Here we go once again...
Not commenting on the unusually thick guillotine blade and the choice of its material one thing should be said - this kind of shutter condemns your camera to horizontal positions mostly. As soon as you tilt it you start to get different results. Sometimes less, sometimes more, sometime off in an unacceptable way, etc.
Even given the limitations, I think an availability of these would help many people make the leap to trying barrel lenses. The guillotine shutter is easy to understand and this one attaches with rubber bands. Mounting packards on lens boards can be intimidating and a hassle and expensive if you have to buy the packard shutter.
If I had any woodworking skills at all, I'd make some of these and loan them out to people. I suspect many people out there would love to be trying old brass barrel lenses, etc, and just don't know where or how to start with it.
But to loan them you would need a lot of different diameters to satisfy your customers' different lenses...
And if you wanted to make a De luxe version you could put a small drop of oil between the blades to make it slip with less friction even in more inclined positions. Olive oil (extra virgin) would do...;-)
I would use plastic, preferably UHMW polyethylene, or cutting-board material. It is very slippery.
Science is what we understand well enough to explain to a computer. Art is everything else we do.
--A=B by Petkovšek et. al.
Ron had this posting last year and I ordered one for my 5 1/2" wide Xenotar lens and it works well. It has a 4" Lees filter slot to put a ND or whatever filter you fancy.