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Viper 640 North American Championship

The Viper 640 North American Championship was held last week (July 24-27), as part of the Marblehead NOOD regatta.  As a new owner of a Viper 640, I was thrilled to be offered the opportunity to charter a boat for the regatta, and jumped at the chance to attend the event.  After all, what better way to get up the learning curve quickly on the Viper 640 than to attend the North American Championship? 

We had 26 boats registered, and a very deep, competitive fleet.  The number of competitors has increased by 45% for two consecutive years mirroring the growth of interest in this modern 21 foot sportsboat. The Class Association has grown from a mere 20 boats 2 1/2 years ago to 100 boats in North America today. What makes this growth particularly remarkable is that it occurred without the extensive marketing and promotion usually associated with the launch of one-design sportsboat classes. The Viper class pursued a different formula.

Quoting Justin Scott, current president of the Viper Class, “It was back to the future.  The great classes of yore like the Lightning and the Etchells and the Star were not launched with a large marketing campaign and expensive advertising budgets, They were beautifully designed, well built boats and the classes grew by word of mouth because they were fun boats to race and sailors told other sailors about them.  It seemed to us that the age of the internet made ‘word of mouth’ possible again, and that we had come across a beautifully designed, well built, modern equivalent of those great classes”.  Justin and the other founders of the Viper 640 Class Association believed there was a place for such a boat and furthermore that if existing owners spread the word and if sailors could buy the Viper directly from the builder, costs could be kept down and the Viper could provide a much needed value for money modern one-design boat for the North American sailing community.  So far, the ‘word of mouth’ formula has been a huge success, with new Viper 640 fleets starting around the country and the builder of the boat, Rondar Raceboats, shipping new boats as fast as they can build them.

Our adventure began Wednesday, July 23rd.  Our crew was converging from far and wide:  Charles, my old high school friend, who would be trimming the kite (and hereafter shall be known as “The Kite Man Trimmeth”), was flying up from his home in Annapolis (lucky dog).  Knox R., who would be splitting the charter with me and co-skippering the boat, was flying in from Atlanta, and I was coming from Austin, TX.  The plan was for all of us to fly in to Boston on Wednesday evening, and meet at the boat bright and early Thursday morning to launch the boat, and get some practice time (the three of us had never sailed together) before the beginning of the regatta.  Riiiiiight….  

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New Toy - Velocitek SC-1

Well, I couldn’t resist any more… I finally succumbed to the temptation and bought a Velocitek SC-1 GPS-based Speedometer/Compass/VMG/Timer.   Made by a little outfit in Hawaii, the SC-1 can display real-time speed, heading, or VMG, all based on a GPS signal.  It also includes a start timer, and can even display proximity to the start line when you’re in the pre-start for a race.

 The VMG function, which displays your VMG relative to a wind direction that you enter into the unit, will be very useful in figuring out the best angles to sail downwind on the Viper 640.  Being fairly new to the viper, this is an area I really need to work on.

I’ve been playing with GPS on my sailboat for quite a while, and even created a little utility to help set up a “regular” GPS to display VMG relative to a heading, to mimic the functionality of a Velocitek SC-1 (see download page).  However, there’s no substitute for the real thing… The SC-1 has HUGE, easy to read numbers on the display, a much faster display update rate than a “regular” GPS like the old Garmin handheld unit I was using before, and a much simpler user interface.  Perhaps most important, it calculates and saves your speed data using the most accurate method: doppler shift measurements off the GPS sattelite signals.  All other “regular” GPS units, like my old Garmin, don’t store doppler information in their track data, so when you analize your speed on your PC, the speed has to be calculated via “time/speed/distance” calculations between individual GPS “breadcrumbs” in your track file.  Given the positional error possible for each track point, this calculated speed can obviously fluctuate quite a bit.

 I’m working out the best mounting solution for the SC-1 on the Viper 640.  More photos and GPS replays to come once I have the unit in the boat and have had a chance to play with it some more.

Making a hole in the boat - or how to install new hardware in a challenging location

As I upgrade my Viper 640 to mirror the placement of the controls on the new Rondar-built boats, I needed to relocate a turning block for the spinnaker halyard/retrieval line to a new location on the cockpit floor.  Unfortunately, the underside of this new location was impossible to reach through any existing inspection port, so there was no way to easily install a backing plate into which I could then screw the eye strap for the new block.

To use business-speak, this challenge presented an opportunity to apply a hardware installation method suggested by Brian Bennett, the designer of the Viper 640.  Thanks, Brian for the process.  It worked like a charm!  Using your method it’ll be possible to install hardware pretty much anywhere on the boat without having to cut any new inspection ports to get at the underside of hardware locations.

Here are Brian’s instructions verbatim:

“As the boat is Epoxy, the best local repair and strenghtening can and should be done with G-10 (Garolite). This is a compressed fiberglass sheet product which can be tapped into (and American made). Because the Viper is a big can, you need to use a material than can be tapped without need for backfastenings. G-10 will do this. You will have to cut a hole (or slot), sand the piece of G-10 (I would recommend 8 - 10mm), and epoxy the contact side, before passing thru to the inside, and holding up in place while it cures. In the past I have used a piece of seizing wire, then just cut the wire when the epoxy goes off.
The core can then be backfilled with epoxy and the outside sanded and finished. Then your hardware can be installed via drill and tap method. The G-10 should be twice the size of the fitting you are installing.” 

Here are a few photos of the process on my boat:

Brian had recommended 8 to 10mm thick G-10.  I had access to some sheets of 1mm thick material (Thanks, Dave!), so I ended up building up a sandwich of 8 layers of the stuff epoxied together under mild pressure, which yielded almost 10mm thickness.  And man, this stuff is dense and strong!  Given that my 10mm thickness of G-10 was home made, I wanted to test it to make sure I could drill & tap it, and then also test its screw-holding capacity.  So I drilled and tapped a hole for a 10-24 screw in the corner of the backing plate, which went smoothly.  Here you can also see that the backing plate has been scored agressively (with coarse sandpaper and a hack saw blade) to help it bond to the deck once it gets epoxied.

Next, it was time to put a screw into the freshly made threaded hole, and test the G-10’s screw-holding power.  In this photo you can see the screw in the backing plate, but unfortunately I didn’t get a picture of the next step;  I clamped the G-10 with the screw in it to a workbench, put a pair of vise grip pliers on the screw head, and tried to yank the screw out of the G-10 as hard as I could.  I ended up picking up the corner of the workbench, and the screw didn’t budge (nor did the G-10 flex at all, for that matter.  This stuff is STRONG!)  So, the test was declared a success.  Time to get to work on the boat! 

This step one was the easiest, AND most terrifying… cutting a slot into the cockpit floor.  Below you can see the slot cut in the cockpit floor, with the backing plate that will go in the hole, and the eye-strap that is the point of this whole exercise. 

Below you see a test fit of how the backing plate will be inserted in the hole in the next step.

Next, I drilled a couple of small holes in the backing plate, exactly where the screw holes for the pad-eye will eventually be, and led a couple of long pieces of thin wire through those holes.  The wire is there to pull the backing plate back up against the underside of the cockpit floor once it’s been fed through the slot in the floor.  I put the wire exactly where I want the screw holes for the hardware to eventually be, for two reasons that should become obvious shortly.

Now it was time to mix up some epoxy.  Two pumps of West system were enough for the job, with some high-density filler mixed in to thicken it slightly so it wouldn’t all drip off the backing plate while I was sliding it into the hull.  I covered the bonding surface of the backing plate with epoxy, and fed it into the slot being careful to hold on to the wire “tails”!

Once the plate was inside the slot, it was easy to flip it flat against the underside of the deck and maneuver it into place with the two wire tails.  By centering the two pieces of wire in the slot, I could also make sure the backing plate was located exactly where I wanted it (one of the reasons to drill for the wires where the screws will eventually go.  In this picture, you can see the very high tech (NOT!) scrap-lumber tripod and screwdriver used to tighten the wire, pulling the backing plate up against the underside of the deck.
The Shiner Boch is there purely to provide scale and some Texas authenticity to the project. 

Once the backing plate was held in place by the tripod, I filled in the rest of the slot with thickened epoxy.  Here I should have thickened the epoxy further, to “peanut butter” consistency, so I could fill the slot and then scrape off the excess with a straight edge.  The way I did it, I ended up overfilling the slot and couldn’t scrape it flat since the epoxy was too liquid.  This made for a little more grinding work later to flatten the epoxy.

After the epoxy set, the wire tails were cut off, and it was time to grind/sand down the epoxy plug.

Once the surface of the plug was flush with the deck, it got drilled and tapped for 10-24 stainless screws.  The remaining wire also got drilled out in this step, so as not to cause a corrosion problem down the road (the second reason why the wire tails were located exactly where the screw holes would later go)

Finally, it was time to screw in the eye-strap.  A little 3M 4200 on the screws to seal the holes, and that’s it!  Of course, I forgot to take a picture of the finished product, but it looks great and feels rock solid. 

This first time took almost an hour from start to finish, but now that I’ve done it once, I think I could cut the total time required to maybe 15 minutes.  For hardware like the eye-strap I mounted here, I probably will also have to paint the small exposed epoxy area for cosmetic purposes and for UV protection.  For other hardware like cam cleats and cheek blocks that I need to install next, I plan on cutting the slots so they will be completely hidden by the hardware once it’s mounted, so the end product will be completely invisible.

Thanks again, Brian Bennett for the process.

First sail on the Viper 640

This past weekend we finally launched the Viper for the fitst time. 

After several hours on Saturday getting the new carbon mast stepped, rig tuned (approximately) and a bunch of other little rigging projects done, we put the boat in the water in time for a late afternoon sail.  Many thanks to Charles and Dave for their help and patience as we got the boat ready to go.  (How many times did I say “wait, just one more thing”?)

 We had a nice sail in fairly light air on Saturday.  At first, we had 4 guys onboard, which was a bit cozy, but the boat really came to life in the light breeze with two onboard, when we dropped the other two guys off at the dock.   After getting off the boat, Dave K managed to get a couple of good pictures of the boat in the water (thanks for the pics, Dave!)

On Sunday we went out again after another couple of hours of additional setup work (fixing little things we’d identified during Saturday’s sail).  This time, the breeze was up, with wind in the mid teens, gusting to 25+ knots.  And wow…  did the viper move!  We didn’t fly the spinnaker, since I still need to finish setting up the running rigging for the kite, but even with main & jib only, we were easily popping up on plane and taking off on some screaming reaches.  Fun stuff!  

We managed to put the boat on its ear once when I didn’t react quickly enough to a huge puff (operator error!), but the boat behaved very well, sitting there with the leward rail in the water until we eased sheets, at which point it settled back down and we were off and running again.  All in all, much fun was had!

Got a new boat!

You may know that we sold our Capri 22 keelboat last year, and had been looking for a new race boat.  I settled on a Viper 640 sportboat as the ideal blend of speed, simplicity, and family-friendliness (in lighter air).  After months of searching for a used Viper, I finally struck a deal with an owner in Phoenix, Arizona, and a friend and I headed west to pick up the boat.

It turned into quite the epic roadtrip.  The seller had agreed to meet us in El Paso, TX (about halfway between Austin and Phoenix) to deliver the boat, but he was running late, so we ended up going all the way to Las Cruces, New Mexico to meet him.  All in all, we drove around 1300 miles in 20 hours.  Here are some pictures from our adventure:

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2008 Bridge Too Far Regatta - GPS Replay

Last weekend was the Stillhouse Sailing Club “Bridge Too Far” Regatta, an annual long distance race (20+ miles!) on Lake Stillhouse Hollow.  Dave K. and I sailed it on my Laser2 dinghy, Pterodactyl.  Click on the link below to view an animated replay of the regatta:

Download: 2008 BTF Replay
(Will launch a java applet in a new window. See the bottom of the replay page for hints & tips on using the player)

The replay includes tracks for the following motley collection of Texas Centerboard Fleeet Sailors:

• Mike M (Contender Dinghy)
• Steve W (Sunfish)
• Jim B (Sunfish)
• David L and crew (Flying Scot)
• Felipe P & Dave K (Laser 2)

We did ok on the first leg, which was downwind so we could fly the “Big Purple Monster” asymetrical spinnaker on the turbocharged Laser 2.  Sadly we only got to fly the kite on that first downwind and one other short leg.  We were a bit underpowered and overweight for the Laser2 when not flying the big kite, so Mike in the Contender, Rick P in his MC Scow, and David & crew started pulling away from us on the upwind & reaching legs.  We ended up 4th across the line and 6th on handicap, but still had a wonderful time.

Thanks to DaveK for putting up with my driving and constant fiddling for several hours, and to the Stillhouse Sailing Club folks for hosting a great event!

 David Luckenbach has a good writeup of the race with photos and videos on his excellent SailingTexas web site HERE.

GPS VMG Waypoint Circle Generator

This Excel-based utility lets you set up a GPS receiver to calculate VMG (velocity made good) relative to a desired heading, to help you fine tune your sailing angles (choosing between pinching and footing upwind, and heating up vs. soaking downwind). 

Essentially, this tool will generate a circle of waypoints centered around your sailing area, but several hundred miles away.  By uploading these waypoints to your GPS receiver you enable “VMG relative to a heading” functionality, similar to what is available on the ultra-cool Velocitek SC-1.  As long as your GPS receiver can calculate VMG to a waypoint, and you can upload waypoints to it from a “.gpx” file, you should be able to use this tool/hack to improve the sailing usefulness of your GPS.

Download: VMG_circle_waypoint_generator_B4.xls
(requires Microsoft Excel 2003 or later to run)

How does it work? Why is this better than simple VMG towards a mark? See the FAQ.

Screenshots:
 

Please note:  while this tool allows you to configure your “standard” GPS to approximate the VMG functionality of a Velocitek SC-1, it is NOT meant to replace or compete with the Velocitek. If you use this tool/hack, and like the “VMG to a heading” functionality, you should consider upgrading to a Velocitek SC-1, which will give you “VMG to a heading” in a much easier to read display, plus many more useful features, and a more rapid refresh rate (2x per second, compared to most GPS receivers which only update 1x per second). Oh, and FYI… I have no relationship whatsoever to Velocitek.  I just like their product!

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Lat/Lon Format Converter

Latitude/Longitude Format Converter

Have you ever suffered the frustration of having to manually convert a latitude/longitude between degrees-minutes-seconds and decimal degrees, or degrees with decimal minutes?

Different GPS receivers, maps, web sites, and documents will express lat/lon in one of the three formats above, and while it ain’t rocket science, it can be tedious to manually convert from one format to another, given that you have to go to and from base-60 (minutes, seconds) to base-100 (decimals).

The little spreadsheet below was created to simplify that process. It’ll let you enter a latitude or longitude in any of three formats, and return the latitude or longitude in any of the other formats.

Download: lat_lon_format_converter.xls

Screenshot:

Goodbye Condor

Well, it’s a bittersweet moment.  After three years of enjoyment, we’ve just sold Condor, our 1986 Capri 22 sailboat.  We had some great times on that boat, learned some lessons, and even had a couple of close calls (stories for another time).  Now, it’s time to move on. 

The plan now is to find a boat that will be more fun to race (meaning FAST!), while at the same time still providing a good platform for family daysailing.  I’m looking for a Viper 640, but the hunt for a used one is proving difficult, as the boat has experienced a huge resurgence of interest in the last couple of years, driven by an enthusiastic class association.

Taping and tabbing

After a long hiatus due to the day job (too much travel!) I finally had some time to make progress on Sarah’s boat. First, I got the boat flipped upside down (easier said than done for one person… it’s light, but BIG!), so I could apply duct tape to the outside seams in the hull. The tape is in preparation for the next steps, where we’ll be applying thickened epoxy to the seams. The tape will keep the epoxy from drooping out of the seams, helping save on epoxy, and even more importantly, cut down on the sanding required to the seams once the epoxy cures.

Next, it was time to start tabbing. In this step, you essentially create “spot welds” or tabs along the seams in the hull, using epoxy thickened with wood flour. You put the tabs alkong the seams between panels, in the gaps between zip ties. After the tabs solidify, you can go back and cut out all the zip ties, leaving the tabs to hold the hull together. This way, when you complete the epoxy fillets along the seams, and then cover those with fiberglass tape, there won’t be any zip ties along the seams to get in the way.

Finally, here’s a shot of the hull where you can see the epoxy tabs completed (the darker brown spots along the seam between the bottom and side panels.) The string you see in the picture is helping pull a little bit of twist out of the hull before I tabbed it all together, so I don’t end up gluing the twist permanently into the boat.