Beseler Pagemaker35 backlash adjustment

[tkamiya]

I just acquired a Beseler Pringmaker35 in TLC-required condition. What I cannot figure out is how to adjust the annoying backlash in focusing knobs. There's enough of it to blow an image out of focus. Here's what happens...

Put a film in and I raise the bellows
slowly lower the bellows by turning the knob to focus
At this point, the image is in sharp focus
If I touch the knob at this point, it turns slightly without much resistance, perhaps a degree or two. With it, the lens moves about 1mm or two. Just enough to mess up the focus.

Put in other ways, the knob moves the lens as designed but there is a very small (one or two mm worth) turn that has very little resistance, and beyond it, there is a good resistance. The knob turns very lightly for this mm or two. This is enough to mess up my focus.

Is this the nature of this enlarger or is there an adjustment available?

 

[MattKing]

Here is a link to the instruction manual for the Beseler 67 CS enlarger - there may be some similarities in how the focus adjustment functions:

http://www.darkroompro.com/pdf/enlargers/beseler_67cp.pdf

Matt

 

[David A. Goldfarb]

Is there a set screw on the knob? It may just be loose.

 

[tkamiya]

No, the knob itself is tightly coupled to the shaft that it's on.

 

[John Koehrer]

How about a tension adjustment on the focus shaft? Usually it's just a spring holding the shaft in place and
a partial turn will snug it up.

 

[jvo]

no beseler

had the same problem with my omega enlarge - worn parts! replaced and all worked fine!

 

[tkamiya]

I have something to report back.

The cause and the solution was SO simple it's almost embarrassing. If you can picture this - the focusing knob attaches to a rod that goes across the head assembly and friction ring raises and lowers the head. This "rod" is held by two supporting cradle that is hard plastic and springy metal sheet holds the rod in place. It's a lose friction bearing.

ALL I needed was to lubricate this part. A small amount of WD40 (penetrating and lubricating oil) and move it few times. It's very smooth now and backlash is virtually gone. YAY!