Adjusting tabs to hold lens board on Chamonix 45 N-2

[Kiwi7475]

This seems surprising as the Luland boards are not particularly thick. I mean, actual linhof brand boards are a few tenths of a mm thicker than the Luland.

How far off are you in thickness between a Luland that doesn’t fit, and another lens board that fits without force? Do you have a caliper to measure both? That can also guide whether adjusting the screws has hope.

[Kiwi7475]

Another option if you don’t want to file and repaint, would be to ask Luland for a custom lensboard version that is sufficiently thinner. They do custom stuff like that. They might even cost the same or not much more since it’s a simple thickness adjustment.

If you know what thickness works and you don’t have a lot of lenses, getting new boards of the right thickness maybe be the easiest way — not as cheap as filing what you have, but less work. But you need to measure accurately what thickness works and tell them that.

[Bernard Kelly]

Another excellent suggestion. It never occurred to me that Luland might alter the thickness to suit. I've ordered calipers and will presumably have a better idea of how much my boards are off in a few days.

To answer your question, no, I don't have a board that fits perfectly. So I can't compare.

[Kiwi7475]

Well, then maybe take a sacrificial lensboard, file it down until it fits, snuggly but not too hard, measure the new thickness (right where the camera tabs are), subtract a slight bit of margin for fab tolerances (like 0.25mm or so), and talk to Luland. You could start with ordering one or two to make sure everything’s good and then buying the rest.

[Bernard Kelly]

Thanks, everyone, for your suggestions. I'll report back in a little while when I have calipers (and file) in hand.

[Bernice Loui]

Linhof Technika type lens boards have precision machined registration pads/bars on the rear and one registration bar front top. These are precise/accurate in their location and thickness regardless of the body thickness of the lens board. When the front standard mounting for Linhof Technika type lens boards are properly implemented, the lens board rest and is held in place at these registration points.


Linhof Recessed lens board front registration bar.


Linhof Recessed lens board back registration pads/bar.


Identical registration pads/bar on Luland/Linhof Technika type lens boards.




Location for these registration pads/bar are identical in location. Next set of images illustrates they are within a few 0.001" tolerance from no name generic to OEM Linhof.

What is most likely the cause of this problem has to do with the design of the lens board retainer on the Chamonix 45 N-2 instead of the Linhof Technika type lens boards as they are made/produced to surprisingly consistent tolerances and standards.

The properly solution appears to be, use the OEM lens boards specific to the Chamonix 45 N-2 instead of trying to fit Linhof Technika type lens boards to a camera not specifically designed for them.


Bernice

[Bernice Loui]

Comparison of Linhof, Luland, Toyo and genetic Technika style lens board front registration pad/bar thickness with a micrometer. Typical thickness is 0.090".

Linhof = 0.092"


Luland = 0.090"


Generic = 0.0925"


Toyo = 0.090"



Variation of 0.0025" is insignificant specially for a wood field camera.



Bernice

[Bernice Loui]

Comparison of Linhof, Luland, Toyo and genetic Technika style lens board back registration pad/bar thickness with a micrometer. Typical thickness is 0.086" likely due to board angulation due to micrometer clamping force needed to hold the board being measured in place for the Foot.

Linhof = 0.0885"


Luland = 0.087"


Genric for Technika = 0.084"


Toyo = 0.084"



They are quite consistent in their dimensions, problem here is likely due to the Chamonix 45 N-2 lens board mounting/retaining system not the Linhof style lens board's body thickness.


Bernice

[Kiwi7475]

Comparison of Linhof, Luland, Toyo and genetic Technika style lens board back registration pad/bar thickness with a micrometer. Typical thickness is 0.086" likely due to board angulation due to micrometer clamping force needed to hold the board being measured in place for the Foot.

Linhof = 0.0885"


Luland = 0.087"


Genric for Technika = 0.084"


Toyo = 0.084"



They are quite consistent in their dimensions, problem here is likely due to the Chamonix 45 N-2 lens board mounting/retaining system not the Linhof style lens board's body thickness.


Bernice

That’s exactly right — and it’s IMO disappointing that Chamonix’s response is just issuing a warning instead of taking responsibility and replacing the camera. It used Linhof type lensboards and they should fit.

However at the price of Chamonix boards, it’s far more economic to get skinnier boards than — by a factor of ~5.

[Bernice Loui]

Appears the solution to this problem is to use only Chamonix lens boards designed specifically for this camera, Done.

Another "penny wise, pound foolish" issue as the cost savings from using generic Linhof Technika style lens boards could result in floppy lens board/lens to camera causing long list of problems including the very real risk of having the lens fall off the camera... which will incur far greater cost than would be saved by using a non Chamonix lens board.

Lens board attachment and retention to the camera's front standard is basic, if any camera fails to have absolutely secure and positive lens board with lens retention, that camera should be a non-starter, non-owner based on this aspect of the camera alone. There is absolutely zero excuse to design in a iffy-marginal lens board/lens to front standard retention system, zero.


Bernice

That’s exactly right — and it’s IMO disappointing that Chamonix’s response is just issuing a warning instead of taking responsibility and replacing the camera. It used Linhof type lensboards and they should fit.

However at the price of Chamonix boards, it’s far more economic to get skinnier boards than — by a factor of ~5.