Share your favorites on Show & Tell

Duff Mfg Railroad Car Sill Straightener 1925

In Railroadiana > Show & Tell and Tools and Hardware > Show & Tell.
Railroadiana261 of 1311Who Remembers Railpax?Amtrak thermometer
Love it
Like it

mcgyver80mcgyver80 loves this.
AnythingObscureAnythingObscure loves this.
yougottahavestuffyougottahavestuff loves this.
blunderbuss2blunderbuss2 loves this.
See 2 more
Add to collection

    Please create an account, or Log in here

    If you don't have an account, create one here.

    Create a Show & TellReport as inappropriate

    Posted 5 years ago

    (4 items)

    What is it? Its really heavy, big, cool. Thanks for your help! My imagination tells me it could be used to tighten tracks on a tank? All I can find about Duff relates to jacks and this seems to be an antijack.

    Similar models made by simplex.

    Modern versions are advertised as useful tools for welding shops, likely to hold material together while welding or spread parts?

    Update 11/25/18: it is a sill straightener patented by Duff Manufacturing in 1923-1925. Google Patents: Sill Straightener.

    Mystery Solved
    See all
    Railroad Crossbuck Crossing Large Prismatic 23
    Railroad Crossbuck Crossing Large P...
    Antique Kerosene Brasstop Bellbottom Railroad Lantern CRR Concord ? Blue Globe
    Antique Kerosene Brasstop Bellbotto...
    1920s Travel by Train Colorado Rockies Vintage Style Travel Poster - 16x24
    1920s Travel by Train Colorado Rock...
    B&O RR Vulcan railroad lantern w/ clear cast ext base Macbeth globe
    B&O RR Vulcan railroad lantern w/ c...
    Railroad Crossbuck Crossing Large Prismatic 23
    Railroad Crossbuck Crossing Large P...
    See all


    1. Jacobwaco, 5 years ago
      Thank you bobby725 for the info, I never imagined it would be related to logging. Do you have a guess as to what time period it is from? Thanks again for taking the time to help.
    2. UncleRon UncleRon, 5 years ago
      They make such a thing to join long sections of pipe which need to be tightened together or slid into a coupling. Clamps are put around the sections to be joined and the tool is hooked onto specially designed surfaces on the clamps and cranked together.
      The moveable parts can also be reversed on the threaded rod to work in the opposite direction.
    3. Jacobwaco, 5 years ago
      Thank you UncleRon! Do you imagine it has a specific tool name? Thanks for sharing your knowledge.
    4. UncleRon UncleRon, 5 years ago
      I think it's Bob. No, seriously, I have no idea. If you haunt the plumbing /construction tool sites you may find it. If my guess is correct I think it would be for fairly large pipe - say three or four inches, or more.
    5. Jacobwaco, 5 years ago
      Haha, thanks UncleRon. I'll update here if I find more information.
    6. Jacobwaco, 5 years ago
      I have concluded that the official term is Push Pull Screw Jack. I have found models made by Simplex that appear to be more recent. I cannot yet locate any reference of this model by Duff. I found a patent that is attributed to Duff Norton around 1955 for a more advanced version based on the same principle.

      I assume this is pre 1955.

      Will update as I learn more!
    7. Jacobwaco, 3 years ago
      I have solved the mystery through patent research. Thank you everyone for your advice and interest.

    Want to post a comment?

    Create an account or login in order to post a comment.