Max weight of shat/prop on cutlass bearing - SailNet Community

   Search Sailnet:

 forums  store  
LinkBack Thread Tools
Old 05-30-2008   #1
Join Date: Oct 2006
Location: St Thomas, USVI
Posts: 49
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 0
kaakre is on a distinguished road
Max weight of shat/prop on cutlass bearing

Am refitting and old steel ketch. Deleted the old grease filled prop shaft system in favor of a cutlass bearing and a prop shaft seal in the seven foot tube. Will pump water into the tube for lubrication of the PSS and Cutlass bearing.

It has about a 12 foot by 2 1/2 inch prop shaft. Weight of the shaft is about 140 pounds and the prop is about 60 pounds. The support of the overall shaft and prop weight comes from the transmission flange connection, a bearing 2 feet aft of that connection and the cutlass bearing at the stern. In short. the majority of the weight of the shaft and prop are likely carried by the cutlass bearing.

The question is-- how much shaft/prop weight can a cutlass bearing support without excessive wear or deforming? The cutlass bearing is about 3 1/8 by 2 1/2 by 10 inches. This info may be on a website somewhere but I have not found it.


kaakre is offline   Reply With Quote Quick reply to this message Share with Facebook
Old 05-30-2008   #2
Senior Member
Join Date: Apr 2008
Posts: 476
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 8
negrini is on a distinguished road
Send a message via AIM to negrini Send a message via Yahoo to negrini Send a message via Skype™ to negrini
That should not be simple. The weight you mention has influence on statical support only, what means almost nothing to the propeler system. Major stress are posed by dinamic forces. So, imagine the forces acting on your cutlass when spinning, while boat pitching, a stern waves, missalignement of the flange, non homogenous shaft and prop creating centrifugal forces, bad balancing, etc ... These are in fact the real stress and wear over your cutlass bearing. Now, how much yours can stand, will depend on material type, age, thickness, etc... Not a simple answer, and probably manufacturer could give you the rule of thumb plus safety factor ....
negrini is offline   Reply With Quote Quick reply to this message Share with Facebook

Quick Reply

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

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:
Please enter a password for your user account. Note that passwords are case-sensitive.
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:


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.

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
Thread Tools

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

Similar Threads
Thread Thread Starter Forum Replies Last Post
PS 37 Cutlass Bearing waypt1 Pacific Seacraft 5 01-15-2008 03:03 PM
Cutlass Bearing Replacement, 1985 Najad 343 kc_cmc Gear & Maintenance 2 12-07-2004 02:15 PM
Installing a Cutlass Bearing Mark Matthews Gear and Maintenance Articles 0 04-26-2002 08:00 PM
Loose Cutlass Bearing Sue & Larry Gear and Maintenance Articles 0 02-18-2002 07:00 PM
Cutlass Bearing Query SailNet Gear and Maintenance Articles 0 06-06-2001 08:00 PM

All times are GMT -4. The time now is 12:30 PM.

Add to My Yahoo!         
Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2015, vBulletin Solutions, Inc.
User Alert System provided by Advanced User Tagging v3.1.0 (Pro) - vBulletin Mods & Addons Copyright © 2015 DragonByte Technologies Ltd.
(c) LLC 2000-2012

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