The Beseler 8088 lensboard was designed specifically for the 150mm Apo-Componon-HM enlarging lens, which was difficult to place and remove on a Beseler 4x5 enlarger when mounted on a flat lensboard. It gave about 1" of extension, which sufficed for the rear element to clear the housing. Beseler lists it as discontinued, although B+H show it as a special-order item here: https://www.bhphotovideo.com/c/produ...nsion_for.html

I will be making the functional equivalent of this board with a 50mm mounting hole (the 8088 had a 55mm hole, I believe) for my recently-acquired 180mm Componon S. Unlike the original version, which is assembled from pieces, I'm planning to machine it from a single piece of aluminum in a friend's 100%-CNC machine shop. While we were discussing this project he asked me if there's wider interest in these. Once the machine is programmed, the effort involved in making additional copies is low, primarily material cost and machine time. He estimated the unit cost at about US$100 exclusive of shipping.

So I put it to the community at large - does anyone else want one of these with either 50mm or 55mm mounting hole? Please respond here rather than by private message. We will definitely be making one for me, the question is whether to order additional materials to produce more. The deadline for expressing your interest is December 31, 2019. I'll order materials sufficient to produce the number requested early in the new year. This is a one-time opportunity - we have no plans to do this a second time.

I've posted this on both the Large Format Photography Forum and on Photrio, please only respond in one place so I don't double-count.