Print Page | Close Window

Magnetic Compass Dinghy Install

Printed From: Yachts and Yachting Online
Category: General
Forum Name: Repair & maintenance
Forum Discription: Questions & tips on the subject
URL: http://www.yachtsandyachting.com/forum/forum_posts.asp?TID=12640
Printed Date: 11 Dec 17 at 2:20am
Software Version: Web Wiz Forums 9.665y - http://www.webwizforums.com


Topic: Magnetic Compass Dinghy Install
Posted By: Sam.Spoons
Subject: Magnetic Compass Dinghy Install
Date Posted: 25 Jan 17 at 2:24pm
I'm planning to install a Silva 103 on my Spice using a Selden Mast Mount. I know that ferrous metal fittings can cause deviation, and I know that stainless steel, while barely magnetic is still a ferrous metal alloy. However, how much effect (if any) are things like ss kicker fittings (no wire rope just dyneema) going to have, and should I use brass bolts to fix the compass to the bracket or are ss ok?



Replies:
Posted By: Noah
Date Posted: 26 Jan 17 at 10:15am
I've never considered potential variation in my dinghy compass, which happens to be a tacktick. Given that we're never out of sight of land (excepting fog!) and its use is tactical, not navigational, I think any errors are irrelevant. Happy to hear conflicting views though...

-------------
Nick
http://www.fireballsailing.org.uk/register/boat_info.php?sail_no=14821" rel="nofollow - GBR 14821: Sijambo


Posted By: pondlife1736
Date Posted: 26 Jan 17 at 6:20pm
Marine grade austenitic 316 stainless steel should be OK as it is barely magnetic. The problem is when it is cold worked or welded which can change the micro-structure into ferritic, ie much higher magnetic susceptability.
Easy to check with a magnet though.


Posted By: Time Lord
Date Posted: 26 Jan 17 at 10:33pm
Or even simply putting the bit in question near to the compass and see what happens to the needle as you move the bit around.

-------------
Merlin Rocket 3609


Posted By: Sam.Spoons
Date Posted: 26 Jan 17 at 11:46pm
Brilliant, WTF didn't I think of that Beer will do.



Print Page | Close Window

Bulletin Board Software by Web Wiz Forums® version 9.665y - http://www.webwizforums.com
Copyright ©2001-2010 Web Wiz - http://www.webwizguide.com