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  1. #41

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    Precision pro enlargers have certainly been made! They just cost fifty or even a hundred times more
    at the time than the typical Beseler or Omega. Today's aluminum extrusions and CNC-cut plate stock
    are no match for old-school machined die-castings and solid alloys. You'll never see that kind of
    quality again; nor will many labs be interested in spending 75K or more on a new enlarger! I could
    easily spend 50K on a state-of-the-art colorhead alone - and that's just the cost of the materials and components (but I obviously never will). For now I'd just like more time to enjoy the enlargers
    I already have built!

  2. #42

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    A possible solution would be to utilize a helical focusing mount combined with threaded lens cones to ensure that the lens and film stages are always in perfect alignment. From there, just add X- and Y-axis adjustments to the entire head assembly so that it could be aligned to the baseboard. Slap on a VC LED hybrid light source and mount the whole head to a strong column with geared height adjustment, brace it to the wall, and call it a day. Ideal construction would be a lightweight head and a rigid column attached to an MDF or ABS baseboard (for dimensional stability and precision of machining) to reduce pendulum vibration as much as possible.

    Or can't someone please just make a new Graflarger back with LED's?
    My real name is Patrick, not Joe. Long Story.

  3. #43

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    Sounds like ya wanna build a doghouse there, using scraps behind some Home Depot, Capn Joe, not anything precise. Warp-free those things definitely are not. Even heavy Garolite phenolic will warp
    if not properly countertensioned. What Durst did in the old days was really clever and fancy: they
    made the baseboard out of matched lumber-core strips, clad them front and back with formica, then
    dadoed in a precision bronze strip diagonal in the backside to counter-pull any temp-induced warp
    on the upper, replete with precise little adjustment pins to reset the tension - and that didn't work
    either !! The "baseboard" on my 8x10 color enlarger was salvaged off a 22-ft long process camera.
    It's a machined steel vac easel with a full set of registration pins. I added an adjustable masking frame. It won't warp. In fact, I can stand on the thing. But it weighs about 400 lbs.

  4. #44

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    Drew,

    Nothing so particularly crude as a dog house, and certainly not a part on the thing from

    Now that I think of it, the plate bases used on hand lithography press beds might be of the right sort of design, as they have to absolutely flat, perfectly smooth, and free from warp after repeated exposure to extremely high pressures. At my alma matter (which I still do some technical consulting for), we'd have them custom ordered to spec, made from some sort of fiber-reinforced resinous plastic. Similar idea to Garolite, but with a much more visible reinforcement weave. Dense as hell, and they get the job done. Only time they get retired is when some idiot comes along and thinks they know how to lift and maneuver that sort of load, then it inevitably hits the floor and chips. They've started replacing them with aluminum, so that when (not if!) they get dropped, the dents can just be filed away.

    Agreed, creating a flat plane that is completely free of warping is a very difficult task. Perhaps a different solution would be to make the baseboard from some nice wood laminate, and couple it to a vacuum easel with some sort of leveling mount. At that point, any deviation from perfect flatness should be inconsequential in terms of the optical system.

    Speaking of lithography, another potential base material could be stone. Couple the column to a metal leveling base like the Durst L1000s and then put a slab of stone on top of that. Weighs the whole thing down, good dimensional stability, easy to come by. Might have a winner.
    My real name is Patrick, not Joe. Long Story.

  5. #45

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    Stone it is! My next baseboard for my Leica Ic which has suffered termite damage will be granite I think.

  6. #46
    Greg Davis's Avatar
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    Quote Originally Posted by emerson531 View Post
    I am surprised no one has mentioned DeVere enlargers.

    They have very precise and intuitively obvious adjustments for the negative , Lens Stage and Baseboard.
    I love my DeVere 5108. It is very easy to align precisely in all three stages. It is also rock solid when bolted to the wall. One improvement they could have made is larger lens boards. It uses the same board as the smaller 4x5 version, which is just barely big enough for a 300mm Schneider Componon-S, and definitely too small for a 360mm lens, a 300mm El Nikkor, or even a 210 APO El Nikkor if you have one.
    www.gregorytdavis.com

    Did millions of people suddenly disappear? This may have an answer.

    "No one knows that day or hour, not even the angels in heaven, nor the Son, but only the Father." -Matthew 24:36

  7. #47

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    Cap'n Joe: before this current era of composites, there was a product called Benelex which weighed
    a ton and had to be machined with diamond. It ate carbide alive, but was dimensionally stable, and
    was ridiculously impact resistant, but not resistant to strong solvents. I still have a film punch made
    on it. What I did for my enlarger column is take a highly stable kind of strand structural beam material, with phenolic glue throughout, squared it off on our 600V 22" table saw here, pickled the
    whole thing with penetrating epoxy, then fully laminated it with black formica and extruded edging.
    I did this both for sheer support (I live just a few blocks from the infamous Hayward fault), as well
    as for precision. I can fine focus a neg up to say 30X40, leave it in there all winter, come back,
    and the focus will still be perfect.

  8. #48

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    I knew I liked you for a reason, Drew Wiley.
    My real name is Patrick, not Joe. Long Story.

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