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Magnetic Compass Dinghy Install |
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Sam.Spoons
Really should get out more Joined: 07 Mar 12 Location: Manchester UK Online Status: Offline Posts: 3398 |
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Topic: Magnetic Compass Dinghy Install 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?
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Noah
Really should get out more Joined: 29 Dec 04 Location: United Kingdom Online Status: Offline Posts: 611 |
Post Options Quote Reply 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...
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Nick
D-Zero 316 |
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pondlife1736
Posting king Joined: 17 Jan 14 Online Status: Offline Posts: 106 |
Post Options Quote Reply 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.
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Time Lord
Far too distracted from work Joined: 03 Dec 13 Location: Warwickshire Online Status: Offline Posts: 301 |
Post Options Quote Reply 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.
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Merlin Rocket 3609
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Sam.Spoons
Really should get out more Joined: 07 Mar 12 Location: Manchester UK Online Status: Offline Posts: 3398 |
Post Options Quote Reply Posted: 26 Jan 17 at 11:46pm |
Brilliant, WTF didn't I think of that will do.
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