RZ67II: Release Failure From Broken Cocking Gear Drive Studs
Originally posted on Instagram. Notes from the repair bench, kept here as a searchable archive. View the original on Instagram
Servicing an RZ67II. This camera came into the shop with a shutter release issue. Would not work in electronic or mechanical mode. This indicates to me that the problem is in either the cocking gear or the wind shaft parts.
Photo three shows the cocking gear assembly removed from the camera. Externally all looks fine, but the view inside as seen in photo four shows that the driver (black part in the middle of the photo) has two broken drive studs (one of the broken pieces is to the right of the driver). The solution is replacement of the complete cocking gear assembly.
After replacing the cocking gear assembly final adjustment to the timing is made with the R-5 cocking angle gauge as seen in figure five. The cocking ring should be set so that the start position is 68 degrees and the maximum cocking angle is 110 degrees. If these numbers are off, the lens either will not cock fully or be unable to detach from the body.
For interest, photo six shows the lens mount lifted up and you can see the mirror governor on the upper right. This slows down the mirror as it rises so that it does not slam against the top of the mirror box. Also, you can see two of the washer shims at around two o’clock and two at around eight o’clock. These are put in to adjust the bayonet ring for flatness in respect to the film plane. The spacers come in four flavors, this camera had two 0.2mm spacers and two 0.05mm spacers.
Photo seven shows the final step: a body cleaning with an official Mamiya micro fiber cloth.
A final note to RZ67 users: please be gentle with your camera as repair parts for the RZ are in very short supply
