PDA

View Full Version : Idiot question: What's a flange, why is it important?



sully75
14-Oct-2010, 14:52
Is it the thing that you screw the lens into so it sits on the lensboard?

Thanks
Paul

Dan Fromm
14-Oct-2010, 14:55
http://www.skgrimes.com/adapter/index.htm

Sirius Glass
14-Oct-2010, 15:16
Yes, Paul and without it, it is hard to mount a lens on a lens board in a reliable and yet removable manner without damaging the lens.

Steve

Louis Pacilla
14-Oct-2010, 16:10
Hi Paul

It can drive the asking price way down if missing. Particularly on Large lenses. The bigger the lens the harder to mount without a flange. To have a large flange made can run $200-$400 & that's if you can find a small local machine shop that can cut & thread a large flange. So always try & get a flange with big lenses.:)

Peace
Louis

Sirius Glass
14-Oct-2010, 16:35
Adding to what Louis said, some flanges are easy to find, but the flanges that were not popular can become downright impossible to find. I have two enlarger lenses that have a popular "standard" thread and if I need to I would have not problem finding a flange to work. The third lens although fairly new, is really hard to find a flange that works. I was lucky that it had the flange, which did not have much contact area and was in fair shape, but it was still attached. So I did not have a problem.

If you found a lens that you wanted to use on one of your LF cameras, do you think another photographer would sell the only flange he had from one of his lenses?

Steve

Jim Galli
14-Oct-2010, 17:50
It's not important, and I've got half a dozen lenses to sell you. :D:D

RichardRitter
15-Oct-2010, 04:42
There are ways of mounting a lens with out a flange. I have seem then all.
1. Epoxy two types the liquid that will glue the aperture ring fast. Or the paste type your can get the lens to stick to the board and work. Will make removing a bit hard.

2. If the board is metal just get the soldering gun and soldered the shutter to the board.

3. duck tape.

4. Electric tape not as good.

5. Just put the shutter through the hole in the board and warp wire around it.

6. Chewing gun.

Nathan Smith
15-Oct-2010, 06:20
One more that I like: hot glue - you can remove it without harming the lens or threads later

But I think it's probably best if the lens is already pretty secure - like threaded into the wood of a tight board.


There are ways of mounting a lens with out a flange. I have seem then all.
1. Epoxy two types the liquid that will glue the aperture ring fast. Or the paste type your can get the lens to stick to the board and work. Will make removing a bit hard.

2. If the board is metal just get the soldering gun and soldered the shutter to the board.

3. duck tape.

4. Electric tape not as good.

5. Just put the shutter through the hole in the board and warp wire around it.

6. Chewing gun.

Kevin Crisp
15-Oct-2010, 06:22
On thicker metal lens boards like Canham's you can thread the hole in the board, avoiding a retaining ring or flange.

rjmeyer314
15-Oct-2010, 06:23
I have managed to mount several lenses to homemade wooden lensboards without a flange. The trick is in adjusting a "fly cutter", an adjustable hole drill, to cut just the right size hole so that the threads on the lens will grab the wood. It's a good idea to have a lot of scrap wood because it's usually necessary to try several times before you get it just right.

Fotoguy20d
15-Oct-2010, 11:39
There are ways of mounting a lens with out a flange. I have seem then all.
1. Epoxy two types the liquid that will glue the aperture ring fast. Or the paste type your can get the lens to stick to the board and work. Will make removing a bit hard.

2. If the board is metal just get the soldering gun and soldered the shutter to the board.

3. duck tape.

4. Electric tape not as good.

5. Just put the shutter through the hole in the board and warp wire around it.

6. Chewing gun.

I've got more than my fair share of lenses without rings. There are good and bad points to all of Richard's suggestions. A bit tongue in cheek:

1. Ever seen a shutter with glue in the works?
2. Cold solder joint. Or, if you heat it up enough, you'll get the lubricant flowing nicely.
3. Glue residue
4. 10 rolls for $4 at Harbor Freight. And, it's light tight. I like this one and use it often.
5. Or, get a hose clamp at home depot and do the same thing, preferrably with a bit of black rubber gasket material to protect the threads
6. no comment
7. with old brass lenses, I have boards with around a 3" hole in them. I wrap some rubber material around the barrel and jam the lens in so its centered (for wight balance). works well, except the one time I put a speed down on its back and had a big gundlach petzval slide out and crash into the GG (strangely, the fresnel was unharmed).
8. Find a ring that's close - as long as a thread or a bit more catches, you might be alright. don't force it or you'll cross thread and damage something.

Dan

ki6mf
16-Oct-2010, 15:53
A well made flange centers the lens barrel in the center of the bored hole of your lens board. It also helps keep out light fro coming in around the lens barrel.

Drew Bedo
16-Oct-2010, 18:11
There are only three types of flange:

1. Too large.
2. Too small.
3. Wrong pitch.

Louis Pacilla
16-Oct-2010, 18:49
There are only three types of flange:

1. Too large.
2. Too small.
3. Wrong pitch.


Ain't that the truth.:(

Hovmod
18-Oct-2010, 04:12
I just won a Petzval on the bay and was thinking about how to make something. In my mind I see a piece of old metal with a perfect fit, but I'll probably end up duct taping it to a piece of plywood :)