Cambo TWR 54 - 4x5 Twin Lens Reflex (like Gowlandflex) Question...

[Christopher Nisperos]

After seeing the above post from Aesthetique, I re-doubled my efforts and —EUREKA!— I've (re-) found the original cam plans that René Rook, of Cambo, kindly sent me years ago for the for the 150mm and 210mm focal lengths (I don't remember receiving a plan for the 270mm cam, but if I re-discover one, I'll post it here, too).

NOTE: My scanner is out of order, so I quickly took simple photos of these drawings which —until I have a chance to scan properly— I hope will be sharp enough to be useful!

Apologies to all my co-TWR users who have 're-invented the wheel' in retro-engineering these cams: years ago, when I first searched for the cams, myself, there wasn't the same interest in this camera as there is today, and I had "safely" filed the drawings away ... so "safe" that I couldn't find them, myself!

I hope this helps a lot of you.

[DrTang]

I'd be interested in the close focusing 210 cam

[EdSawyer]

Wow cool - thanks for posting those. Would be great if we can get real scans too!

Thanks for sharing and for the efforts on parts of both folks. I would probably be in for a close-focus 210 cam also.

The stock 150 cam I found too limiting for close-focus so made my own more than twice as long and it allows nicer closeups.

[Aesthetique]

OK thanks Chris.... I have spent 2 hours recalculating and redrafting the 210mm cam and tweaked the 270mm cam on the basis of the drawing.

Ed and Dr.Tang, in brass I think I can supply them at about £30 each....

[Christopher Nisperos]

@Ed and Aesthetique: You're welcome! .. and I repeat that the real credit goes to René Rook at Cambo in Holland who apparently had to go through some boxes in their basement, or something .. I harassed the poor guy for more than a year to get these.

Currently, if I understand correctly, our little group of TWR-54 fanatics have made the cam range look like this:
150mm standard
150mm close focus*
210mm standard
210mm close focus*
270mm standard
270mm close focus*
*custom made

Your corrections or additions are welcome (wasn't there a 180mm version somewhere?), as it seems probable that future Cambo TWR-54 users will end up here for information . . . and why not, in fact, make this thread a repository for other cam drawings? (I'll try to get cleaner scans posted here as soon as I can).

[Aesthetique]

180mm and 240mm can be interpolated from the 150mm, 210mm and 270mm; understanding of course that the 270mm is for a telephoto design with a reduced back focus. My 180mm and 240mm musings will need to be tweaked, as Christopher's publication of the 210mm cam has changed my curve for the closest focus point (where the pins are 9mm apart), which then gives you the cam slot angle.
All my cam designs have at least some "close focus" beyond the end of parallax correction, partially to allow closer focus, but mainly so that the pin is less likely to be slammed into the end of the slot as the 40 year old plastic holding the pin is now very brittle.

270mm close focus cam.... add it to your list Christopher!

[Aesthetique]

Preliminary 180mm close focus cam

[Aesthetique]

I have placed an order for 210mm and 270mm cams with the laser cutting engineering firm. Work starts on Monday morning..... I am excited!

[Christopher Nisperos]

180mm and 240mm can be interpolated from the 150mm, 210mm and 270mm;...... 270mm close focus cam.... add it to your list Christopher!

Done, Aesthetique, giving you credit in the editing reason comments. Let us know how the laser-cut cams work out ... and how much they cost!

Perhaps the engineering company will keep the drawings on hand for future orders? PS: It just occurs to me ... Why didn't you see if anyone in the forum wanted to order at the same time as you? Wouldn't that have been a bit cheaper for each buyer?

[EdSawyer]

I will probably be up for one or more. Since they are laser cut chances are the per-piece price doesn't decrease all that much in volume? Hard to guess