Help Me Understand How This Compound #5 "Interfaces" with a Lens

[ame01999]

I bought a Compound #5 on eBay for my Petzal brass lens. Predictably, it came with a lens attached. I don't need the lens, so I unscrewed the front portion and back portion of the lens, leaving me with this.

What confuses me (and worries me): the rim on the front remaining does not seem to unscrew, and it was perfectly thread-sized for the Kodak lens that came attached. Was the shutter somehow "made for" the specific Kodak lens, and thus will not take another lens? Or is this seemingly permanently attached rim, perfectly threaded for the front of the Kodak lens, just a trifling thing that S. K. Grimes can easily deal with in shop?

Other thing I'm mystified by: via measurement, this is definitely a Compound #5. However the labeled speeds go above 1/50th. I'm stumped.

 

[Dan Fromm]

What are the shutter's dimensions? In particular, the inner diameter of the front tube. This post https://www.largeformatphotography.info/forum/showthread.php?23904-Compound-shutter-sizes on LFPF gives dimensions for Compound III, IV and V shutters.

The shutter was not made for the Kodak lens that was mounted in it. The lens' cells were threaded to fit the shutter, which is a standard size. Lenses mechanical designs conform to the shutters they are mounted in.

If your Petzval lens has an iris diaphragm its glasses will be in cells that might (great stress might) be unscrewed from the barrel. If so, they probably won't work with the shutter -- wrong threading, shutter's tube length wrong. The usual solution is to mount the lens in front of the shutter via a cup-shaped adapter whose front accepts the rear of the lens and whose rear screws into the shutter's front tube. If the lens is so fat that it impedes access to the shutter's control, then the shutter is hung in front of the lens via an adapter whose front accepts the shutter and whose rear screws into the lens' filter threads or slips over the front of the lens' barrel.

FWIW, I have an industrial (no diaphragm) Compound V that I hang in front of a 900/9 Apo-Saphir, a fat and very heavy lens.

 

[lobitar]

On account your photo is fuzzy where the timing wheel is placed (at the top of the lens) it's not clear what you mean by 'labeled speeds go above 50'. But obviously it IS a no 5 Counpound shutter you have acquired - only apparently in an early configuration with a flat speed-control wheel instead of the later wheel version with tapering sides. I haven't seen this particular version before, whence it could have been helpful with a clear photo.
You cannot dismount the front ring (for mounting the front half of the Ektar lens or any other lens) - the ring is machined in one piece with the innards of the shutter.
You seem to be missing the aperture scale, but ofcourse could be an easy fix with a paper scale or the like. You will have to calibrate at any rate.
But congrats with an interesting and rare shutter - hope you become friends!

 

[Ron (Netherlands)]

It seems that the conic dial (with numbers at the rim) were introduced in 1910 (compound shutters intro in 1903/04 with 'flat' dial)
see here for the differences: http://www.earlyphotography.co.uk/site/entry_S47.html

info on the different sizes: https://lensretro.com/2019/01/05/compound-shutters/