Do you have a Proctor D Mast?www.seldenmast.co.uk/

How to tell if you have the Proctor D mast Section

Proctor masts have been the most common in the 505 for some time, with the Proctor "D" having been popular on-and-off for longer than I have been sailing (25 years). Proctor masts are extruded aluminum with an integral sail track, cut-and-welded at the top to produce a taper.

The Proctor "D" section is somewhat "pear" shaped in cross section, with the sides at the back fairly straight, unlike most of the other sections, which are more rounded at the back. Section drawings

     DDD
   D     D
   D     D
    D   D 
     D D 
  <= Sides at back of section are almost straight on "D".
  The "E" is very similar, though slightly smaller in cross section.
 
     BBB 
   B     B
   B     B 
   B     B
    B   B  
     BBB
 
   <= Beta, Epsilon, Stratos and other Proctor sections are more rounded.

Older Proctor masts and boom are typically gold anodized, while a light grey silvery color was normal after the early 1970's.

The "D", "E", Beta, and Beta Minus were common until the mid '70s. More recently, the epsilon in the early '80s, and the Stratos in the very late '80s and early '90s, have been common alternatives to the "D".

The Z-spar, a round section tapering at the top with a sail track riveted on, was normally anodized a silvery color. The similar Australian Goldspar, has a distinct two sections frequently of different colors. The Elvstrom masts were usually anodized black, and some models are flatter at the top, to induce sideways bend at the top.