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: 10 May 25 at 8:10pm
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
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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 D-Zero 316 |
Posted By: pondlife1736
Date Posted: 26 Jan 17 at 6:20pm
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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.
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Posted By: Time Lord
Date Posted: 26 Jan 17 at 10:33pm
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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  will do.
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