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Addams family stairs

  • 1.  Addams family stairs

    Posted 01-24-2019 16:36

    Hello all,

    I just joined the groups and must say it is refreshing that everyone is so willing to help out people who have not been a part of theatre very long.

    I come with a question or questions about casters/wagons and how to calculate the load and how many casters are needed.

    I'm working on the set of The Addams family. I one (two technically) large set pieces that need to be moveable. Two set of stairs. Both with a total run of 14 feet and total Rise of 8foot 6 iniches.

    To move them off stage or course stage I need to make them manageable. For 4-8 Student to move.

    So my questions are? Does anyone have any suggestion as a rule of thumb number of casters for something that weighs in the ballpark of 300-500 lbs and is 14 feet Long , 8 foot 6 inches high and about 4 foot wide.

    Any suggestions?

    Ron Obringer

  • 2.  RE: Addams family stairs

    Posted 01-26-2019 00:49
    Hi Ron

    For a simple explanation, google, "Tributary area."  There are many links out there that show you how to calculate the load on your platform and how it is distributed to each caster.  If it confuses you, hit me back and I will run through it with you.

    On another note, please don;t attach casters directly to the lid.  Make sure the frame transfers the load from the skin to the caster, or your math will be incorrect and your frame will be less than effective.

    All my best!!

    Tracy Nunnally
    NIU - Professor/TD/Area Head
    Vertigo - Owner/System Designer
    ETCP Certified Rigger/Trainer
    DeKalb, Illinois

  • 3.  RE: Addams family stairs

    Posted 01-29-2019 11:37

    Thank you for pointing me in the correct direction. I am still working on this. I guess I need to calculate the psf for this will the assumed weight of 500lb  over a 14x4 wagon. 

    14 foot x 4 foot = 56sft
    500 lb divided by 56 sqft = 8.92pft2 I think that is correct.

    Then figuring out the Tributary area and so on and so forth.

    Let me know if I'm barking up the wrong tree here..

    Thanks Tracy

    Ron Obringer
    North Tonawanda NY

  • 4.  RE: Addams family stairs

    Posted 02-05-2019 17:03
    Thank you for your help Tracy it has been much appreciated.

    Ron Obringer
    North Tonawanda NY

  • 5.  RE: Addams family stairs

    Posted 03-21-2019 13:05
    Edited by Ron Obringer 03-21-2019 13:06
      |   view attached

    Welll we build the stairs. Somewhere in the ballpark of 375lbs each.

    After the proper calculations and buying the 3P20PST casters from Access caster, the stairs moved flawlessly.

    uploading a vidoe of two of the smallest kids i could find to move it. 

    Thanks again Tracy!

    Ron Obringer
    North Tonawanda NY