SailNet Community - Reply to Topic

   Search Sailnet:

 forums  store  


Quick Menu
Forums           
Articles          
Galleries        
Boat Reviews  
Classifieds     
Search SailNet 
Boat Search (new)

Shop the
SailNet Store
Anchor Locker
Boatbuilding & Repair
Charts
Clothing
Electrical
Electronics
Engine
Hatches and Portlights
Interior And Galley
Maintenance
Marine Electronics
Navigation
Other Items
Plumbing and Pumps
Rigging
Safety
Sailing Hardware
Trailer & Watersports
Clearance Items

Advertise Here






Go Back   SailNet Community > Out There > Cruising & Liveaboard Forum > Full or fin keel?
 Not a Member? 


Thread: Full or fin keel? Reply to Thread
Title:
  

By choosing to post the reply below you agree to the rules you agreed to when joining Sailnet.
Click Here to view those rules.

Message:
Trackback:
Send Trackbacks to (Separate multiple URLs with spaces) :
Post Icons
You may choose an icon for your message from the following list:
 

Register Now

In order to be able to post messages on the SailNet Community forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.
Please note: After entering 3 characters a list of Usernames already in use will appear and the list will disappear once a valid Username is entered.
User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.



Click here to view the posting rules you are bound to when clicking the
'Submit Reply' button below


Additional Options
Miscellaneous Options

Click here to view the posting rules you are bound to when clicking the
'Submit Reply' button below


Topic Review (Newest First)
07-29-2013 05:53 PM
mstern
Re: Full or fin keel?

Quote:
Originally Posted by Jeff_H View Post
One of the things which is happening on the more extreme versions of the small root keels is that they are building 'cassette' style keel connections in which the end of the keel inserts into a tightly fitting box inside the hull. This allows a much bigger contact area to resist bending and torsion. Of course the box needs to be heavily constructed and needs a sophisticated transverse and longitudinal framing system to be able to distribute loads outward into the hull.

FWIW I like Garden's work aesthetically and from a historic point of view.

Jeff
That sounds like what Seaward does with its retractable keels; the high aspect keel slides up and down a box that looks (at least on their website's videos) to be rather robustly incorporated into the hull. Makes sense as a way to spread the load of a grounding even if the foil is nonmoving.
07-29-2013 03:46 PM
Jeff_H
Re: Full or fin keel?

One of the things which is happening on the more extreme versions of the small root keels is that they are building 'cassette' style keel connections in which the end of the keel inserts into a tightly fitting box inside the hull. This allows a much bigger contact area to resist bending and torsion. Of course the box needs to be heavily constructed and needs a sophisticated transverse and longitudinal framing system to be able to distribute loads outward into the hull.

FWIW I like Garden's work aesthetically and from a historic point of view.

Jeff
07-29-2013 03:25 PM
bobperry
Re: Full or fin keel?

Kef:
I still have the Garden design catalog he gave me whan I was 15 years old and depsite being referred to and read countless times I am happy to say it is not falling apart. I know where it is right now. I always know where it is. Wish I had had the brains to have had him sign it.

The SLIVER Project boat was moved last week to the yard in Seattle where it will be finished. Here are some pics
07-29-2013 03:05 PM
keforion
Re: Full or fin keel?

Bob:

Thanks for the reply and photo of Sliver's floors. Looked up "the Sliver Project" on the web ... OUTSTANDING.

Nice to read of your love of Wm. Garden. I checked his books out of the libary as a kid and pored over them for so long that they eventually fell apart -- maybe it was just books with his designs in them. And your love of 30 Square's as well. There was one moored in Mariner Lagoon for years that I drooled at. It was eventually hauled to Svendsen's in Alameda and rebuilt by Peter Schwab. He raced in the Singlehanded Transpac to Japan, but I can not recall the result. (Probably won.)

Sorry for the thread drift -- but, just had to thank you.

"Bob, You done good."

kef
07-09-2013 07:45 PM
bobperry
Re: Full or fin keel?

Kefer:
Not a bad idea. In a heeled position one leg of the fin woud be near vertical and that's good. The problem with any configuration of "tandem" keel isthat you have two trailing edges and more drag. There are a number of way to join high aspect ratio fins to hulls. On the SLIVER project we spread the loads out with a series of steel floors that all fasten to the outboard longitudinals that form the front of the setee faces. Keel bolts are well outboard in a T flange and extend all the way up through the floors. I'll see if I can find a photo.

The problem we had with the SLIVER was that the strip planked cedar hull was not capable of taking the keel bolt compressive loads without crushing. So we have to take the loads off the skin entirely. The wood strip planking was removed in a big pan shape around the keel and replaced with solid laminate.

Ok, found one:
07-09-2013 07:23 PM
keforion
Re: Full or fin keel?

Still going,eh?

Seems to me that one of the design problems with modern beamy hulls equipped with high aspect ratio and deep fins, and the resulting high bending stresses at the foil to hullbottom join, could be alleviated by using two foils, in a "V" configuration, with the bottom ends joined at the ballast bulb below and the top end affixed to the hull near the chines or bilges. The foils then are in almost pure tension and compression, aside from the lift force, with almost no bending stress.

Has anyone tried this?

K E Froeschner
Martin, Froeschner & Associates
Morgan 45 "Orion"
05-22-2013 06:02 PM
copacabana
Re: Full or fin keel?

OK. Thanks for the clarification.
05-22-2013 05:45 PM
Jeff_H
Re: Full or fin keel?

It is not being moved to "Off-Topic". Two posts were moved to a thread that only the moderators can see. We were asked to disclose when we moved things out of sight. That is why the bread crumbs were left.
05-22-2013 05:28 PM
copacabana
Re: Full or fin keel?

Jeff, I don't see the thread in the off topic forum. I think it's a shame to move it there over a few differences of opinion, especially when it's one of the more informative threads going right now on SN. Unless I missed something, it's been pretty civil so far.
05-22-2013 04:50 PM
Jeff_H
Re: Full or fin keel?

The moderators have moved two off topic post to Holding for further review.
This thread has more than 10 replies. Click here to review the whole thread.

 
Posting Rules
You may post new threads
You may post replies
You may post attachments
You may edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On


All times are GMT -4. The time now is 07:04 PM.

Add to My Yahoo!         
Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
SEO by vBSEO 3.6.1
(c) Marine.com LLC 2000-2012

The SailNet.com store is owned and operated by a company independent of the SailNet.com forum. You are now leaving the SailNet forum. Click OK to continue or Cancel to return to the SailNet forum.