Cruisers Forum
 


Join CruisersForum Today

Reply
  This discussion is proudly sponsored by:
Please support our sponsors and let them know you heard about their products on Cruisers Forums. Advertise Here
 
Thread Tools Search this Thread Rate Thread Display Modes
Old 27-02-2020, 06:04   #1
Registered User

Join Date: Oct 2017
Posts: 6
A frame on a five metre wide Kat?

1 Height of A frame to width of Kat
2 Is there a mathematical formula
3 What tension is required for the steel rope
I am sorry if this is not the right term for the A frame, but it is the
Only way to describe it.
I would be grateful for any information.
Fred
__________________

fred278 is offline   Reply With Quote
Old 27-02-2020, 06:48   #2
Registered User
 
Sailmonkey's Avatar

Join Date: Sep 2009
Location: Houston
Boat: '76 Allied Seawind II, 32'
Posts: 7,620
Re: A frame on a five metre wide Kat?

Iím not even sure what it is youíre asking about?

This is posted in anchoring and mooring so Iím even less sure of what youíre looking for.
__________________

Sailmonkey is offline   Reply With Quote
Old 27-02-2020, 08:56   #3
Registered User
 
Sailmonkey's Avatar

Join Date: Sep 2009
Location: Houston
Boat: '76 Allied Seawind II, 32'
Posts: 7,620
Re: A frame on a five metre wide Kat?

Iíve just had a thought....are you asking about the pelican striker on the forward crossbeam? The strut that supports the loads from the forestay?
Sailmonkey is offline   Reply With Quote
Old 27-02-2020, 19:34   #4
Registered User

Join Date: Nov 2009
Location: lakeville ma.
Boat: corbin39
Posts: 124
Re: A frame on a five metre wide Kat?

Maybe he is asking about the load on a cross beam on a cataram ?
B-Baysailer is offline   Reply With Quote
Old 28-02-2020, 08:00   #5
Registered User

Join Date: Oct 2017
Posts: 6
Re: A frame on a five metre wide Kat?

Thank you for trying to help.I'll try to explain it better. 1. If you stand in front of the cat in the middle of the cross member at the front there is a triangle of steel piping, what is the name of this? 2. From the apex of the triangle is a steel wire running to each hull. Is there a mathematical formula regarding height and tension of triangle and wire.
Again thank you for your help and patience. Fred
fred278 is offline   Reply With Quote
Old 28-02-2020, 08:10   #6
Registered User

Join Date: Nov 2009
Location: lakeville ma.
Boat: corbin39
Posts: 124
Re: A frame on a five metre wide Kat?

I think it's called resolving force do a Google search for that
B-Baysailer is offline   Reply With Quote
Old 28-02-2020, 11:14   #7
Registered User

Join Date: Jul 2012
Location: North East USA
Boat: 1975 Tartan 41'
Posts: 405
Re: A frame on a five metre wide Kat?

Just simple balance of forces with the forestay pulling up on the cross beam, the tension in the wire pushes down on the vertical tubing attached to the cross beam. I haven't done a free body diagram, but I think the balance is:
2 * (Cos angle)*(wire tension) = Vertical forestay tension



2 because the wire is on both port and stbd so it acts twice on the vertical tube.

the "angle" is between the cross wire and vertical.



use similar trig to solve for vertical tension in forestay load, which for this you could assume 15-20% breaking strength I'd guess... but i'm not a rigger.
zstine is offline   Reply With Quote
Old 28-02-2020, 14:36   #8
Registered User
 
Jamme's Avatar

Join Date: Feb 2020
Location: New York
Boat: Beneteau Oceanis 31
Posts: 34
Re: A frame on a five metre wide Kat?

FWIW... I think the "A frame" is called "seagull striker". The "V frame" (if any) is called "dolphin striker."

I was looking at this video: an original (don't know if / how safe) way of rigging the striker:
__________________
"I always arrive late at the office, but I make up for it by leaving early.Ē Ė Charles Lamb
Jamme is offline   Reply With Quote
Old 13-03-2020, 08:02   #9
Registered User

Join Date: Oct 2017
Posts: 6
Re: A frame on a five metre wide Kat?

Quote:
Originally Posted by B-Baysailer View Post
I think it's called resolving force do a Google search for that


Thank you very much for the information
Fred
fred278 is offline   Reply With Quote
Old 13-03-2020, 08:04   #10
Registered User

Join Date: Oct 2017
Posts: 6
Re: A frame on a five metre wide Kat?

Quote:
Originally Posted by zstine View Post
Just simple balance of forces with the forestay pulling up on the cross beam, the tension in the wire pushes down on the vertical tubing attached to the cross beam. I haven't done a free body diagram, but I think the balance is:
2 * (Cos angle)*(wire tension) = Vertical forestay tension



2 because the wire is on both port and stbd so it acts twice on the vertical tube.

the "angle" is between the cross wire and vertical.



use similar trig to solve for vertical tension in forestay load, which for this you could assume 15-20% breaking strength I'd guess... but i'm not a rigger.


Thanks that's great
Fred
fred278 is offline   Reply With Quote
Old 13-03-2020, 08:05   #11
Registered User

Join Date: Oct 2017
Posts: 6
Re: A frame on a five metre wide Kat?

Quote:
Originally Posted by zstine View Post
Just simple balance of forces with the forestay pulling up on the cross beam, the tension in the wire pushes down on the vertical tubing attached to the cross beam. I haven't done a free body diagram, but I think the balance is:
2 * (Cos angle)*(wire tension) = Vertical forestay tension



2 because the wire is on both port and stbd so it acts twice on the vertical tube.

the "angle" is between the cross wire and vertical.



use similar trig to solve for vertical tension in forestay load, which for this you could assume 15-20% breaking strength I'd guess... but i'm not a rigger.


That is very informative. Thank you.
Fred
__________________

fred278 is offline   Reply With Quote
Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Backstay to Bimini frame frame concern. MollyJo Deck hardware: Rigging, Sails & Hoisting 19 20-10-2016 11:38
[SOLD] Bimini Frame 91" wide sanibel sailor Classifieds Archive 2 25-06-2015 03:04
For Sale: Stainless Bimini frame 91" wide sanibel sailor Classifieds Archive 1 11-01-2015 06:59

Advertise Here


All times are GMT -7. The time now is 03:33.


Google+
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2020, vBulletin Solutions, Inc.
Social Knowledge Networks
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2020, vBulletin Solutions, Inc.

ShowCase vBulletin Plugins by Drive Thru Online, Inc.