[Leica] To the abyss and back with an Alpa Reflex Prisma, my story of repair, and sleep

[abridge at gmail.com (Adam Bridge)]

What a fascinating account, Vick, thank you for sharing this. Yet
another aspect of life and photography that I never would have even
thought about until I read it here.

Of course if it had been ME there would have been springs and gears
and screws and nails and 3/4" Schedule 40 tubing all over the place by
the time it was over and the result would have looked like the alarm
clock the Mad Hatter assembled in Disney's "Alice in Wonderland".

Thank you.

Adam


On 2/7/06, vick.ko@sympatico.ca <vick.ko@sympatico.ca> wrote:
> To the abyss and  back with an Alpa Reflex Prisma, my story of repair, and 
> sleepliness
>
> A month ago, I bought a jammed Alpa Reflex Prisma off ebay.  It arrived 
> last week, looking in just fine cosmetic condition, definitely far too 
> nice to be relegated to the status of static display or the horrors of the 
> parts bin.  The glass was nice and unmarked, the shutter curtain condition 
> was intact and supple, but the shutter and film wind was jammed.
>
> I searched the web for information on repair, and posted some inquiries 
> and got back some useful and encouraging information.
>
> Of course this story is all written after the fact.  The thoughts and 
> fears before the operation of opening up an unknown camera are much 
> different and intense than after the exercise, with questions such as 
> "what screws are there under the leatherette, how many bizarre lockrings 
> are there that need special tools, etc?
>
> Last Friday I took the basics off, like the lens mount and bottom plate.   
>  The bottom plate is a straight-forward removal, just removal of all the 
> externally exposed screws.  This exposes the complete gear-train for the 
> film advance and shutter mechanism.
>
> The top deck is harder.  I looked under the leatherette, but no screws to 
> be found.  Two cover plates are found with exposed scews around the film 
> chambers, so out they come  Some of their screws are behind shafts, 
> needing special contortions to loosen them off.  Now after the fact, I 
> find that the film spool is removable, and there was a srew behind it.  
> Had I known that the spool was removable, a half hour could have been 
> saved having to trick out a screw with a slender screwdriver and 
> toothpicks.
>
> Removing the top deck also means removng the prism, which isn't too bad.  
> All the screws for the prism are accessible,and this is the first place 
> where I find a missing shaft.  This shaft would provide a more secure 
> attachment of the front of the prism to the body.  On the positive side I 
> find that the prism glass and focusing screen are in really good shape 
> although a bit dusty.  Now removed from the body, the prism will bs really 
> easy to clean.
>
> The top now appears to be loose, and can now be slowly removed.  But as I 
> begin to separate the front and top from the body, parts begin to fall 
> out, namely then lens for the view finder and two parts of its lensmount.  
> This is where the cold sweat breaks out, not knowing where the parts come 
> from, and what order they go back in.
>
> My strategy in these situations of parts dropping out is to consider what 
> the original assembly and design team were thinking.  Neither teams would 
> have had magicians.   Parts have to go back in by logical order, and must 
> be able to be positioned without anti-gravity tweezers or the like.
>
> The front faceplate and top deck ultimately come off as a single entity.  
> The revolutionary aspect of the design is that the shutter dial does not 
> rotate when it fires, despite that the shutter dial is on the wrong side 
> of the camera.  Many cameras of that time did not have a non-rotating 
> shuter dial.  Removing the top deck also exposes both the viewing finder 
> and the rangefinder mechanism.   I can now see what needs to bs done to 
> realign the RF.  It is a simple two-mirror rangefinder design, and the 
> only lensed optical assembly is the viewfinder, not the rangefinder.  And 
> the optical chambers for both the RF and VF are simply lined with black 
> cloth tape for light suppression.
>
> But still no clues as to why the jam exists.
>
> I pull on the curtains and deduce that the first curtain hs no tension but 
> the second one does.  This is sounding like a very common Leica failure 
> mode where a felt light baffle strip can get lodged in the shutter curtain 
> and tape.   But the chambers holding the shutters rollers and spring 
> rollers are still not accessible.
>
> So now Lius's email (from IDCC) on the camera holds the essential clue, in 
> that there is a seperate body housing that is sealed to the main interior 
> housing.  I go around looking for its seams and find them.  I also go 
> looking for where the attachment screws are.   This is one major factor 
> with classical cameras versus modern ones.  With classical cameras, I can 
> be fairly certain that screws and fasterners are what holds the mechanisms 
> and housings together, and not glue or welding/soldering.  Sealng compound 
> are used for light sealing, not structural attachment.  Today, items are 
> sealed or glued together, and are incapble of offering viable disassembly 
> or reassembly.
>
> I find most of the attachment screws for the inner and outer body, but 
> also find that the entire RF mirror assembleis needs to be removed.  This 
> I one area where I will admit that the orignating company had magicians.  
> I hate having to do optical alignments without the necessary optical 
> equipment.  But forging ahead, the mirror mounts and pivots are removed.
>
> The outer shell is then slowly slid free of the body box, exposing the 
> shutter rollers and spring rollers.  Here, I find that the shutter 
> curtains are indeed intact, with only a minor tear on the takeup side, and 
> the tapes are fine.  I also find the errant spring roller and have to 
> remove it.  I slowly separate the shutter curtain from the spring roller, 
> but now find that I have to remove one of the shutter timing gears.
>
> Gear removal is a another area of immense complexity; not so much the 
> removal but the need to properly retime things after.  I mark all the gear 
> locations and have to drive out a pin to remove the relevant gear.  Having 
> removed the gear, the spring roller is extracted, and miracle of miracles, 
> the spring is intact, and only popped loose of its mount.  Reinserting the 
> spring is trivially easy, and the spring roller is cleaned up and 
> reassembled, working again.
>
> Now I merely need to reverse all the disassembly steps, and this is the 
> evil that many repair books end at, i.e. "reassembly is simply the reverse 
> of the disassembly steps.
>
> To move along faster with this story, I reassemble the shutter, and the 
> gear that I removed.  I can now fire the camera with some semblance of 
> proper shutter action, and discover that the gear timing was the cause of 
> the jam.  But this is what took the next 6 hours, discovering that the 
> gear timing is completely off.  I put it down to someone else had played 
> with the gears, and didn't put them back properly.  Hours are spent late 
> at night to determine the correct timing, but finally the correct 
> alignment is found, using the cocked state of the shutter as the reference.
>
> Ultimately, I get the shutter entirely reassembled, but find that the fast 
> speeds are adjusted properly but the slow speeds are completely off.  If 
> adjustments are made to the slow speeds to bring them into specification, 
> the fast speeds are entirely off.  this is a complete conundrum, as the 
> two speeds are locked by the single gear train.  After numerous hours of 
> study and adjustment, I final concede defeat and cheat.  I remove the 
> bottom plate of a second virgin Alpa Reflex and examine its gear train, 
> and one single gear is installed 90 degrees differently than what I have.  
> Moving the gear adjustment on the Prisma brings both speed ranges into 
> spec.  Relief and celebration, and short nap follow.
>
> The rest of the reassembly is pretty much a reverse of the disassembly 
> steps.  The rangefinder realign is another cycle of trial and adjustment, 
> including turning off the room lights and shining a flashlight into the 
> optical train to see where the mirrors are actually pointing.
>
> The missing shaft for the prism mount is fashioned from a sewing needle 
> Holy cow is a sewing needle ever hard!   I'll never consider buying drill 
> rod for shafts any more; sewing needles are far easier to find.
>
> Ultimately, the shutter is working well within spec.  My 4-1/2 year old 
> son can operate the shutter tester and has great fun cycling through all 
> the shutter speeds for me.  The rangefinder is working "well enough".   
> The RF spot isn't quite centered, but to center it would involve another 
> full disassembly of the body plates, something that can wait into the 
> future.
>
> And the camera now looks beautiful and I have the inner peace knowing that 
> it works properly, is properly lubricated, and has now become a "keeper".
>
> Now, if I can only find a lens for it ... anyone out there with lenses 
> from old Alpas that they don't want?
>
> regards
> ...Vick
>
>
>
>
>
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