Garmin GPSMAP640: A Review From a Pocket Cruiser

Think You Might Need A Chart Plotter?

Clearwater Harbor FL Spoil Island

 Late in the last millennia at the very beginning of Sailing HideAway, a spanking new Garmin 120 GPS joined the equipment list of the SV hideaway.  Strangely, the main screen featured a highway complete with lanes that pointed towards the next waypoint.  If there was no waypoint, another screen provided track, position, altitude, and time. All the basic information needed for cruise navigation or day sailing was at hand. Without question a good chart and tools to plot it with were required.

Over the years the durable 120 became difficult to wake up in the morning, usually taking its time to find satellites and it could not plot a route to save its processor.  After Sixteen years of adventures a dark circle formed in the exact center of the display and grew in area ultimately becoming a total eclipse.

16 Years of Service 

The capt will admit to a certain reluctance to search for a replacement for the venerable 120.  The unwelcome discovery that an affordable GPS with a reasonably large screen unencumbered by other even more expensive toys has become an endangered species.  Many of the fully integrated units cost more than the boat is worth while providing too much information to be processed on a small sailboat.  Some units had screens so large they would distract the crew from actually sailing the boat.  An affordable GPS suffered from a screen too small to be helpful during the more exciting moments of the sailing experience.   No doubt there are plenty of handheld units that would work fine on a mountain trail but are useless on a heeling sailboat with a nearsighted navigator.

DOIN THE SEA FOG SLOG

Surely this year’s spring cruise to the distant Anclote Key could be made without electronic wonders.   Or so the capt believed until a sunny afternoon day sail became a sudden sea fog slog.  The HideAways had to admit navigating the shallows along Pass-A-Grill Channel at the tip of St Pete Beach in a dense fog without benefit of an electronic wonder may not end well.  The search began in earnest and since many of our escapades occur on the hard as well as water, the dual purpose Garmin GPS640 MAPS held particular interest.

It was difficult to justify the price until West Marine offered the unit at a couple of hundred dollars off the lowest price available at the time. 

Our new Garmin GPS640 Maps arrived in a large box of some heft.  This is significant because as we all know anything expensive must have these qualities in direct proportion to their cost to have real value.  The large hefty box included important documents, books, parts and accessories in impressive plastic bags that further justified the cost.  A word of caution is in order.  Offerings from some providers included remanufactured, refurbished or open frame units at a lower price. The fine print explained that while the unit would function properly some accessories may be missing.  Given all the parts, pieces and paraphernalia shipped in our box the risk was not worth taking and well worth the $40 difference.

First Impressions

The unit fits perfectly on a swing arm in HideAway’s companionway.  The nautical mount has a feature that scared the ptooohies out of us when first used.  One of us bumped the GPS pretty hard causing it to spin to almost vertical!   Turns out the mount has a clutch that allows for such impact. A nice amenity on a heeling sailboat.  

Garmin GPSMAP640

The mount has protected gold contacts and is of solid well thought out construction.  As reported by others, there is a significant glare issue with the screen.  We found tilting the unit slightly helps fend off the dreaded glare but some sort of shadow casting device would be helpful. The 640 comes with an impressive cover to guard from what I don’t know but it would be nice if it wouldn’t fall off if moved from horizontal.  We have to band it to the machine to transport.

View From the Helm

While I can see the screen from the helm the stats are difficult to discern.   Unless the sun is direct I could see our progress down the ICW and anticipate markers.  After all these years I can estimate speed, however those with better eyes may be able to recognize the speed data.   Note the designation print between mph and nm is too small to see on the screen at any distance.

The Touch Screen

The touch screen allows for a larger viewing area and is easy to use.  The panning function took some getting used to for the HideAways.   Be careful though, if you inadvertently touch the screen something on it will change.  In finding your way back to the right screen you may have to employ language some may feel inappropriate.  Interestingly it takes some effort to use the on/off switch.

As we sailed out of Pass-A-Grill channel entering crucial waypoints the 640 could not find marker G7A.  That might not mean much to you, but G7A is the closest marker with adequate water depth to afford the south bound intentions of the HideAways.  Full magnification was required to find the channel marker in a water way where 4 foot wakes are common.  How much fun can one sailor stand? After the waypoint is entered the mark will show at any magnification.

A Most Annoying Feature

Another feature of the GPS that is quite handy is the ability “measure distance” from one point to another.  For instance, if I want to measure the distance from G7A to the channel entrance it accurately calculated the distance at something over ten miles to my home.   That brings us to perhaps the most annoying feature of the duel purpose 640.  It has only one home base and that is located in the driving mode.   If you plot a future track in boating mode, all references are from your driving home.  Yes you can change your home to your yacht club or boat location but it is very inconvenient to do this on a regular basis and may not help anyway.  

The line next to the X should not be there

As it turns out the unit is designed to plot routes en route.  This may seem like a good idea while underway but who really wants to plan a route while on a hard reach aboard a small sail boat?  In one moment of exceptional high tech navigational blundering only a couple of screaming Ospreys (Fish Hawks if you live in the south) prevented the HideAways from impalement on the steel ICW channel marker that serves as their Dunedin Fl home.  

Do I Need a Route From My Dining Room Table to Anywhere? 

The route planning instructions recommend starting the route at the destination and work back to the starting point.    At one point I became so frustrated trying to build an accurate route from home that I drove to the end of the dock we usually depart and made a waypoint, incorrectly thinking that using that mark as a starting point would solve the problem.   Turns out the GPS will take into account where IT is located and nowhere else. Back at home or any other place in the world, the GPS will happily start the route from that location.  Oddly, I do not need a route from my dining room table to Anclote Key.   Planning routes has proven to be a frustrating waste of time.  Our solution is to a complete list of waypoints for any given cruise and navigate to them as needed.

Watch Sailing HideAway Videos

While we acquired the 640 for our cruise, most of our sailing takes place in well known waters within a few miles from our home port.  Our new high tech 640 requires that you have a destination in mind to display speed and other data and have plotted same on the Navigate To screen.  Worse, if you need a clock you must leave the screen. Try doing that on a rolling sailboat. The old 120 didn’t care where you were going, faithfully displaying speed and a clock full time.  Yes, you can go to the Compass screen for speed and other important data, but that screen does not show a chart or marks.   At least for us, that kinda defeats the purpose.   Should you desire the time you must go Home.  No, not to your house but it’s almost as bothersome, especially if you are trying to update your log while underway.  

Over all it appears the navigation function of the Garmin GPSMAP640 was designed and programmed by someone with little sailing experience sitting before a huge monitor bolted to something that cannot move.  I found the Help section of the Garmin website not useful and the map down load process extremely difficult.  I finally managed to download my one free updated street map but I don’t believe it made it to the machine residing instead on my hard drive.  Another problem for another day.

BlueChart g2 Vision SD Card 

There are other features available if you order the BlueChart g2 Vision SD card that uses high resolution satellite imagery in a 3D display and can connect your VHF, depth finder, water temperature, wind and other sensors.  If we lived aboard or had the time to cruise more often the BlueChart card would surely find its way aboard HideAway.

Is It Worth The Price?

Every time the unit is started a warning statement appears that you must agree with in order to proceed.  Basically it states the GPS is to be used only as a reference and that you accept full responsibility should you find yourself sailing off the edge of the earth.   At first I found it disquieting to learn that for all our technological advancement even professionals do not have confidence in their invention.   After returning from a 95 mile cruise I find myself in full agreement.  This or any other GPS is at best a reference and not capable of solo use.  A recent chart with the tools and knowledge to use them is essential.

That being written, the Garmin GPSMAP640 is a powerful and useful tool.  Recently the ability to access moon phase, tides and current  made the difference of a comfortable anchorage and a night of worry.    The reference section shows various services and contacts close to your current location, a very helpful feature when you’re low on fuel or need parts etc.   Waypoints are easy to make underway and it sure is handy to see where you are in relation to where you are going.  In an effort to maintain your sanity allow plenty of time to acquaint yourself with the 640 before you set off on a cruise.

By the by: The street function is much easier to live with and appears to learn common routes.

HideAway Near Honeymoon Island Fl 

SMALL BOATS ROCK!