Question about Wollensak Sunshade and Filter Adapter

I've recently come into a truly ingenious accessory for the 135mm f4.7 Graflex Optar lens on my Speed Graphic camera. The lens hood is also a filter holder. There is an f stop scale on the hood and also a tab that couples with the aperture tab on the lens, so you adjust the aperture by using the scale on the lens hood and turning it to the desired aperture. How cool is that! The filter holder is for a series 6 filter, however the series 6 filters I own all have metal rings on them. I'm assuming the filter needs to be one without the metal ring as mine don't fit. It appears to be held in place by a screw/clamp on type connection. Am I correct in thinking I need a series 6 filter without a metal ring on it? If you don't know what I'm talking about, this eBay auction has one.
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Bill Barber

It really is an ingenious device - I have one on both of my Graphics. My series filters all have the metal rim and work just fine in the Wollensak hood.

I used to have one. If you loosen the set screw for the filter clamp, a series VI should fit in. Perhaps the springy metal ring that the set screw pushes against is a bit bent and is not letting the filter drop into place. When you refer to a series 6 filter without a metal ring, do you mean the retaining ring that holds the filter in the series adaptor that screws onto the filter threads of a normal lens (without the Wollensak sunshade)? I think all series VI filters normally would have a metal ring around the actual glass element.

I hate to admit what an idiot I was being. I was trying to insert the filter on the back side where the hood attaches to the lens. When I flipped it over the filters would go in, but not stay. I took me awhile to locate the really small set screw and get the tightening band rotated so the set screw could do its work. Now it is working just fine. Thanks for heading me in the right direction. Bill Barber

Live and learn... now enjoy.

Someone told me, although I never had the problem myself, that it's important to keep the rotating action of the lens shade well lubricated. If it binds when rotated, it may tend to unscrew the front element of the Optar lens, leading to focus errors.

If you want another really cool and ingenious accessory for your Graphic, look into the Grafmatic film holder--6 shots with "slide action" shuffling of the film sheets.