Pentax 6X7 Film Advance Question

Beevo

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I have a recently acquired 6X7 MLU I am having issues with. I had a 6X7 system many years ago and shot tons of film so for the most part am used to the camera and its peculiarities.

When loading this body pulling out the leader to attach to the take-up spool is is very difficult. Once the tab is on the spool advancing with the lever is VERY difficult, to the point I have only done this once, falling back on pulling the leader out by hand to the mark.

Now, once the back is closed the advance is light and smooth.

Thoughts?

Bill
 

skylight1b

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It took me a few reads to understand what you're saying. So the wind lever is very stiff when the back is open?

I don't really know what the inner mechanisms are like but I know the Pentax behaves differently with and without film in it. It would make sense that something engages once loaded and changes the function of the lever, but I don't understand why it would be so stiff otherwise.

Edited: I see I misunderstood the problem. The feeding side should definitely not be that stiff.
 
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Beevo

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If I had to pull on the leader any harder, I would come close to tearing the paper...
 

MattKing

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Could the problem be originating at the feed spool side?
 
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Beevo

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I am absolutely sure it is, trying to divine why...

As well as why it goes away when the back is closed. Has to be some connection.
 

Pieter12

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I assume the pressure plate is set for 120 film, that would only affect the winding with the back closed. There is a warning in the manual to never turn the spools in the opposite direction, could that have been done and caused some damage?

 
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Beevo

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You assumed correct on the pressure plate. I can't vouch for how the camera was operated prior to my acquisition. I am aware of that admonishment as well as others concerning the camera.

Winding is smooth and very easy with the back closed.
 

OAPOli

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That is strange. The feed spool tab is just floating as far as I'm aware. No clutch, no connection to the advance mechanism.

Can you try just putting a feed spool and turning it by hand?
 
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Beevo

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I plan to compile suggestions and when the roll of film in the camera has been used up and removed experimentation will commence. I have save a pair of leaders to use as a "test" roll.
 

choiliefan

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This is a know problem with these cameras.
I fixed mine by watching a youtube video.
This may be the one:
 
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Beevo

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That (sorta painful to watch) video alludes to it getting hard to advance after a number of frames have been shot (unless I am missing something)

The only time mine is stiff (excessive tension on the supply spool) is when the back is open. Once the back is closed the advance is always smooth and easy. I will try to watch the video again later when I can spend more time. Thanks for the link.
 

MattKing

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Is the open back somehow contacting the feed spool?
 
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Beevo

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Not sure how this could be an issue, the back attaches on the opposite end.
 

loccdor

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I don't know if this will fix your problem, but check that you are rotating the rings under the spools on the bottom of the camera in the appropriate direction.
 

Taylor Nankervis

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With the exception of a small spring to allow downward movement of the pin when inserting film, the left side chamber spool pins are free-moving — no clutches, cogs or pawls etc., other than the locking tab that must be aligned correctly to close flush with the clasp body once a roll of film has been installed. I suspect there is something like dirt or gunk built up that is restricting the free movement of the pin. A check should also be made that the pin is not bent (there are a few ex-professional 6x7/67 bodies that have bent pins in both sides of the chamber, indicating quite brutal and careless treatment).

Other parts within the 6x7 / 67 chamber must be avoided, very especially the film counter roller, left of the take-up spool; this has two extremely fine internal worm-springs and deliberate reversing of the roller will pretty much "reverse wind" these frail springs (I doubt very much they, like so many other intricate parts, are available as OEM replacements!).
 
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Beevo

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Beevo said:
I plan to compile suggestions and when the roll of film in the camera has been used up and removed experimentation will commence. I have save a pair of leaders to use as a "test" roll.
Click to expand...
OK, the camera is fixed...

Before I packed it up to send to Tennessee for servicing I decided to see if there was anything that I could do to free up the shaft/flange where the top end of the film spool fits. I have a magic bottle of some high grade watch oil (you are wincing already, right?) and with the needle tip applied the most sparing drop of oil that I could. I then used a Q-tip to blot any possible excess from the area.

Miraculously the problem went away and immediately!

The camera is a joy to use once more.
 

Taylor Nankervis

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Beevo said:
(you are wincing already, right?)
Click to expand...

Yes I am!

Evaporative carrier dry lube (PTFR) should only be used on any of the 6x7 / 67 internal parts, definitely nothing like machine oil which will leech its way around no matter how small the drop.
 
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Beevo

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I think you are overestimating the amount applied. Basically moisten a swab and wipe the surface.
 

randyB

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To whom and where is the repair place in Tennessee? I was unaware of any repair facility in the state.
 
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Beevo

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Home-Pentaxs

pentaxs.com

He just went through my TTL Prism that had a loose view port for the meter needle window.

Lee has a long history with the Pentax brand and my limited dealings with him have been spectacular. $50 including return shipping.
 
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