russell Posted June 14, 2007 Share #1 Posted June 14, 2007 Advertisement (gone after registration) I've one of those 1980s pre-asph 35mm Lux that can only focus from 90cm to around 3 to 5 meters. After that the protective shroud around the rear glass hits something in the M8 and makes it impossible focus on further distances. Rather than wait and send it into Leica, who might only screw up the focus (it's spot on for the distances it can focus on), I'm thinking of filing it down myself. It cannot take too much I tell myself. Has anyone done this? Which part of the shroud needs to be filed. I'm thinking it only a small part at the bottom rather than the whole circumference. Any thoughts? Quote Link to post Share on other sites More sharing options...
Advertisement Posted June 14, 2007 Posted June 14, 2007 Hi russell, Take a look here How file down a pre-asph 35mm Lux?. I'm sure you'll find what you were looking for!
Shootist Posted June 14, 2007 Share #2 Posted June 14, 2007 Any thoughts? Yes. I wouldn't touch the rear of the lens with a file in any way, shape or form. Not unless you feel like destroying the lens. Just think of all the brass filings inside the focus screw and possibly inside the lens itself. This is better left to a qualified Leica lens service person. Whether at the Leica factory or a independent service person. Have fun and let us know what happens. Quote Link to post Share on other sites More sharing options...
marknorton Posted June 14, 2007 Share #3 Posted June 14, 2007 I agree with Ed, you should certainly try to do this yourself. It would be interesting though for you to post a picture of the rear of the lens when set to infinity focus. Quote Link to post Share on other sites More sharing options...
colorflow Posted June 14, 2007 Share #4 Posted June 14, 2007 I've one of those 1980s pre-asph 35mm Lux that can only focus from 90cm to around 3 to 5 meters. After that the protective shroud around the rear glass hits something in the M8 and makes it impossible focus on further distances. ......QUOTE] I have the Canadian version of this lens and no problem at all with focusing at any distance. Interesting... Alan Quote Link to post Share on other sites More sharing options...
russell Posted June 14, 2007 Author Share #5 Posted June 14, 2007 I knew someone would mention the brass filings. I dont think that's a big of an issue is it? I'm thinking the area that needs to be filed down is rather small. And people file down lens frameline indicators (old 35mm lens for the M3) all the time without removing the mount. Do they worry about the brass filings? Is gravity and a more humid room enough? I'm willing to risk a little because of all the nightmare stories of sending lens off to Leica and it taking months now and also having them returned with the focus in even worse shape. Plus I'm sure they'll send a nice bill along with it. What I'm trying to pin down is exactly which part of the shroud is causing the problem.... Thanks Quote Link to post Share on other sites More sharing options...
charlesphoto99 Posted June 14, 2007 Share #6 Posted June 14, 2007 Send to Don Goldberg (DAG). He 's an ex-Leica tech in the mid-west who has a quick turn-around time (used to be better till the M8 but still twice that of Leica) and fair prices and is used to doing custom work like this. Google for contact info. I wouldn't touch the lens myself. Quote Link to post Share on other sites More sharing options...
jaapv Posted June 14, 2007 Share #7 Posted June 14, 2007 Advertisement (gone after registration) If you have a fair idea of what to file off I would not hesitate to do so myself. A bit of grease on the tool to catch the filings, a bit of duct-tape cut to shape to cover the threads etc, probably 10 minutes work. I'use a Dremel tool. If you send it in it would probpbly cost more than a rigid Summicron with scratches or fungus. Same optical cel in a different mount exchange the lens. Quote Link to post Share on other sites More sharing options...
carstenw Posted June 14, 2007 Share #8 Posted June 14, 2007 To try to find out which part to file, you could put something on the back of the lens, and see where it lands on the camera. I would suggest some grey marker ink or something like that. Not a lot, just to get an idea. I have a Dual-Range Summicron whose focusing cam hits the inside of my M8, so that I can only mount it pre-focused at 90cm. Since your lens stops somewhere in the focusing range, try first focusing the lens while holding it in your hand, and see what moves at all. Perhaps the focusing cam is the problem here too? That is probably the only part moving when you focus. Also post a photo of the rear of the lens, so that those who are more familiar with the lens construction get a chance to guide you. Finally, I would not use a dremel, but a hand file, to control it very carefully, and especially to control the where the filings land. Keep in mind that there is no guarantee that you can even do this. You may have to change the shape of the cam to stop it hitting, but this would throw the focusing off. Take small steps. Quote Link to post Share on other sites More sharing options...
charlesphoto99 Posted June 14, 2007 Share #9 Posted June 14, 2007 How much is one of these lenses worth? Figure that cost against maybe $100-$200 for Don Goldberg (DAG) to do the job. He can take Leica lenses apart in his sleep. Have him do it. A bit of rangefinder adjustment is one thing - a slip of a file and totally destroying the value and usefullness of a lens is another. Quote Link to post Share on other sites More sharing options...
luigi bertolotti Posted June 14, 2007 Share #10 Posted June 14, 2007 Strange problem... I have a very old Lux 35 (Canada, chrome, 1960) ant fits perfectly in M8... backfocuses a little at 1-2 mt, but is a lens which anyway is better not to use wide open, and globally I'm rather satisfied to be able to use a lens which is almost exactly aged as me; I read somewhere (Lager) that the first Lux 35 was basically unchanged for 30 years or so... not exactly, seems from thi thread. Quote Link to post Share on other sites More sharing options...
russell Posted June 15, 2007 Author Share #11 Posted June 15, 2007 I'll try and take a photo of the back of the lens and post it. And the DAG solution doesnt work for me. I'm in Shanghai now and to mail something + the paperwork for customs so I dont have to pay re-import fee + the service fee to file it down + the chance that the lens wont focus as well afterwards (on my M8 - I'm not doubting DAG but I think with the M8 it's better to have the lens matched to the camera since the sensor could also be off or different from his - and I dont want to mail the M8 as well) leads me to a DIY solution. I'm thinking it's only bumping against the bottom part where the (flash) meter is. Either that or the tiny wings on either side in the body. The shroud doesnt rotate. Grease + duct tape sounds like good advise. I'll also humidify the room and hold the lens upside down... Pic to come later... Quote Link to post Share on other sites More sharing options...
russell Posted June 16, 2007 Author Share #12 Posted June 16, 2007 Take a look at the pictures. I dont know if it's the red or the yellow area or both that is causing the block. Also the open part of the shroud doesnt mvoe when changing focus. I've taken two photos. One at 1 meter and the other at Inf focus. If it's just the red then it's much easier to file only the small part at the bottom... Welcome, dear visitor! As registered member you'd see an image here… Simply register for free here – We are always happy to welcome new members! Quote Link to post Share on other sites Simply register for free here – We are always happy to welcome new members! ' data-webShareUrl='https://www.l-camera-forum.com/topic/26619-how-file-down-a-pre-asph-35mm-lux/?do=findComment&comment=282391'>More sharing options...
marknorton Posted June 16, 2007 Share #13 Posted June 16, 2007 You might think of putting something like chalk on the shroud to figure out where it's making contact by looking for tell-tale marks, though there's a risk of dust on the sensor. Be careful though because the lens throat is made of plastic, coated with a non-reflective paint so will be easily damaged. You also need to see how much the shroud moves back as you focus from 3 metres to infinity. If my 35mm is anything to go by, it's about 2mm. Jaap's idea of using grease to collect the filings is a good idea, you certainly want to keep them out of the helicoids. Quote Link to post Share on other sites More sharing options...
gravastar Posted June 16, 2007 Share #14 Posted June 16, 2007 I ground down the shroud on mine, but that still wasn't enough to fix the problem. I didn't want to remove any more because the rear lens element wouldn't have had any protection. My dealer had two other similar lenses which didn't show a problem, their shrouds didn't protrude so far. I don't have the lens with me at the moment (I'm away in Oz) but if I remember correctly the complete lens cell will unscrew from the front of the mount. You then have access to the three very small needle point screws which hold the shroud in place. You need to mark/ink the shroud and mount so you can align them to the same position when you replace the shroud. After removal I ground down the shroud down with wet and dry emery paper, cleaning and replacing it at regular intervals to see if sufficient had been removed. Afterwards I painted where the metal had been removed with mat black paint. As usual at your own risk. Bob. Quote Link to post Share on other sites More sharing options...
russell Posted June 19, 2007 Author Share #15 Posted June 19, 2007 Alright, next step... I put a very small amount of baby power on the bottom piece and then mounted the lens. You can see from the picture below it left some small bits of powder on the shroud which show 1) yes, the bottom has been causing the problem 2) locates the exact point on the shroud. I then put the red marker on either side to make it easier to see. Baby powder was cleaned with a slightly moist q-tip... So I'm thinking that unlike the one poster who almost filed down his entire shroud we only need to file down the one location. It looks to need about 2mm. Still have to check the two "wings" on either side to see if they are also causing a problem... More later... Welcome, dear visitor! As registered member you'd see an image here… Simply register for free here – We are always happy to welcome new members! Quote Link to post Share on other sites Simply register for free here – We are always happy to welcome new members! ' data-webShareUrl='https://www.l-camera-forum.com/topic/26619-how-file-down-a-pre-asph-35mm-lux/?do=findComment&comment=284774'>More sharing options...
marknorton Posted June 19, 2007 Share #16 Posted June 19, 2007 This is how I would do it (YMMV!) Cover the rear lens element with low-tack masking tape strips cut to shape, the type used for home decorating where you do not want it to pull off wallpaper when you remove it. That will minimise the residue when you remove it. Then, wrap tape all around the shroud and over the sides of the bayonet to prevent the helicoids getting contaminated. Then, with the lens held in position, use a Dremel with a sanding "cylinder" to grind down the shroud working to a line drawn on the outside of the shroud. Important to be able to use both hands on the Dremel. Trying to hold the lens with one hand and the Dremel with another is asking for trouble. If you are able to position a vacuum cleaner nozzle on "suck" to catch the metal dust, even better. Quote Link to post Share on other sites More sharing options...
jaapv Posted June 19, 2007 Share #17 Posted June 19, 2007 Another vote for the Dremel. But walk around to a local dental laboratory first and ask for the burr they use to work on steel. That will take off the metal a lot smoother than the bits they sell in the DIY shop, thus minimizing the chance of slipping.And another thing, when you are working with the Dremel, always keep your righthand thumb ( or left-hand if you are lefthanded) firmly in contact with the lens, that will give you all the control and direction you need. Never try and swipe over it freehand even using two hands, that is a recipe for slipping up. Quote Link to post Share on other sites More sharing options...
russell Posted June 23, 2007 Author Share #18 Posted June 23, 2007 Ok, I bought some small files from a model shop and some masking tape and went to it. Take a look at the pic below. The black paint went on right after I took this shot. It's still a bit tight right at inf. But otherwise it looks like I can focus for the entire range now. The only problem is that you cannot mount or take the lens off at inf. The space I cut out is only small enough to clear the bottom piece when mounted. If you wanted to be able to mount at inf then you'd have to file wider to cover the whole mounting-twisting range. That it's a bit tight at inf is good since it will remind me of this... Let's see how it'll work out over time. I'm sure I destroyed the resale value but this has been my fav lens so I dont see selling it anyway! Welcome, dear visitor! As registered member you'd see an image here… Simply register for free here – We are always happy to welcome new members! Quote Link to post Share on other sites Simply register for free here – We are always happy to welcome new members! ' data-webShareUrl='https://www.l-camera-forum.com/topic/26619-how-file-down-a-pre-asph-35mm-lux/?do=findComment&comment=288509'>More sharing options...
russell Posted June 24, 2007 Author Share #19 Posted June 24, 2007 Still a bit tight at inf. I'm sure it's still pushing against that bottom bit on the inside of the camera opening. I'll live with the the lens like this for now. At some point one of the repair guys will have mastered exactly how and where to cut, even tapering it off so you can dis/mount at inf. Also they might be able to machine in some small recesses in the lens mount so the lens can be coded; maybe as the 35mm pre-asph cron?. If any of the repair guys could offer a full shroud job + machined coding I'm sure they'd see alot of the old luxes coming their way... Oh, and one theory I have as to why some luxes dont have this problem; my lux goes down to .9 meters, as far as I know the older ones only went down to 1 meter. Could this have something to do with it? If that's the case I'd still be much happier with my lens since that extra 10cm really makes a diff sometimes Quote Link to post Share on other sites More sharing options...
rob_x2004 Posted June 24, 2007 Share #20 Posted June 24, 2007 Get a large, meduim or fine single cut file, square edge, in case you have to use the edge, and make sure it has a handle. Your local engineers supply will show you which ones if you dont know. You already have your toy file for the clean up. Cut a circle out of ice cream container lid and float that over the exposed glass. Tape the circumfrence with masking tape. Tape a lens cap on the other end too. Jam a rag or a wettex strip down the gap in the barrel to the collar. Rag the whole lot up and set it lens down on the bench. Might help if you use a fresh hack saw to set the ends of the recess, and make a number of cuts along the collar to set your depth and so there is less metal to file out. You can run the masking tape over the cut as well, you will cut and file through it. If you are good enough you could file upside down over the edge of the bench. Clean up following the direction of the collar with a smaller single cut file after you get it down to size. Maybe its the image but yours looks rough as guts. Maybe find an engineering workshop? Worst case is they will get a laugh. Aplogies if the cut you made isnt as cranky as it looks . Quote Link to post Share on other sites More sharing options...
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