Author Topic: External Round Chainplates Design  (Read 2685 times)

Soggy Geek

  • Administrator
  • Hero Member
  • *****
  • Posts: 527
    • View Profile
    • Cruise Around the World with Soggy Paws
  • Boat Type: CSY 44 WT
  • Boat Name: Soggy Paws
Re: External Round Chainplates Design
« Reply #15 on: May 15, 2019, 05:19:31 PM »
Pictures of the Soggy Paws job here:

http://svsoggypaws.com/csy/rig.htm#Chainplates
Soggy Paws the CSY has been sold but not forgotten!
http://svsoggypaws.com/CSY/

Soggy Geek

  • Administrator
  • Hero Member
  • *****
  • Posts: 527
    • View Profile
    • Cruise Around the World with Soggy Paws
  • Boat Type: CSY 44 WT
  • Boat Name: Soggy Paws
Re: External Round Chainplates Design
« Reply #16 on: May 15, 2019, 05:25:14 PM »
And Beaujolais helpful detailed writeup is here:

http://svsoggypaws.com/csy/beaujolaischainplates.htm
Soggy Paws the CSY has been sold but not forgotten!
http://svsoggypaws.com/CSY/

Ron Sheridan

  • Jr. Member
  • **
  • Posts: 10
    • View Profile
    • Memory Rose is For Sale
  • Boat Type: CSY 44 PH
  • Boat Name: Memory Rose
Re: External Round Chainplates Design, Original drawing
« Reply #17 on: August 26, 2019, 01:25:04 PM »
Hello gang,
Have been off this site for years but checking back in saw some discussion on the Round Chain Plate design I had come up with in the latter 90's.  My design, was a take off of a design by Tillerson Pearson and Steve Dashew for the manufacture 54'-62' Deerfoot Yachts. You can see their design (10 bolts) in the Dashew's Cruising Encyclopedia page 582. For manufacturing it made a lot of sense, as you could make All chain plates the same and just rotate the tang in the direction needed.  Installation was easy, just drill and insert the center bolt first, the rotate the tang in the direction of the rigging wire, or attach it.  Drill the remaining holes, insert bolts and so on. Easy.  CSY used 3/8" tang material (304 SS) welded to a 1/4" triangular backing plate, with 6 bolts.  I used 1/2" (316 grade SS) (no welds needed and 8  "Counter Sunk" headed bolts also 316 grade.  Plated cut on a C&C machine, but later ones were made at a machine shop locally for other owners and looked perfect as well. Note, countersinking the heads, offered crevice corrosion protection.  Many Hex Head bolts used on CSY's failed, heads snapping off because water/moisture could gain access under the head and over time, crevice corrosion cause the stainless to fail.
Here's a few photos from 2000/2001.
 Note, back in the day, I payed about $300/Plate for material, cutting, final polishing(I did it up to 600 grit).  the bolts alone back then were $9.69 each plus Aircraft 316 Nylock nuts and 1/2" large flat washers for the interior.  I ordered 100 as my Pilothouse was a ketch requiring more plates/bolts.
Important I feel is that, without the ability for heavier material used and double width tangs (4" double vs 2" single) and 1/2 thick material vs 3/8's as well as 8 bolts rather than 6, the plates should last 1/2 century! I feel reason this method makes Chain Plates totally trustworthy for many decades....many.
The limit here on 'file size' prohibits me from including a the diagram which is 178 ks' vs 158 allowed, so I'll post a few of these on my blog site for those interested.https://memoryrose.blogspot.com/search/label/Chain%20Plates
Hope this helps anyone engaged in this project.

Ron Sheridan

  • Jr. Member
  • **
  • Posts: 10
    • View Profile
    • Memory Rose is For Sale
  • Boat Type: CSY 44 PH
  • Boat Name: Memory Rose
Re: External Round Chainplates Design
« Reply #18 on: August 26, 2019, 01:29:47 PM »
...click any photo for a slightly larger version if needed.