Category Archives: Tools

I pity the tool !!!

Sometimes yah just can’t win … many cameras utilized specalized manufacturing techniques to get everything together. When servicing these camera’s, you really should have the tools that were designed to work on these things.

One of them is a flexiclamp/ring wrench, the tool to remove the various retaining rings used on cameras without scratching them.

Some are very specific to a camera … which I just found out about the Canonet QL17 G-III. I encountered difficulty getting into the shutter mechanism because the front lens group put up a fight. Most other cameras of this type that I have worked on just required a spanner wrench or a rubber friction thingy … not this camera.

Screen Shot 2017-11-09 at 7.02.50 PM

This tool is used to work on the front lens group (as noted in the service manual).

I can see why this is needed … the group is screwed on very tightly so friction doesn’t work. A spanner wrench is too wide to fit in the tight space. Even using my super strong stainless steel tweezers didn’t work, even though I could force it wide enough to connect to the slots, I could not get enough grip to prevent it from slipping.

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Stop Weining about Hg !!

For anyone collecting/using old cameras you will eventually encounter the battery replacement issue. Starting in 1991/92 there was a restriction on the sale of mercury content in batteries … this lead to the end of all mercury (mercuric-oxide) batteries. Silver-oxide batteries became the best replacement to powering cameras, but this battery used a higher voltage than the 1.35V mercury batteries, which means the older camera meters have to be recalibrated/modified to use them.

WeinCell makes replacements that are of the equivalent voltage … but they ain’t cheap, so here are some alternatives”

The O-ring and Jon Goodman’s 675 adapter are described by Rick Oleson: Cheap Easy Mercury Battery Replacement

same topic by Bruce Varner, here: http://brucevarner.com/PX625Replacement.html

… and here is another discussion: Mercury-Oxyde Battery Problem


Separation, leads to divorce, and a new coupling.

Sometimes you encounter a lens that has some internal blemishes that you cannot seem to clean off … can look like rainbow rings (ring of fire), a cloudy ring round the edge, a crescent beige tint, bubbles, or even a flowery/snowflake pattern … and it always seems like it’s trapped between two lens elements.

This old LTM lens has an almost complete ring haze. Now, it could possibly be just haze on the back of the element … but I suspected it was more than that.  After talking it apart it was apparent that it was separation of the front two elements.

Yes, in fact it is between two lens elements. Most lens designs require two lens elements to be bonded/cemented together (doublet) with adhesive to eliminate the glass air gap. By reducing exposed surfaces, cementing reduces refraction and ghost images from reflections, and allows the use of thinner flint elements. 

Older lenses used Canada Balsam as it had a high index of refraction, which is optically a good thing to have. It is derived from good ol Canadian trees … yup good ol sap … yes, its not just only for maple syrup.

Development of resins to cement elements started in 1785. Eventually changed to a synthetic resin because of WWII … high altitude aerial photography caused issues with Canada balsalm, so they developed a synthetic cement that could handle low and high temperatures … this is the MIL-A-3920 standard optical adhesive. UV curing adhesives appeared in 1966 to reduce the curing time for high production.

When the “cement” has degraded and no longer seals the two elements together, the separation will create artifacts that will change the refractive properties of the lens. Sometimes it is not very visually apparent … sometimes it is. The only real solution is to separate and re-cement them.

This topic has been discussed much on the web … FotomozaicLargeFormatForumskgrimes

With Canada balsam, it requires heating to soften the resin so the elements can be separated. The newer synthetic resins require special chemicals … and in some cases the elements cannot be separated without damaging it.

Once separated, new resin can be applied to cement the elements. Then new resin can be applied to cement the elements … modern day resins are UV cured, so makes it much quicker to get a lens back to working condition.

Sounds easy … not !!! Heating sometimes does not work, or even worse causes the element to crack … and there are cemented group that are encased in a metal sleeve which has to be removed first (without damaging the glass, and you may have to find something to replace it) … or, as mentioned before, it just doesn’t work.

One day I will make a serious attempt at re-cementing … meaning, my half-ass attempt sucked, and I will try again.

Summers Optical makes many different types of synthetic resins for optical cementing … and you can still buy Canada Balsam, as it is still used for microscopic slide mounting and painting.

Sometimes the lens separation is not so bad in terms of affecting the image, especially if it is around the edges like the lens pictured above … but when it sits right in the centre, it will most likely cause apparent visual effects. Mounting this lens on my Sony NEX-6 and taking some shots, I could not really notice it until I got some light hitting the front and the separation starts adding some flaring/fogging.


There be knobs !!

There was one particular “tool” that I mentioned that could be one of the most important ones to have … or have access to … and that is a friend who has a machine shop.

I had completed the work on the Mamiya Six some time ago, but sadly the camera came to me with a missing part … one of the film spool supporters.

I thought, hmmm, possibly my awesome friend Craig could machine a new one for me … and that’s what he did.

The old one is on the right.

It’ not an exact replica, but I was not expecting that, just something similar.

Hey, it works … and looking almost like it’s original is a bonus !!


Some thoughts to start 2017 …

Oily oily oxen free …

Have you noticed I have not used any “oil” yet ?

I mention it in my section of tools.

I am not actually sure if any oil was used in the creation of cameras. Yes, there is the use of grease on many moving parts … especially on focus helicoids and the focus mechanism of TLR’s … but I don’t think oil is needed.

From the many discussions on the web … camera shutter mechanisms/gears are designed to run dry. Without access to the manufacturers service manual, you really do not want to guess what parts can be lubricated with oil, better safe than sorry.

If you add too much oil or the wrong type of oil, to escapements they can slow down … throwing off the timing of the shutter. If you add too much oil then it can leak onto the shutter and aperture blades … which is something you really do not want to gumm up.

I have used watch oil (though I never stated it) on heavy movement arms … but never anything close to the shutter, or apertures blades. When I do use it … it gets applied with something like a metal pin/needle.

Many of the cameras/lenses that I have encountered do have gummed up shutters or aperture blades. Most of the time is comes from old helicoid grease that degraded, liquified, and has leaked into the wrong places … sometimes it is just crud … and sometimes a DIY job.

 

Can’t get enough of that sugar crisp … or at least screwdrivers.

I am always needing screwdrivers. For some reason or another I tend to need one size/type that I don’t have … or is not exactly the right shape … length … etc. Now most of the drivers that I have are ordered online, since they are of very small point size I can’t get them easily … but recently I was at the local hardware store for something and noticed a cheap micro screwdriver set. It was the Home Depot brand, the Husky 8-in-1 Ratcheting Precision Screwdriver.

It comes with eight (yes, as the name says) reversable snap-on tips.

Slotted: 1.5 mm, 2.5 mm Philips: 0, 00, 000 Square: 0 TORX:T7, T15

After using this, I have found that I am using it half of the time … and the Torx is great when I am working on Laptops. The quality of the metal tips is pretty good, and you can get a good grip when necessary. The only thing I really have not used the ratchet, as I keep forgetting that it has that feature. They do make a version without the ratchet and added a twist top (handy for small thin drivers), but they did not have that at my location … and all for $9, yes less than 10 bucks (for you Americans it probaly means $5) !!!

 


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