Dimensions of the Minox tank rings

<p>Can someone measure and report back exactly how big the expansion rings are for the shorter film lengths in the Minox tank? Intuitively the length is the most important dimension and the ID/OD should be such as to make loading them in and out easy, as in non-jamming due to too perfect a fit?</p>

<p>On my tank I can wind 1 m of string from the hook to the top end of the spiral.</p>

<p>The insertion ring is not a tube, it is a section of a cone<br>

Height, 25.00 mm<br>

outer diameter small end 41.58mm, large end 42.27 mm<br>

inner diameter small end 34.94mm larger end 35.22 mm<br>

measured with mastercraft digital caliper<br>

DIY USE the smallest dimension, made out of plastic tube</p>

<p>Thanks again, Martin. It is s truncated cone, then and I presume it is to reduce the chance of a 36 exp film pulling right out of the cassette? The saving in developer volume would be inconsequential to me.</p>

<p>Murray, I don't know why the Minox tank ring is a truncated cone. The tank cavity probably<br>

Or could be simply due to manufacturing variation. If it was intended to be one end larger than the other, then there should be a marker on it, indicating which way to go in the tank<br>

first</p>

<p>The ring insert depends upon which tank you have. Later tanks only accept 36 exposure and the ring for it to reduce it for 15 exposure. There are 36 and 15 rings for the earlier versions.<br>

http://www.submin.com/8x11/collection/minox/accessories/developing_tanks.htm<br>

See photo at the bottom of the page showing the variations in the developing tank. It did not really change much since the first Riga one.</p>

<p> </p>

<p>Thanks, Gerald. From the pictures I have the middle spiral. No metal spring clip and no white paint. The arm pressing against the spiral is bakelite.</p>

<p>With a wide bootlace I measured 75cm from the cassette to the clip. So, allowing 12mm/frame and spare frames at the start and finish, it would seem I have the 50 exposure+ tank and reel.</p>

<p>Thank you for that.</p>

<p>A Pal of mine had to develop a roll when the tank was home. He rolled the film over a washed read vine bottle, and since he was a slicer, he had a 50 roll in the cassette, stuck the end with Duckt tape, developed in a water Caraffe and later made some surprice Prints in the local Photo Shop for the Bithday baby.<br />My Tank has a cone formed center for the 50 roll. Always emulution uotwards.</p>