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+--- Thread: Release 11 available (/thread-361.html)
Release 11 available - AugustH - September 4, 2007
Mr. Tides 3 release 11 is available for download. Either use the "Check for Update" feature of Mr. Tides 3, or go to http://idisk.mac.com/augusth/Public/MrTides3.zip to get it.
New features include Anchor Aid, that will tell you if it's safe to anchor near a particular tide station, enhanced calendar view that shows only text, bug fixes with the Growl notification engine, improved document handling (no longer must you save every time you change tabs - it's done for you automatically!), and other fixes. The complete change list is at http://web.mac.com/augusth/Tides3/Latest_Release.html
Enjoy!
August
- jagasail - September 4, 2007
August,
Very good! I was playing with the anchor tool earlier today and it's quite useful. One comment, though, the scope guide is assuming you're attaching your anchor line to the bow right at the water line, and not including the hight of th bow roller above water. This really should be included in a scope calculation. For me, with my bow 4' above water, it's easy to add 12' to the calculated scope, but having the option to input that along with keel depth would avoid the chance of forgetting. Just a suggestion.
One other question - (may be a GPSNavX question), when I right click on MacENC to open Mr. Tides, it seems to open the nearest station, whether tides or current, and doesn't allow me to specify. Too frequently in the San Juans it opens to a current station when I want a tide station. Is there a way to do this?
All in all, a Mr. Tides is a great tool.
Scot
- GPSNavX - September 4, 2007
To use Mr. Tides in GPSNavX or MacENC. [control] click on the chart where you want tides or currents. Select "Mr. Tides" on the context menu. Mr. Tides will open to the nearest station where you clicked. To see other stations select "Find Stations > By Distance" on the Mr. Tides "Maps" menu. This will list all stations sorted by distance near where you clicked. Select a Current or Tide station to your benefit.
Ok here is a slight problem with including the bow height in a scope calculation. As you let all that chain out of the bow locker, your bow rises
I was always taught that heavy things should not go in the ends of airplanes or boats - so why do so many cruisers put heavy chain and anchors on the bow and a big dinghy, arches, anchors, etc. on the back of the boat?
- jagasail - September 5, 2007
GPSNavX Wrote:Ok here is a slight problem with including the bow height in a scope calculation. As you let all that chain out of the bow locker, your bow rises
OK, the simple answer is too many 'cruisers' haven't a clue what they're doing when it comes to anchors... Roche Harbor in summer (as you may be aware) is a perfect example. I won't anchor there - too many loonies who drop 35 feet of rode in 30 feet of water, then get pissed at you when you even lay out a 2.5 : 1. Now on your other point, I'm sure August could put in some calculations that would compensate for the rise in the bow. He'd just need total displacement, hull shape, weight of chain, whether you store the beer in the front, mid, or stern...
August, I though I saw a response from you earlier this morning - did you delete it?
Actually, my concern is that Mr. Tides currently undercalculates the required rode. Rather than explain, I'll just quote a piece from Steve Dashew's "Practical Seamanship":
Quote:Scope is an often misunderstood concept. What we are looking
for is the total height of the anchoring system, from bow roller to
sea bottom. This height (water depth plus height of the bow) is
divided into the length of the rode to develop the scope.
Take this drawing as an example. Say water depth (WD) is 10-
feet (3-meters), and the bow is 5-feet (1.7-meters) high. That
gives us a total height of 15-feet (4.6-meters). To find the
required scope simply multiply 15 feet by the desired scope—in
this case let’s say seven-to-one. 15 feet times seven-to-one
scope equals 105 feet (32 meters).
Unfortunately I couldn't include the drawing, but you get the idea. Scope is trying to control the angle of the rode from the anchor to the boat, and since you generally attach the rode to the boat at the bow rail rather than at the waterline, this increases that angle. Thus you need to include bow height in the calculation. The shallower the water the more important it is.
August, you probably know all this, but I put this in since there's so many people who don't understand scope.
Scot
Anchor Aid - AugustH - September 26, 2007
Oh yes I'm aware that the height of the bow roller needs to be accounted for in the calculation of scope. I know my bow is about 4 feet above the water so I add in the extra 12 feet, since I'm all-chain. My boat is a Good Old Boat (Ranger 37) and it doesn't rise up as I let the chain out. I think that has something to do with the sheer amount of glass in the hull
I'll look into adding another box to Anchor Aid for the height of the bow roller. Anything to help people anchor better. I too have seen some frightening attempts at anchoring. Liberty Bay off Poulsbo on the 3rd of July, when everyone's been drinking and the anchorage is completely full of raft-ups, some with 3 or more boats hanging on one hook, is truly a sight to make one shudder!
August
GPSNavX and Mr. Tides - AugustH - September 26, 2007
Currently Mr. Tides will open the first station found near where GPSNavX is asking for. This may be a tide station or it may be a current station. I'll look into how to make Mr. Tides better at selecting which to open. This may be a preference item or a dialog, but I'm not sure right now.
I can see trouble already if the preferred station type is located farther away from the point than the non-preferred type, or if there isn't a preferred type in the range I search on.
Hmm lots of questions, not many answers right at this moment - but I'll work on it!
Tanks!
August