Thursday, May 8, 2014

Isolette III Overhaul part 2

If you haven't read it, Part 1 is here.

I received my lens tool from Hong Kong and that made getting the shutter out of the front standard a snap.

Next step was to get the focusing ring off and see if I could get the front lens element off. I had to file down one of my smallest screwdrivers to get it into the tiny retention screws holding the focusing ring on. I could barely see them, let alone loosen them. If you are playing along at home, remember NOT to remove these. Only loosen them until the ring comes free. Here are the rear lens element, paper gasket, rear retaining ring and the front focusing ring.

For this I went to my favorite degreaser, Simple Green. A few hours' soak and the front element came right off. It turned the Simple Green a nasty black too. A quick rinse with Ronsol and I was ready to go on to the shutter/aperture. Note that the paint on the numbers of the aperture indicator will come off if you soak it, so remove that piece before you do all of this. Also note thta there are two different screws that hold this piece on. If you keep track of which goes where you won't have to figure it out later. It's not hard though. Look carefully at where they screw in and you will see that the metal is different thickness. The longer one goes into the thicker metal.

The aperture was totally frozen. After asking around, it sounds like this is an uncommon problem. If you don't absolutely have to, DO NOT DISASSEMBLE THE APERTURE!! If you do absolutely have to, be aware that there are 10 aperture blades that come in 4 different varieties. Take it apart carefully and document explicitly where each of those blades go! The blades are made of very thin metal and will tear or crease more easily than you would think.

I got mine apart (they were really stuck together good), cleaned them up and after about 4 tries, got them reassembled. I found that if I put some painter's tape on the back side where the rivets stick through, it held the blades in place a little better. You will lose your mind trying to move the blades into place and keep them in their holes. Don't use clear cello tape. It is too sticky and will be difficult to get off when you go to put the aperture back in the housing.

Notice a couple of things. I work on a sheet of white paper. White cloth might be better at capturing tiny screws that are trying to make a break for it, but the lint and fibers are the price you pay. I work in my kitchen which has a hard laminate floor. If something rolls off the table, I can generally hear what direction it went and then use a strong magnet to find the escapee. The best thing though is to not lose those things to begin with. See that I have taped the screws down to the paper I am working on. I also have a good pair of forceps with a fine point that makes handling little things easier.

So one by one, put the blades into their respective holes. There are a couple of methods to doing this. I chose to have the blades sticking outward away from the center. Then once they were all in their holes, I started rotating them clock-wise. When they start to touch, lift them lightly so that they overlap the adjacent blade. Keep moving/rotating them bit by bit, being careful that none of them leave their holes. Once you have them all overlapping so that it looks like a circle, you can put the retaining ring on top. Sorry, I don't have a pic of that, but it ends up looking like this, with the 'top' rivets sticking through the slots in the retaining ring. You will have to wiggle things a bit to get them all to the right position.



That's probably enough for one post. I will be back to cover the rest of the assembly and making new bellows in subsequent entries.

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