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Title: Tidal Stream Data?
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#1
Hi Folks,
I am new to Mac and to Mr Tides. I like the simplicity and clarity of the interface. However I do have a couple of questions about its use.
1, How do I get Mr Tides to display Tidal Stream Information? I cannot get Mr Tides to display Tidal Stream info' for the UK.

2, How can I get more "Map" information it would be useful to be able to zoom in on the local area rather than having the whole of the UK on screen?

3, Anchor Aid and calculations therein?
It seems to me that Anchor Aid could be a useful facility, however it does seem to lack some functionality. Is it possible to change some of the values used in the "Anchor Aid" facility?
In particular I would like to be able to change the Ratio of anchor rode (it is set to 3:1 for chain) I would also like to change the (or be informed of) the "clearance" under the keel at Low Water? I see this as being a variable dependent upon Size of vessel, nature of the sea bed, weather,
streams etc'.

It is possible that these features are already there it is just that I cannot find them.
Any and all help really Appreciated,

Simes
 
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#2
Simes Wrote:...it is set to 3:1 for chain...
Yikes! Show me someone who consistently uses to 3:1, even for chain, and I'll show you someone who's up in the middle of the night moving their anchor because they're dragging.

That number shouldn't be a default setting even if you can change it.
 
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#3
Simes Wrote:1, How do I get Mr Tides to display Tidal Stream Information? I cannot get Mr Tides to display Tidal Stream info' for the UK.

I use tidal stream harmonics to predict the the speeds of the streams and unfortunately it seems only the US and Canada produce these harmonics. Other locations have tidal stream values but I have never come across how these values are created. I think they come from mathematical models of the area and not from measurements at specific locations. In short, I have no information about tidal streams in the UK. Wish I did, though!

Simes Wrote:2, How can I get more "Map" information it would be useful to be able to zoom in on the local area rather than having the whole of the UK on screen?

The entire map interface is being replaced in Mr. Tides 3.1 with a vector shoreline that can be zoomed in much better. We lose color but gain flexibility. I'm in the middle of getting it running correctly, showing stations, etc.

Simes Wrote:3, Anchor Aid and calculations therein?
It seems to me that Anchor Aid could be a useful facility, however it does seem to lack some functionality. Is it possible to change some of the values used in the "Anchor Aid" facility?
In particular I would like to be able to change the Ratio of anchor rode (it is set to 3:1 for chain) I would also like to change the (or be informed of) the "clearance" under the keel at Low Water? I see this as being a variable dependent upon Size of vessel, nature of the sea bed, weather,
streams etc'.

The scope is fixed at 3:1 for all-chain and 10:1 for all-rode, based upon the recommendations of Chapman Piloting (who recommends 3:1 to 5:1), the Annapolis Book of Seamanship (4:1), and BoatUS (3:1). Unlike some who apparently don't know how to anchor properly, I've never dragged with 3:1 scope on my plow anchor - not even in 50 knots when other boats, with bigger anchors and more scope, dragged around me. I've set the hook in mud, sand, rock, and grass, and it has always held.

However, I can see how being able to set the desired scope would be a nice feature, so I'll add that to the list of things to do in v3.1

I can also add the depth under the keel at low tide. Maybe some kind of indication on the graphic? I'll see what works.

August
 
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#4
I guess it's the difference between someone who cruises for tens of thousands of miles at a time, anchoring for weeks at a time between marina visits and someone who sits behind a desk and dreams of sailing.

3:1 is, at best, the very minimum amount to use for an overnight anchorage. It's not good enough. In any real situation, almost everyone uses 5:1 or greater. I've been anchored for the last 5 days in 22 feet of water off Cumberland Island in Georgia. My 10 foot bow adds a significant amount to the scope. I have 200' of chain out giving a scope at high tide of better than 6:1. Through the week, about 6 other boats have dragged at one time or another but I haven't moved.

3:1 is a dangerous amount unless you're in an incredibly protected anchorage. It's probably what the other 6 boats were using.

I would strongly suggest changing the default to something higher, like 5:1, and without any question, allow the user to modify the fixed setting. There are times when I use 10:1 all chain scope. Every situation is different.

I always wondered why so many boats drag around in anchorages. I guess I'm getting a glimpse into why.
 
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#5
ActiveCaptain Wrote:I guess it's the difference between someone who cruises for tens of thousands of miles at a time, anchoring for weeks at a time between marina visits and someone who sits behind a desk and dreams of sailing.

With such a busy schedule, how do you find time to insult people you've never met?

ActiveCaptain Wrote:3:1 is, at best, the very minimum amount to use for an overnight anchorage. It's not good enough. In any real situation, almost everyone uses 5:1 or greater. I've been anchored for the last 5 days in 22 feet of water off Cumberland Island in Georgia. My 10 foot bow adds a significant amount to the scope. I have 200' of chain out giving a scope at high tide of better than 6:1. Through the week, about 6 other boats have dragged at one time or another but I haven't moved.

So you eat up a circle 260 feet in diameter (more at low tide) anchored that way. Enough room for two more boats. Tell me, is this in the middle of the anchorage? Most anchorage hogs are right smack in the middle, making life hard for other boaters.

ActiveCaptain Wrote:3:1 is a dangerous amount unless you're in an incredibly protected anchorage. It's probably what the other 6 boats were using.

Without knowing their anchors, the amount of rode, the bottom, etc., making ANY assumptions or conclusions is erroneous. If that many boats were dragging, I'd go help them and figure out what was going on. Then I'd know for sure and not have to guess. But I would still go with 3:1 as the acknowledged experts in this area agree with that number. It worked for me for 3 days in a gale while anchored in Port Neville, British Columbia.

ActiveCaptain Wrote:I always wondered why so many boats drag around in anchorages. I guess I'm getting a glimpse into why.

No, you're just assuming you know.
 
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#6
AugustH Wrote:With such a busy schedule, how do you find time to insult people you've never met?
1. It's Sunday and it's raining - I've got all the time in the world.

2. Heck August, I've known you for a while now. We don't need to meet.


AugustH Wrote:So you eat up a circle 260 feet in diameter (more at low tide) anchored that way. Enough room for two more boats. Tell me, is this in the middle of the anchorage? Most anchorage hogs are right smack in the middle, making life hard for other boaters.

Actually, 200 + 200 + 53 + 53 would be 506 feet in diameter. Usually good software developers are pretty good in math. Enough said.

And if the center of the anchorage is what's going to be safest for me, I'm in the center. You betcha.


AugustH Wrote:It worked for me for 3 days in a gale while anchored in Port Neville, British Columbia.
Yeah, that's proof. 3 whole days at 3:1. But maybe you got the math wrong and were at 6:1. You were half off above so you never know.
 
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#7
Guys,

Please stop the personal jibes.

Thanks,

Jon
Never knowingly overcanvassed!
 
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#8
Interesting micro soap opera when reasonable and talented people get in a pissing match..... nuff about that.

Related info:
http://speakingoffaith.publicradio.org/p...rgiveness/

Krista Tippett who does 'Speaking of Faith' podcast did this interview:
"Our guest, Michael McCullough, describes science that helps us comprehend how revenge came to have a purpose in human life. At the same time, he stresses, science is also revealing that human beings are more instinctively equipped for forgiveness than we've perhaps given ourselves credit for. Knowing this suggests ways to calm the revenge instinct in ourselves and others and embolden the forgiveness intuition." Personally, I think these are very fascinating insights into the neuro chemical foundations of revenge and confrontational discourse. When test subjects planned to punish their opponents, their brains showed activity in the part of the brain associated with pleasure and satisfaction. Confrontational discourse has an element of "Sweet Revenge". They discuss confrontation and revenge in primates and it's sad to see how close our behavior can be to the 'savage brutes'. Do the Ghandi thing and 'be the change you want to see in the world'.

Back on topic:
Fedex says our new iPad (3G, 64GB) is now clearing customs in China...... Hooray !!!!!
 
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#9
Hi AugustH,

Many thanks for the reply to my questions.
I do like Mr Tides and am testing it with local data here in Cowes UK. Remarkably accurate.

The scope function and the clearance function would be very welcome.

Once again many thanks

Simes
 
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