I have just been handed a boat design challenge

[Gib Etheridge]

Yeah, I saw that Jim, but it's not actually bulbous. It's more of a standard fat hull with a big dent in the stem just above the waterline. It certainly made me wonder though. It's too bad the 1/2 on each side would be so expensive to tank test. There have been some that don't extend way out forward but still alter the bow wave enough to enhance efficiency. I expect that the shape shown is meant to do the same, and that a whole lot of money went into development.

[mmd]

Gib, if you are referring to the brown crab boat a few posts back, it was designed in France and (I believe) extensively tank-tested. Construction Navale Atlantique has several hull sizes, all based on the same hull form, ranging from (IIRC) 36 feet through to eighty feet.

[Gib Etheridge]

Michael,

If half were applied to each side there would not need to be any alterations to the inside.

I just spent some time studying bulbous bow history, function and engineering. Jesus. I'm glad I don't have to do that kind of stuff. I'll just build my simple kind of stuff and hang out with the wildlife thank you, but I do like the idea of me presenting the idea and you doing the work.

Here's a bulbous bow that I can actually identify with.

Panasonic FZ300 camping 2018 001.jpg

[Gib Etheridge]

Gib, if you are referring to the brown crab boat a few posts back, it was designed in France and (I believe) extensively tank-tested. Construction Navale Atlantique has several hull sizes, all based on the same hull form, ranging from (IIRC) 36 feet through to eighty feet.

Yeah. Chas is Jim.

And not to change the subject too much, but we now have a reported case of Covid on Salt Spring. You still coming?

[mmd]

Plans are in flux right now, Gib. We are definitely coming out to the West Coast, but due to the recent spike in cases in the greater Van area, we are changing the itinery. Whistler Peak-To-Peak gondola ride is out, a few days in Tofino is in. A day in Victoria and high tea at the Empress is out. I am still lobbying to find a way to come visit you for at least a brief elbow-bending session, but logistics are tough. We are having a Zoom meeting with the kids tomorrow (we depart on Tuesday) to hammer out final details, & I will send you an e-mail to update you.

Damned virus...

[mmd]

Well, there goes one idea...

The manufacturer of the box cooler has no experience in installing one in an FRP boat and doesn't want to start with my project. So it's grid cooler or "the way we always done it". Phooey.

[Gib Etheridge]

So perhaps you can design your own? How about this? It get's bolted to the side(s) of the keel. Better yet, eliminate the inner face, which is to say make it into a wide channel with a baffle down the middle, and gasket it to the keel. The ends are faired in, that should help, and it's very little increase in the drag of the keel, certainly much less than the pipes, plus it's easy to remove and clean when the boat is hauled and low tech as well.

keel cooler 001.jpg

Could be the heat would affect the glass keel.

[mmd]

Nope. I could design a cooler, but with the amount of money at stake if something went wrong, neither I nor the builder would be prepared to warranty the product. It has to be 'store bought', tested & approved by a classification society, etc.

I'll be meeting with the gbuilder on another project tomorrow, so we will discuss having the hull molded with recesses for Fernstrum Gridcoolers.

[Gib Etheridge]

Ah well, I'm out of ideas. Sorry.

[nedL]

I’m certainly in for following along.
At a small shipyard I worked at decades ago they built boats (commercial -steel) with boxed in keels for the FWC as Gib was mentioning. Nice in that there are no drag or barnacle considerations. Certainly understand why it is not an option here.

[Paul Schweiss]

Really enjoying this thread! I especially like how you have sneakily enlisted the brain power of Forum members, getting all kinds of ideas for free!
’Course whatever ideas you may use will still have your name...and reputation attached to them.
Great thread to show both the Design and Commercial sides of this syndrome we call Boatbuilding.

[Hwyl]

Really enjoying this thread! I especially like how you have sneakily enlisted the brain power of Forum members, getting all kinds of ideas for free!
’Course whatever ideas you may use will still have your name...and reputation attached to them.
Great thread to show both the Design and Commercial sides of this syndrome we call Boatbuilding.

I think we’re getting much more than giving. In fact I think the only role we are playing is that of a sounding board. I’m grateful to Michael for sharing his experience.

[Garret]

I think we’re getting much more than giving. In fact I think the only role we are playing is that of a sounding board. I’m grateful to Michael for sharing his experience.

He does a lot of that & I too am grateful.

[Stiletto]

He does a lot of that & I too am grateful.

Yep, me too!

[mmd]

Sorry that I am 'laying low' right now, folks. I actually said to hell with Covid paranoia and am taking my first actual vacation in about four or five years. I am currently in Vancouver and will be heading to Tofino for a few days on Sunday. Having a lovely - and socially-isolated, masked, slathered-with-antiviral-goo - visit with my daughter and her beau. Went for a drive up the Sea-to-Sky highway today, took the S-to-S gondola to the top of a 1200-metre mountain and spent the day hiking in high places, and am about to go to Gwyn & Isaac's place here in Van in a few minutes for a BBQ. I will be back in Nova Scotia next Friday night and will catch up on developments in this thread over that week-end. Lots of smoke here from the USA forest fires, so not the best for scenic photography, but a helluva lot better than some have it on the West coast. Stay safe, and now go wash your hands... <grin>

[Hugh MacD]

Sorry about the smoke, Michael! The view from the top of Grouse is spectacular and I hope you didn't miss too much. Smoke was thick enough here (near Portland, Or) that we couldn't see the sun. Glad you're out of that!