Chris's camera pages
Retina shutter retaining ring dimensions
The shutter retaining rings in Kodak Retina cameras are difficult to access with common tools. These dimensions will help you make suitable tool.
This is the retaining ring for a Retina IIIc type. The retaining ring has a very narrow, around 0.5mm, larger diameter section on the opposite end to the tool slots. The outside diameter at this widest part is 27mm, the outside diameter of the main body of the retaining ring including the end with the slots is only 26.75mm. The retaining ring is 4.94mm end to end.The internal diameter of the mount for the shutter measures 27.2mm, so any tool must be smaller in outside diameter than this figure.The slots for a tool to engage are 1.52mm in width and 1.2mm in depth.The outside diameter of a typical Xenon rear lens group is 24.2mm, so the internal diameter of a tool should be at least this figure.A good tool I have here measures 26.17mm in outside diameter and 24.2mm in internal diameter. The head of the tool should allow for the rear lens group, so a recess 9mm deep will do this nicely. Bear in mind that the tool must pass through the film gate, so the sides will need to be milled down to say 23mm in width. The style of tool can be varied to suit what you have available. Here are three tools I currently have, one is a one-piece tool, one has a tube handle welded to the business end, and the other is of a two-piece construction.
So, what about the Retina IIa and earlier cameras? The retaining rings on these models are slightly different, most notably the wall is thinner. They have the same internal dimensions but the outside diameter for the main part of the ring is 25.81mm, again with a slightly wider base that this time measures 26.05mm in diameter. The internal diameter of the mount for the shutter measures 26.22mm. Depth requirements to accommodate the rear lens group remain much the same.
