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Harv
Rating: N/A
Votes: 0 (Vote!) | | Posted on Tuesday, September 27, 2005 - 09:47 pm: | 
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I've restored an Agfa Ventura 69 and managed to separate the frozen focusing lens and remove the old grease. Problem now is that the lens is quite sloppy in the threads - so much so that the focus shifts. Does it now need a specific type of grease in the threads to firm things up? |
Winfried
Rating: N/A
Votes: 0 (Vote!) | | Posted on Wednesday, September 28, 2005 - 12:07 am: |
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Usually there is not too much play in the focussing threads. However, there have been many postings concerning re-greasing lenses, helicoids etc. I use silicone grease. You should avoid any mineral-oil based grease, most greases used by machinists are like that. They may bleed out and leave residues of vapor on the lens elements. |
Dan Mitchell
Rating: N/A
Votes: 0 (Vote!) | | Posted on Wednesday, September 28, 2005 - 12:12 am: |
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You need a small amount of grease to give some damping and prevent drift, too. Search the archives for more information since this has been discussed several times. Here are my choices:
1) The best grease for lens focus I've found is Nye damping grease. It's expensive and may not be available except through mail order.
2) Second choice is silicon lube gel. This should be available in hardware or electronic stores.
3) Last choice is auto chassis grease. This works well, but beware that the petroleum in the grease will eventually migrate or dry out and the camera will then have to be serviced again. Only use this if you can't find something else. |
Alex
Rating: N/A
Votes: 0 (Vote!) | | Posted on Thursday, September 29, 2005 - 01:12 am: |
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I'd echo Dan's suggestion number 2. I've been using a tube of silicon grease I got from an electronics store (Maplin in the UK), and it's worked perfectly on all the Agfa and Zeiss folders I've worked on, applying the grease by lifting a few tiny drops on the end of a cocktail stick or toothpick. At the rate at which the grease is required, my tube of it will last me around eight hundred years. |
Harv
Rating: N/A
Votes: 0 (Vote!) | | Posted on Thursday, September 29, 2005 - 10:18 am: |
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Thanks for the info gents - I'll try the silicone. No idea why the threads are so sloppy but there is enough back and forth movement to affect the infinity focus. I have two others with Agnar lenses and they're beautifully sharp. |
