A comparison of the Lindsay and Hamlin/Waterat hull Shapes

I have owned and racing Waterats since 1983 (I bought the first plastic Waterat), but recently acquired and raced two older Lindsays hulled 5o5s, both rebuilt by Waterat Sailing Equipment. Since I was very familiar and comfortable with the standard Waterat layout (both my Waterats are only slightly modified from Waterat's basic rigging layout), I had Waterat re-rig both Lindsays with a very similar layout. I used Waterat foils, a Proctor D mast and the same sails I use on my current Waterat. Lindsay 6987 weighed in all up about 5 kilograms over - though that was with a heavy spliced mast - about what my first Waterat - 7772 - weighs. Lindsay 7200 is actually a Lindsay hull finished by Waterat with oak veneer on the tanks, and a different thwart layout. 7200 is slightly overweight, though by less than 6987 or Waterat 7772. All are within 10 pounds, a difference that I believe is not noticeable. I raced Lindsay 6987 at the 1995 Canadians and North Americans, and 7200 at the 1996 Townsville World Championship and the '96 UK National Championships. The Lindsays felt quite different to the Waterats I was familiar with. This article discusses the differences - subjective - that I noted, and some of the actual measurement and shape differences that may cause the different feel of the boats.


The Lindsay hull shape was developed in 1977 by Mark Lindsay Boatbuilders. A micro balloon plug was built and then shaped and faired to get the new shape. Larry Tuttle did much of the work shaping the plug for the Lindsay hull mold. At almost the same time, Howard Hamlin drew up the Hamlin hull shape, and built a plug and then a mold in early 1978. Waterat began building boats using the Hamlin tooling in 1983. While Waterat has made changes to the deck mold, to the structure and to the layup schedules, the hull shape has not been changed; Waterat hulls are the same shape as Hamlins.

Lindsays, Hamlins and Waterats are all fully cored, epoxy layup boats. Though different types and weights of cloth have been used in the skins, and several different core materials have been used, the results are similar, a stiff very long lasting hull. This article will discuss the shape differences, and ignore any possible effects due to construction, as I consider them to be minor and they do not effect feel. A possible exception is that the current Waterat hull shells are built lighter than either the Lindsay or the Hamlin hulls. When completed, the Waterats have more weight in the center of the boat, and are therefore lighter in the ends than the original Lindsays and Hamlins.

Both the Lindsay and the Hamlin/Waterat hulls have been very successful at the National and International levels. Lindsay hulls won the '81 and '82 Worlds, and have been close several times. The Hamlin/Waterat hull shape has not won the worlds, but has been close on several occasions. I expect that Lindsay or Hamlin/Waterat hulls have won every North American championship since about 1979.

Subjective Comparison

The Lindsay boat feels heavier in the water. It seems to react very slightly slower to body or tiller movement. It feels less lively than the Hamlin/Waterat. In the light and medium air conditions of the '95 Canadians and North Americans, I felt that I had to start a course alteration a little earlier, and do it a little more slowly than I would have in a Waterat. The Lindsay also felt slightly heavier on the helm than the Waterat.

In the 20+ knot breezes of the lay day between the Canadians and North Americans, the boat felt slightly steadier and smoother on the reaches than a Waterat. To use a technical term, the Waterat is a little more twitchy than the Lindsay. The Lindsay seemed to go faster when planing with the chute up when we sat further back in the boat than we would have with a Waterat. The bow of the Lindsay comes up higher when planing that does the Waterat, though this could in part be due to our sitting further aft in the boat.

The higher tanks of the Lindsay result in significantly less water being shipped on roll tacks. The slope of the top of the Hamlin/Waterat tanks results in most of the water that comes over the rail ending up in the bottom of the boat, while most goes back out over the rail in a Lindsay. The different tank shapes alter the way the skipper hikes - I found myself loosening the straps in the Lindsay more than I would in the Waterat. When sitting on the tanks, you may be sitting very slightly higher in the Lindsay.
In the predominantly light and medium air, shifty conditions of the Canadians and North Americans, we felt our speed was often quite good, but sometimes inconsistent. Without going into detail, we were about as fast as Robin Brown/Dave Thomas, and almost as fast as Howard Hamlin/Mike Martin upwind in several races. Brown/Thomas raced a Hamlin, Hamlin/Martin a Waterat. We occasionally felt we were off the pace, but ascribe that to being unfamiliar with the slightly stiffer D (an old section with several reinforced areas, and being unsure of exactly how much mast bend we should be carrying - the different ram setup meant that I could not eyeball mast bend by seeing where the ram car was relative to the the gooseneck, as I do with Waterat 8263. I did not notice speed differences that I could ascribe to hull shape. One possible exception was that we were able to gain or even pass Hamlin/Martin and Brown/Thomas on a couple of occasions on very light air runs. Was that hull differences, John Fry flying the chute, our using a North Power Chute, gybing first and being inside, or just luck?

I raced 7200 at the '96 Worlds and '96 UK Nationals. At the Worlds, I raced a boat that I had never sailed, and had seen once in 1981. Mike Mills, who I had never sailed with before, was crewing. Conditions were lightish, Mike often wore weight, but it only blew hard enough to plane upwind for two windward legs. Our speed was fine, but our pointing was suspect, we also felt vulnerable on reaches with the North Power chute, and better but not great, with the Fisher North chute. We finished 27th overall, feeling that our boathandling was not great, and our speed not optimal. I suspected that much of our upwind problem was jib sheeting, as I was not confident I was sheeting the jib at the same fore-and-aft angle that I would on 8263.

For the UK Nationals, we used trim lines on the jib to get the jib lead close to the same angle as 8263, and used the new North spinnaker design. WOW! In the windier conditions of the UK Nationals, we were up with the fast boys. I think we rounded the first weather mark in the top ten in almost every race, and were as high as 4th at a first mark. Our reaching speed was excellent, and running was not bad at all. Boathandling again was a problem for us, and three capsizes, sailing over the spinnaker sheet, twisting the spinnaker in knots on a gybe and ingesting the spinnaker sheets through the mainsheet ratchet block conspired to have us finish every race but one outside the top ten. Our worst finishes were two 20th places, in a 75 boat fleet.

7200 felt steady upwind - it did not want to heel quite as easily as a Waterat, and may have been smoother through the waves. It appears to be easier to bury the bow of the Lindsay compared to the Waterat. We never really planted it, but got the rail at the bow close to water level more frequently than we do with 8263.

Some Measurement Similarities and Differences

I believe both the Lindsay and the Hamlin/Waterat are minimum width on the waterline, at every station.
Both hull shapes seek to reduce rocker, and are close to the minimum allowed by the class rules. Rocker is more or less evenly distributed with the Hamlin/Waterat, while the Lindsay puts most of the rocker underneath the mast step.
Underwater Sections
While both hull shapes are minimum width at the waterline, the bottom sections below the waterline differ somewhat. The Lindsay is flatter in the middle and then more rounded near the waterline, while the Hamlin/Waterat is more veed. Imagine a "V" and a "U" that are the same width at the waterline.
Above the waterline the Lindsay flares out to maximum width quickly. This has the effect of straightening some of the reverse curve that forms the 505's distinctive flare.

How the Shape Differences Could Account for the Feel Differences

Hamlin/Waterat Rocks More Easily
The transition from minimum width at the waterline to maximum width above the waterline in the Lindsay hull suggests to me that the Lindsay hull would have initially more righting moment as it heels (imagine both hulls heeled to ten degrees, and consider that the Lindsay is maximum width shortly above the waterline, so that maxiumum width would be immersed when the boat heels. This may account for the less twitchy feel of the Lindsay.
Lindsay Bow Higher When Planing
This is a bit of a stretch considering the limited time I spent planing around in the Lindsay, but if most of the rocker is underneath the mast step in the Lindsay, and you sit further aft, you would get the rocker out of the water, and would be planing on the flatter aft run of the hull.


Though they feel different, look different when carefully compared, and measure differently, both the Lindsay and Hamlin hull shapes are FAST, and probably fast enough to win the Worlds in the right hands.
By Larry Tuttle and Ali Meller