Buttocks

Is that more tea Mr. Braithwait? ....

 

I am most gratified!

 

Eureka! I'm afraid I must leave it to the reader to imagine me running down the street naked, trailing bath water like Archimedes. My original conundrum was why the bottom chines which defined the port and starboard sides of the inverted v tunnel in Hickman's Sea Sleds curved inward towards each other running aft. The Patent Drawing that Ad Hoc was generous enough to include in the first response clearly shows that Hickman was still doing this in 1945, and in fact his patent description talks about the loss of lift as water flows laterally across that chine, out of the tunnel on to his previously patented non-tripping chine.
So I ordered the building plans for the TX18 from bateau.com. The TX18T is a modernsea sled, optimized as a fishing boat for the Texas Flats. The plans included the lines for a Sea Sled drawn by a fellow named Jackson, around the time of Hickman's death.
In both cases those troublesome bottom chines diverge going aft, by exactly ¾ inch over every 3'. I am pleased that my non-numerical visualization was sufficiently accurate that I correctly identified a design issue, and that I was so certain of it that my great esteem for the late Mr Hickman wasn't enough to silence it. It would have been easy to simply say "Hickman invented it. Obviously he knew better than I ever could. I should humbly shut my pie hole. Also he was probably better in bed than I am."

And now time for physio. I dislocated my shoulder, patting myself on the back.

 

Okay. That sounds like I was pretty pleased with myself. Really, I'm happy that I know what to do next.

I've got an idea for a pretty affordable large scale tank, unless CFD has gotten so good that tank work is irrelevant these days.

 

You are a victim of a cult, I fear. You say you know of a fella that has built a number of alloy sleds, but what were they actually used for ? Does not the fact that the type is almost invisible in the marketplace, concern you ? If such a winner, people would have voted with their cheque-books. I wouldn't touch them, because I fear they could be a kidney-relocation device !

 

I'm grateful for your concern. I'll spend a year on it. Considering I once wasted 17 years on a bad marriage, a year seems pretty trivial.

And if my kidneys get bashed loose, I'll let you know!

 

As Ad Hoc says, carefully set out the requirements of the duty of the boat ( you may have done so, somewhere) and that would be a starting point to getting the right "ship" for the task, rather than just starting with the idea it must be a sled. A catamaran may be a better proposition, and especially in your are going to encounter any kind of chop.

 

John, what are your thoughts re the Munson cats?

the Incredible Munson Hull | Custom welded aluminum boats, landing craft, workboats, patrol boats, fire boats, passenger boats, dive boats, research boats, fishing boats, boom boats https://www.munsonboats.com/newhulls.php#more3

 

Looks like their welding and construction is absolutely first rate. Love the deck plans and conceptual work in general. That catamaran is going to slam like an early Ministry album though. Mr Efficiency would not approve.

 

Just test drove a 28 foot Axopar with a 300hp on it.
Seas were 1' - 2' chop with some ferry wake.
Quiet, smooth, fast, thirsty.
Quality feel, easy to drive.
Excellent visibility and comfortable with five people on board.
Vinyl-ester.
CAN$228 000 plus tax.

I know it's thread drift but DogC is local and the boats are being sold here as commuters.
It's a nice, protected ride.

 

Re the Munson cats, I wonder if they also create a compressed cushion of air between the hulls to help soften the ride?

Re BlueBell's 28' Axopar, here is a link to the Builder's webpage re the T-Top version - they also have 'Open' and 'Cabin' versions.
Axopar 28 T-Top https://www.axopar.fi/range/axopar-28-t-top/
They say that the 'starting' price is from 45,000 Euros, but I guess that this is without an engine.....

There are a couple of 28's and a 37 here in Barbados - they do seem to be very nice boats.

 

Thread drift is fine at this point: we've answered the question to my satisfaction.
Fellows, those boats are completely outside my budget. If I want a boat like that, I'll have to build it myself. I have some of advantages: this crew of brilliant advisors; my own 34 years of building things; a good shop; free wood. Disadvantages: a full time job; an ex-wife and autistic child who take so much of my income that buying such a boat is impossible.

 

Thanks DogC.

I wasn't suggesting you buy an Axopar, no more than I was considering buying one myself.
I thought it an interesting design for our waters.

So, given your last post, the most economical way is to buy a used boat that meets your needs.

Have you considered a jet-ski?
Fun, fast and seaworthy!

 

My SOR, as I've learned to call it, is
Carry a dozen workers and their tools; land on a beach; provide dry living space for 2; go fast; be attainable

And, be a sea sled, for reasons that aren't 100% objective.

 

Maybe a vessel like this would work for your SOR?
Trouble is, she is a tad expensive.
https://www.pacificboatbrokers.com/used-boats-for-sale/WA5343/new-landing-craft.asp

Here is a heavy duty 32' aluminium boat with a little cabin - however she has a pair of thirsty I/O petrol engines.
You could perhaps chop the bow off and put a landing craft style bow ramp on instead?
1975 Carlson Bowpicker Power New and Used Boats for Sale - www.yachtworld.co.uk https://www.yachtworld.co.uk/boats/1975/carlson-bowpicker-3575123/
She is $25,000, but I doubt that you would be able to build a new boat yourself for that amount (?)

If you could build a 'cheap' Sea Sled version of this, then you would be on to a winner.
2015 Munson Packman Power New and Used Boats for Sale - www.yachtworld.co.uk https://www.yachtworld.co.uk/boats/2015/munson-packman--3492284/