Convertible lens aperture ring engraving/replacement?

[Donald Qualls]

I've got a 150 mm f/5.6 Componon in shutter, and I've been quite happy with the results using the whole lens or rear group (I understand the front group is less excellent, and may have focus shift, but I have a hunch it won't change the answer here).

I know S.K. Grimes can and will engrave and mount aperture rings for convertible lenses -- but I also know they aren't afraid to charge what their service is worth. Are there other workers who can do this work and do it well, and if so, what will it cost? And would I need to send the entire lens and shutter, or only the shutter and information on what lens to engrave for (makes a significant difference in shipping and risk)?

 

[MarkS]

I would consult other repair shops to see if they would tackle such a project. It shouldn't be that expensive. Or... find a 150/5.6 convertible Symmar and adapt its markings to your shutter. Perhaps a member here has one of those, and could provide an image of the f/stop markings.
Can't argue SKG's quality and professionalism, though. You might ask them what the cost might be...

 

[Donald Qualls]

You might ask them what the cost might be...

I had understood they were steep, but I'll try looking them up and sending an inquiry.

 

[OAPOli]

I made a custom scale recently. I stuck a piece of paper on the native scale and marked the f/stops by eyeballing the pupil diameters with calipers.

I photographed the scale on my copy stand and modeled it in CAD. I 3D-printed a few prototypes to test the dimensions and to make some corrections.

I brought the file to a local shop that does laser cutting and engraving. This was nice because I could supply the material and watch it happen. The guy also made some corrections to the DXF file.

It appears that the aperture pointer's angular position is proportional to the aperture diameter.

 

[ivan35mm]

I made a custom scale recently. I stuck a piece of paper on the native scale and marked the f/stops by eyeballing the pupil diameters with calipers.

I photographed the scale on my copy stand and modeled it in CAD. I 3D-printed a few prototypes to test the dimensions and to make some corrections.

Great work!!

 

[Donald Qualls]

I made a custom scale recently.

Nice! I've used mine by manually converting the aperture values using the known focal lengths, but it'd be easier/faster to have a scale engraved. Maybe I'll just make a new on myself. First, though, I need to figure out how to get the original one off...