Linhof Technika III rangefinder focus binding with 90mm cam and bed dropped

[DLee]

Not sure where to post this but I'm wondering if anyone else has had this problem on the Linhof Technika.

When I use the 90mm lens on my Technika III the bed must be dropped. For some reason, when I drop the bed the focus track starts binding when returning to infinity and it gets progressively worse with each in and out movement. It becomes tight to the point where I would not be able to get the track back to infinity without really putting pressure on the rack (which I would never do of course).

Through a process of elimination I've determined that the problem seems to stem from the 90mm cam running on either the support bar (unlikely) or the cam follower wheel (I don't know if it's supposed to actually rotate or remain stationary...) that moves in and out with the track pushing the cam driving the rangefinder.

I've talked to Nippon Photo Clinic and will probably take it in. But if anyone knows if the roller should roll... and if I can take it out and lube it or loosen it (?)... or if it's a know problem for the cam to bind in this manner, I'd love to know.

Right now I can raise the bed and easily crank the rack back to infinity without any binding or tension, then lower it again into place for the 90. But this isn't exactly the way I want to work with the camera in handheld scenarios.

Any insight to this would be great.

Thanks,

d

[Bob Salomon]

You do remove the cam before dropping or raising the bed to prevent bending it?

[DLee]

You do remove the cam before dropping or raising the bed to prevent bending it?

No I don't. The hinge of the cam holder is right at the gate. So if the rack is all the way in (at infinity) there's nothing I can see that would bend the cam while opening or closing. Is that what you mean? Same with dropping the bed for 90mm setup.

I checked the cam against a straight edge and it has the slightest of slight bends - putting the bend upside down on the straight edge there might be enough room to slide a couple sheets of paper under the elevated center.

Can you expand on when to remove cams? I've never heard of this.

Thanks,

d

[Bob Salomon]

No I don't. The hinge of the cam holder is right at the gate. So if the rack is all the way in (at infinity) there's nothing I can see that would bend the cam while opening or closing. Is that what you mean? Same with dropping the bed for 90mm setup.

I checked the cam against a straight edge and it has the slightest of slight bends - putting the bend upside down on the straight edge there might be enough room to slide a couple sheets of paper under the elevated center.

Can you expand on when to remove cams? I've never heard of this.

Thanks,

d

You’ve never read the instruction manual either. You always remove the cam when dropping or raising the camera bend so you don’t bend the cam.

[Corran]

What lens board is your 90mm on?

You shouldn't have to drop the bed to use the 90mm. It should be in a recessed board so that it works normally on the straight bed - otherwise the cam simply won't work (and binds as you have seen).

I have a Linhof Tech III and it has a 90mm f/6.8 Angulon on a slightly recessed board and the cam/rangefinder works perfectly without dropping the bed.

[DLee]

You’ve never read the instruction manual either. You always remove the cam when dropping or raising the camera bend so you don’t bend the cam.

Bob I know you are the Linhof Guru here but I am going to disagree. First of all I have read the instructions several times and unless it's hidden in the flash photography or in the commercial focusing section there is NO mention of removing the cam at any point in using the wide angle lens or dropping the front lens bed.

https://www.butkus.org/chinon/linhof/linhof_technika_iii-guide/linhof_technika_iii-guide.htm

I really don't understand why the cam would be removed for dropping the bed, there is nothing in the way of the cam as the bed is dropped. If there was, the rack would not be able to be retracted back to infinity without manually pushing down on the cam so it clears the rack... and that is certainly not the case. Is this something that might have been in instruction manuals for later models?

Not trying to be disrespectful here, just trying to understand this unusual operation. Can you expand on this at all?

Thank you,

Dennis

[DLee]

Bob I know you are the Linhof Guru here but I am going to disagree. First of all I have read the instructions several times and unless it's hidden in the flash photography or in the commercial focusing section there is NO mention of removing the cam at any point in using the wide angle lens or dropping the front lens bed.

https://www.butkus.org/chinon/linhof/linhof_technika_iii-guide/linhof_technika_iii-guide.htm

I really don't understand why the cam would be removed for dropping the bed, there is nothing in the way of the cam as the bed is dropped. If there was, the rack would not be able to be retracted back to infinity without manually pushing down on the cam so it clears the rack... and that is certainly not the case. Is this something that might have been in instruction manuals for later models?

Not trying to be disrespectful here, just trying to understand this unusual operation. Can you expand on this at all?

Thank you,

Dennis

Actually Bob, I just tried doing this operation as you describe and it's not possible. The rack needs to be pulled back and the lens standard pulled forward (onto the bed) before dropping the bed... so it's not possible to even get to the cam when dropping the bed.

Are we talking about the same thing or have I missed something here. Looking forward to hearing from you.

Thanks again,

Dennis

[DLee]

What lens board is your 90mm on?

You shouldn't have to drop the bed to use the 90mm. It should be in a recessed board so that it works normally on the straight bed - otherwise the cam simply won't work (and binds as you have seen).

I have a Linhof Tech III and it has a 90mm f/6.8 Angulon on a slightly recessed board and the cam/rangefinder works perfectly without dropping the bed.

I have the exact same setup. My camera, with matching serial numbers for cam, camera and lens, is actually set up for the bed being in dropped position. I just checked and the rangefinder focus is way off if the bed is NOT in dropped position. Focus is dead on when dropped and as mentioned the cam must be inserted before dropping the bed. This is an original Linhof setup you can tell by the quality (it looks to me). Check the manual on pages 26 & 27, it says to drop the bed when using the 90mm lens.

I used the 90, cam, and drop bed all the time years ago and never had a problem. She's been sitting idle for a few years now and this problem has cropped up.

https://www.butkus.org/chinon/linhof/linhof_technika_iii-guide/linhof_technika_iii-guide.htm

Cheers,

Dennis

[LabRat]

I leave a 90mm cam on my Tek III all the time (I don't use the RF at all)... When the bed slide is all the way close to body, cam is about centered and bed can be dropped safely...

The only scenario where my cam is removed is there is a modification done to my camera where the top of the bed struts have the tip of stops filled away so bed struts can slip past the stops to be able to drop bed completely if needed for UWA work... The normal spring action keeps the stops working normally, but if you press struts completely in while operating, they will release... Only takes removal of about 1mm of inside stop tip with a file while removed from camera (do one at a time to not change bed alignment)...

Steve K

[Corran]

I'll have to dig my III out and look again. I seem to remember it not dropping while using the RF. Maybe I am misremembering, but the camera did go through some evolution over its manufacturing history.

[DLee]

Corran, Yeah I was wondering if we might have different models. Bob told me mine was made in 1956.

[Embdude]

This might help, the RF cams should have a bend in them. This image is from a IV cam but it has a similar bent construction to a III cam... 224789

[Embdude]

Also be sure you are adjusting the rails back a notch.

Here is the information/manual for your Late model Technika III. Hopefully it will clear things up a little.
It mentions the RF cam is used normally with the first and second notch of the bed drop but must be removed to prevent damage to use the third notch. In my experience the later Technika III's usually only had 2 notches, while the Early model III's usually had 3. I have seen Late models with 3 but it is not common.

https://drive.google.com/file/d/13X89pvSY3gu910iZer_ijwDm3sQBCiwr/view?usp=sharing

224790

[DLee]

Also be sure you are adjusting the rails back a notch.

Here is the information/manual for your Late model Technika III. Hopefully it will clear things up a little.
It mentions the RF cam is used normally with the first and second notch of the bed drop but must be removed to prevent damage to use the third notch. In my experience the later Technika III's usually only had 2 notches, while the Early model III's usually had 3. I have seen Late models with 3 but it is not common.

https://drive.google.com/file/d/13X89pvSY3gu910iZer_ijwDm3sQBCiwr/view?usp=sharing

224790

Embdude, you had my hopes up there for a moment with the 'third notch' description for the drop down bed. But I soon remembered and then verified that my drop down arms have only two notches. My instructions for the III are near identical to what you posted here.

I actually do have three notches in my focusing rails; for the 90, 150, and a 10" Kodak Ektar. My 90 cam looks just like yours above and it has matching numbers for camera and lens on it.

So, yeah, I pull the lens out, drop the bed, tilt the lens and slide the track back. Focus comparison between the rangefinder and the focusing screen is accurate so I'm sure I'm doing everything correct. I'm at the point where I'll play with the camera and make some pictures and if I want to keep using it for portraits or my documentary work I'll take it to Nippon Photo Clinic and talk to them about it and maybe bite the bullet on a CLA.

Something is causing friction on the cam which starts it binding after a few in and out movements of the focusing rack. I think it's the cam roller because it doesn't actually roll. But I'm not sure it's supposed to and I'm not going to mess with it as it's a major component in the focusing system. Who knows, maybe it's this frigid weather?

Thanks for the interest and continued help in trying to solve this. It's appreciated.

Dennis

[Embdude]

Sounds like you are setting it properly... I have a late model Technika III as well and the part that is screwed on at the rear of the rail which makes contact with the cam is stationary and does not roll.
The cam simply rides along it so I don't see how it could create binding unless it is happening somewhere downstream in the linkage with the rangefinder... Or perhaps it is something on the standard that is binding on something.
I suggest trying 2 things...
1. Do not pull out the standard, just leave the on the perch. do everything else. Drop the bed to the second notch, slide the rail back and see if you get the same problem. 2. With the camera in the current positions as step 1 roll the rails forward beyond the cam and move the cam with your fingers and see if it is binding on anything internally...

[Bessa72]

my Tech III also has a 90mm cam in it, it gives no probs dropping the bed into the first notch. You always have to push back the inner rail back towards the inner sitting rail in the case.
on my Tech III I can see that the black paint unterneath the cam has been worn off, I think its worth a try to do taht on yours..maybe it is just about a fraction of a mm thats causing this.