strokes with the file.

I plan on using gaffer tape to protect the rest of the lens. Can anybody else recommend a different type of tape? I'm thinking masking tape might do it, but I'm not sure if it'll leave behind small amounts of stickum which will attract dust....


-CJ

I use the blue painter tape. Low tack, and no residue. And, it's cheap.

 

[sting-ray]

Just thinking of the medical thing.. perhaps you could stretch some latex i.e. a disposable rubber glove... and then just puncture the lens flange through the glove?

 

[Keith]

I used a small ignition file to do mine and I was amazed at how little had to come off it ... go easy! 😀

 

[ferider]

Forget about tape, just take the flange off and then file.

Roland.

 

[Andy Aitken]

It makes no difference if you file "too much" off but still I think so little needs to come off that using anything with a motor might be overkill - heck I did it with my Leatherman! It's a little hard going until you get through the chrome but then its easy.

 

[caffeineshutter]

Excellent suggestion...

Excellent suggestion...

Hadn't thought of that.

BTW, and FYI, a long time ago I worked for a VAR selling Apple products. A coworker told me an anecdote about a hospital purchasing Palm Pilots for their doctors. To keep everything as clean as possible, each, uh, 'unit' was covered with an unlubricated latex condom. (Apparently the Palms of yore were sensitive enough that you could draw/type on them through the rubber). I think that may even be a more elegant solution than gloves. Sry for too much information there...

So gaffer's tape and latex is what it'll be. Anything else anyone can add in the way of advice or tips always appreciated. In a way I consider this sacrelige; like painting a Delorean or adding an auto trans to a BMW 2002. But I'll undertake this with Barnack the Innovator in mind.




-CJ

Just thinking of the medical thing.. perhaps you could stretch some latex i.e. a disposable rubber glove... and then just puncture the lens flange through the glove?

 

[caffeineshutter]

that sounds like a good idea--

that sounds like a good idea--

However, I have no exploded diagrams of the lens, and [shiver] putting it back together incorrectly--such that the registration could be off--scares me.

Any M body or lens repair sites/pdfs out there?


-CJ

Forget about tape, just take the flange off and then file.

Roland.

 

[ocean7]

I did it on my Rokkor 40/2 which is the same lens. I was a bit scared to be honest but that's really no big deal. You have to file off 1mm or less, just mount the lens from time to time while you progress to see where you are.

I did not cover my lens with condom, it was naked and unsafe but there were so little filings that I removed them with a small paintbrush from time to time. Just watch out where the metal dust is falling, you do not want it inside the lens but on the flange it is OK if you wipe it of carefuly.

If you use a jeweler's file as I did pay attention not to touch the chrome on the barrel underneath the flange because it scratches easily.

 

[ferider]

However, I have no exploded diagrams of the lens, and [shiver] putting it back together incorrectly--such that the registration could be off--scares me.

Any M body or lens repair sites/pdfs out there?


-CJ

It's straight-forward: take the 5 screws out with a good screw driver, and
the mount will come off. You will not affect the registration distance at all.
You can even try the frameline change by just putting the mount on
the camera.

Best,

Roland.

 

[caffeineshutter]

Sweet. Thank you Roland!

It's straight-forward: take the 5 screws out with a good screw driver, and
the mount will come off. You will not affect the registration distance at all.
You can even try the frameline change by just putting the mount on
the camera.

Best,

Roland.

 

[BillBingham2]

Roland is da Man when it comes to this stuff.

I had an old Leica lens done with a dremmal style tool while I watched. When you think about it, the direction the chips fly is the most critical part, AWAY FROM THE LENS!

Taking it off should be straight forward. Just for giggles, mark the mount and the lens orientation (say at 12 o'clock) with a greese pencil (or alike) so you can reassemble it easily.

B2 (;->

 

[JNewell]

Really anal-retentive question. Are these JIS or Phillips heads? How much does it matter, if at all???