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adamc
28-Jan-2010, 10:40
Hey everyone,
Please forgive the novice questions, this is new to me...

I have a Speed Graphic that I love, but am thinking I'd like to try something new with it. I want to put the focal plane shutter to use, and I'm thinking I'd like to pick up a barrel lens for it. I love working with old equipment, and the look (and price) of these old lenses have attracted my attention.

I think what I'll need is an aluminum Speed Graphic lensboard (which will have to be re-drilled to fit the lens), a barrel lens with an aperature, and some way to put them together - is that what the flange is for? I've seen some with mounting rings. Should I avoid lenses without a flange or mounting ring?
When I have the pieces, I'll drill out the hole in the lensboard so the lens fits snug and fasten them together somehow...do drill holes and bolt them together? Do I seal up the seams with anything?

I'm sure I could figure all this out if I had the items sitting on my workbench in front of me, however trying to figure it out what to buy and how to piece them together by looking at web pics has left me with more questions than answers.


Thanks in advanced, you guys are great!
Adam

Bill_1856
28-Jan-2010, 11:54
You got it right. Just put a piece of felt between the lens and the lensboard (usually behind it to avoid any light leak. A flange attaches to the board by screws, then the lens is screwed into the flange, whereas a mounting ring screws onto the back of the lens and holds the lens on by friction. The 10" Tele-Raptar is a particularly nice lens for a Speed.

Dan Fromm
28-Jan-2010, 11:56
Many are the ways.

If the lens is threaded externally at the back and will clear the lens throat then a flange (use if the board can't be clamped between a retaining ring and the lens) or a retaining ring or flange (if it can be clamped) will do it. If you don't have a flange or retaining ring and need one, www.skgrimes.com will make one to fit the lens. They'll bore the board too if that's needed.

If the lens won't pass through the lens throat and is threaded externally at the rear, a cup-shaped adapter that sits in front of the board and is held to it by a retaining ring will do it. I've had skgrimes make some of these.

If the lens won't pass through the lens throat and is threaded internally at the rear, a stepped bushing may do. I have several of these made by guess who.

If the lens isn't threaded at the rear, a clamp attached to the board might do. I have one lens held to its board this way. Same supplier.

Depending on the situation (lens, board, ...), how brave you are, and how handy you are, a piece of PVC pipe, globs of epoxy putty, ... might do. All of these have been used.

Chauncey Walden
28-Jan-2010, 13:58
Since I have more than a dozen barrel lenses for my Speed, long ago I made an adapter so that I would only have to have one aluminum board. I enlarged the hole considerably and epoxied 4 machine screws in from the back in the corners. Then I just made a pile of blank hobby shop plywood boards with oversized holes in the corners to slip over the screws. Small wingnuts hold the boards together. Whenever I get a new lens, I just cut a hole to fit it (jig saw, jewelers saw, or expansion bit) and do whatever I need to mount it - whether it is retaining ring, flange, or hot glue. If I was starting from scratch, I would now make an angle bracket across the bottom of the aluminum board to hold the plywood board and use two pivoting window screen holders at the top corners to lock it in place which would be much quicker to change and preclude losing a wingnut.

adamc
28-Jan-2010, 16:03
Cool, thanks guys.
It sounds like what I was going to do anyways...doesn't have to be pretty or perfect, just make it light tight and functional.
I do like the idea of the 'universal' aluminum board, I might have to sketch up some plans.

Thanks again,
Adam