Jump to content

AON

NRG Member
  • Posts

    2,596
  • Joined

  • Last visited

Posts posted by AON

  1. Mark

    If the curve is one radius:

    1. calculate the circumference of the circle (360°)  at Circumference = π × diameter = 2 × π × radius.  where π = 3.1416

    2. determine the portion of the arc of the radius in degrees (a portion of the 360°)

    3. the flat length is the ratio of the two (#2 above/360°) times the circumference of the circle (#1 above).

     

    To determine the location at lengths along the arc of the circle simply break it down to smaller ratios of portions of the arc.

    Then multiply these smaller ratios by the circumference and you have the flat length location for the smaller segment along the arc.

     

    If the curve is comprised of a number of conjoined but different size radii, break them down, and do the steps above for each.

     

    I hope I have explained this clearly.  If not I am certain I have an old draughting book here with an example that I might scan and send you.

    Alan

  2. Regarding the rigging of the bowsprit, jib boom and yards.  I had had a question about the rigging of the Jib Guy Pendant.  It originates from the head of the jib boom and needs to run over top of the spritsail-topsail yard to run through a thimble on the spritsail yard.  I predicted with my drawings that this pendant would run below the spritsail-topsail yard to reach the thimble which would mean it would then pass through the spritsail-topsail canvas.  Search as I might I could find no image or statement to describe how the line could be taut and still pass over top of the yard.  The logical solution was that the spritsail-topsail yard  needed to drop, suspend lower below the jib boom to create the required clearance.  My drawings showed it would need to hang a minimum of 24 inches (61 cm) below the jib boom.  Two feet did not seem to be unreasonable.

     

    While reviewing a video post in HMS Bellona 1760 by SJ Sloane, posted by Hubac's Historian , posting #1670, showing how a steering wheel works on HMS Victory I spotted the rigging of the Jib Guy Pendant.  It passed over the yard but is loose. I captured a screen shot of the image.

     

    If anyone else should ever ponder on so small a detail, this may be the only image you will find.

    Untitled.jpg

×
×
  • Create New...