more questions about semi-v definition

jimmwaller

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more questions about semi-v definition. Trying to reconcile all the things I've read....

I have a '55 lonestar riviera. Was just reading about it on FiberGlassics, looking at old brochures and stuff. These lonestars are listed as semi-v boats. BUt then, on iboats, it sure seems like the consensus is to measure deadrise at the stern/transom. I'm pretty sure my lonestar has no deadrise at the transom. Maybe there's like a degree or two, but it's basically flat.

So, what am I missing? Is my boat a semi-v? The bow has some deadrise, but even still not a ton, but it's mostly flat. But the brochure says semi-v. Did they just use a different definition back then? Or....?

thanks!
 

Ned L

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I would think it breaks down like this. ..... When your boat was built the "V" and esp. The "deep V" hull form had not been developed yet . They started to come into play in the early '60's with guys like **** Bertram (and his Moppie), Ray Hunt, Don Aronow and the like. Until then most boats had very flat sections aft. When your boat was built, they looked at the shape of the forward sections, and ran with that for the term 'semi-V'.
 
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jimmwaller

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Hi Ned,

Thanks for the info. Makes sense, I figured there was just some explanation I was missing. Well, shoot. I've been kind of wondering why this boat wasn't really performing like how I would expect a semi V to perform, especially in small chop.

Since I'm a fairly new boater, I wonder, will I have serious performance limitations with a flat stern? I mostly just need to handle 1-2' chop sometimes and stay reasonably dry... with experience, do you think this boat is up to the task? Or should I be looking into getting an actual semi-V.

thanks!
 

Ned L

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You don't say how big your boat is, I'm guessing about 16ft. Quite frankly 1 - 2 ft chop is a lot for any boat that size. ...... And truthfully people often don't realize how big chop really is ( typically over estimating it). Two foot chop will keep most owners of boats twice that size at the pier.
That said,.... Yes, a newer hull form (dead rise all the way to the transom) will be more comfortable in a chop.
That will come with a cost of more fuel. The boat you have now is easier to get up on plane, and easier to push through the water, so it will also be easier on fuel.
 

JimS123

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Semi-Vs and Deep-Vs all have a V hull at the bow. This is in contrast to a Jon boat, for example, which has a square bow and a flat bottom.

A Semi-V has no V at the transom. The bottom is basically flat, with rounded chines. A Deep-V does have a slight V at the transom, and the chines could be round or hard (square-like).

You DO have a semi-V already.

I have two 14' aluminum boats. One is a deep and the other a semi. I do see a noticable difference in performance when the waves get bigger. The difference to me is more of comfort. With the right speed, both provide a dry ride. A 1' chop is no issue, but 2' is much less comfortable.

I suggest you try what you have and see how you like it. If it isn't satisfactory for you, going to a deep-V is probably not the answer - you just need a bigger boat.
 

jimmwaller

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Thank you both. To answer a few of the questions:
My boat is about 17'6", and you're right, it's probably about 1ft chop! ha. I almost certainly overestimate. And I'm not at all worried about fuel or speed, I really only use it for fishing, so most of the time I'm stationary. It's just the ride to and from the fishing spot that can be a bummer!

Thanks for the input on me having a semi-v. Although I must say... I'm now as confused as ever! It seems as if half the people out there say I have a semi-v, and the other half say, "you have to measure the v at the transom. So, since you have no deadrise at the transom, you don't have a semi-v". Ha! Clear as mud :)

more questions:
1. Is this boat safe to bring up to a plane in 1ft chop? Now that I'm thinking about it, the bow slams so hard into the waves, I wonder if I'm being unsafe planing it in chop.
2. If I do decide to get a bigger boat, assuming I stick with a semi-v (vee bow, but flat stern), how big of a boat are we talking to be able to stay dry in some chop? 20 feet? 22 feet? 25 feet? bigger?

thanks!!
 

Ned L

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A boat with a deeper "V" (and running all the way to the transom) will be more comfortable underway in a chop. It will also tend to roll more when stationary fishing.
 

Watermann

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To show you what's being explained is in the 2 pics below. Hope this helps.

First pic has a V bow but as you can see the stern is flat bottomed. I'm of the opinion that this is a semi V as the bow back to mid-ship has deadrise.

35098d1253148564-mystery-boat-help-me-dsc_1202-1.jpg



This one is the transom of my Starcraft I'm currently working on and as you can see the stern has a significant deadrise to it and would be considered to me as a V hull.

IMAG2191.jpg
 

ondarvr

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more questions:
1. Is this boat safe to bring up to a plane in 1ft chop? Now that I'm thinking about it, the bow slams so hard into the waves, I wonder if I'm being unsafe planing it in chop.
2. If I do decide to get a bigger boat, assuming I stick with a semi-v (vee bow, but flat stern), how big of a boat are we talking to be able to stay dry in some chop? 20 feet? 22 feet? 25 feet? bigger?

thanks!!


First, it makes no differences what its called, there is no rule when it comes terms, and most are first used as marketing hype, so don't stress over it. It is what it is.

1. Its not so much "is it safe", flat water can be unsafe, its can you handle the conditions in the particular boat. And if you can handle being beat up if the conditions get rough. Most boats can handle more pounding than the people onboard.

2. Use this boat and see if it works for you, then think about bigger. The bigger the boat the better it will tend to handle rough water, but that's just a general statement, and not always true.
 

dingbat

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The roughness of our local waters gave birth to the famous Chesapeake deadrise design. The deadrise is characterised by a sharp bow that quickly becomes a flat V shape moving aft along the bottom of the hull. The deadrise is a very capable rough water design.
The design is very popular in the 14' to 16' size for use as crabbing skiffs. Very seaworthy for a boat their size
 

steelespike

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We have had a 15' flat transom. LoneStar since it was new.
It tends to run bow high and at rest can be very unstable if you stand or move around
in the forward area.
I worked with a guy with I believe 16 or 17 ft. With a 60 or 70 hp I think it had a 15" transom
It actually sank on him with a max load a rough day trying to launch it.
It was flat at the transom.He never used it again.
I'm pretty sure they all were unstable in the forward area.
 

jimmwaller

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@ondarvr: Fair enough! Marketing hype, that seems to be everything. Remains to be seen whether I can handle the pounding. But I think I've decided that this boat can't handle what I'm trying to put it through, at least not with my current skill level. I'm fine in the mornings, but once the afternoon swells come up, which are usually about a foot, I do a lot of slamming and I get soaked on my way back to harbor. I probably won't get a new boat soon, but I'd like to keep my eye open for the right one. Given this, when people talk about making a significant "jump up" in size, what are they talking? I have a 17.5 footer now, will a jump up to 19 make a major difference? 21 feet? longer?

@dingbat: Looked up some chesapeake bay hulls?very cool.

@steelspike: when you say unstable in the forward area, it seems like you mean at rest. Does this translate to under way, as well? I have been feeling like it's a little squirrely, which could be attributed to riding high in the bow, but I chalked it up to my inexperience. Do you like your lonestar? What kind of conditions do you use it in? Is it similar to a riviera? Might help me to determine if it's more the boat's issue, or me just being an inexperienced boater.... :)

thanks!
 

southkogs

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We used to have a '58 Lake-N-Sea that wouldn't be terribly different than your Lone Star (how the hull was built). It was a little bit rocky when you were up and moving around. Underway, it was fine with this exception - when you really tried to turn it hard and fast (and it wasn't all that fast), you could really heel her over and almost dump a gunwale in the water. Felt scarier than it ever actually was, but it's was a quirk about that little boat.

I don't think the jump from a 17.5 to a 19 is too major (I just did that last year), but when you pass 22' or so the game changes a little. I think noticeable (maybe the best word) in the trailering/launching/recovering department and how it handles rougher water. I've been on the Gulf in rough water in a 19 and a 24 and I thought the 24 handled it very differently for being so similar a hull.
 

JimS123

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... I'm now as confused as ever! It seems as if half the people out there say I have a semi-v, and the other half say, "you have to measure the v at the transom. So, since you have no deadrise at the transom, you don't have a semi-v". Ha! Clear as mud :)

What's clear is that half the people you are talking to don't understand boats 101. Go to the library and find a book that deals with boat hulls. Then you will be able to splain it all to them. For the class of boat you are talking about its either one or the other - there ain't a common 3rd version.

Now you're talking about 1' swells. My little puddle jumper semi-V will handle that all day without getting wet. But then again we only have 9.5 HP so we don't go too fast. Maybe try slowing down a bit.

If you upgrade from 17 1/2 to 19 I think you still won't be happy. A 24 might suit you but now the cost of ownership and hassle of storage, launching and docking will go up astronomically.
 

jimmwaller

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southkogs: good to know, that was maybe what I meant. I am thinking about making the jump up to a 22' or so just for the rough water. Seems like it'll only help.

@jims123: Thanks for the info... it does seem like I'm getting a lot of mixed signals, even just on iboats. I guess if I could ask one question, it would be whether the hull shape at the transom matters. But this is mostly a semantic distinction. won't change how my boat handles, which is what I'm worried about now! ha.

I'll try slowing down. I feel like when I go slow, I run right into the wave face and then I get a little spray on me every wave, so by the time I'm back at the dock I'm soaked. But, when I go fast, I get over the waves fairly well, except then every once in a while I'll run right into a bigger wave face or something will happen where the spray just explodes all into the boat. So while this doesn't happen very often, it's so much water that by the time I'm back, I'm soaked! What are your thoughts on moving up to like a 22' or so (my dry storage has a 22' max for my space, with a tiny bit of wiggle room). I can't go much bigger than that, so if a 22' won't make much of a difference, it's probably not worth it. But if it will make a significant difference, seems like I might give it a shot.

thanks everybody!
 
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