Designing & Building Hammerhead

The friendliest place on the web for anyone who enjoys boating.
If you have answers, please help by responding to the unanswered posts.
I would suggest designing a mast to enable a Starlink dish at some point in the future.

Kinda hard to do in that there have been two dishes so far, so who knows what will be required to support a Starlink marine dish in the future. At least make sure there is room for the wiring run.

Or figure out a place where the Starlink dish would go away from the mast.

Later,
Dan
 
Last edited:
I agree Dan. I am anticipating StarLink to provide an internet/connectivity solution, well, basically globally. At least by the time the boat is ready to sail, say 2 years from now. We'll prep for that.

Regards, Edwin.
 
@TT how good is the satellite coverage in extreme high latitudes, like the Antarctic Peninsula or the NW Passage?


The mini VSat maps show coverage for most, if not all of the NW passage, but I wouldn't bank on it. And they don't show any coverage for the Antarctic Peninsula. That where Iridium is really the only option. But I was thinking about the time one would spend outside those regions where there is good coverage, and full function internet might be desired.
 
Website & learning how to dive ...

We'll put a link out of our new website on February 8th, when it will be launched!

Here's a picture of the concept we are currently doing the last bits of work on. It deals with the LM65h, our story, the services we intend to offer, and a blog. For a first impression, please see the picture attached.

Regards, Edwin & Veronika.

PS: We are off to Curacao for a 10 days vacation starting mid next week. Very exciting, since we'll learn how to dive!
 

Attachments

  • Schermafbeelding 2022-02-03 om 22.19.46.jpg
    Schermafbeelding 2022-02-03 om 22.19.46.jpg
    101.8 KB · Views: 20
Last edited:
In discussions of HVAC think effective ventilation should be taken into account. Last boat had multiple large Dorades well placed. This allowed excellent ventilation even with sunshades down and everything closed. When others were running AC 24/7 ours was off. Also making a boat too tight is unhealthy even with filtering systems. We did crack the dorades a smidgeon open when the furnace was running. You transpire a fair amount. Between that and cooking having some circulation allows a pleasant environment. Know you’ve been most thoughtful but haven’t seen the delineation of ventilation in your plans posted. Hence respectfully mention this.
 
In discussions of HVAC think effective ventilation should be taken into account. Last boat had multiple large Dorades well placed. This allowed excellent ventilation even with sunshades down and everything closed. When others were running AC 24/7 ours was off. Also making a boat too tight is unhealthy even with filtering systems. We did crack the dorades a smidgeon open when the furnace was running. You transpire a fair amount. Between that and cooking having some circulation allows a pleasant environment. Know you’ve been most thoughtful but haven’t seen the delineation of ventilation in your plans posted. Hence respectfully mention this.

Professional Boat Builder(PBB) magazine has some articles on calculating air flow needs. :thumb:

On the epic, must read discussion, on specifying details on a boat build, https://www.cruisersforum.com/forums/f47/bestevaer-49st-147499.html, there was a long conversation about ventilation. The owners did not put as much ventilation on the boat as many, including PBB, would suggest.

That discussion was an eye opener. The boat in question has 3 inches of insulation which might make a difference in the need for cooling ventilation. Other insulated AL boat owners also said they needed less ventilation than one would think.

Twas a curious and interesting conversation. Well, the whole, long discussion was interesting but the part of ventilation was even more so. :D

Later,
Dan
 
Thanks for sharing! Important topic. I'll dive into this topic a bit later. I think we found a nice solution that both warms and cools. From a very reputable party.

Can say we didn't choose dorades (low positioning on a low profile boat like ours seems not ideal), but a forced system that allows us to ventilate very well with everything closed. Needs to be able to do that so she can recover from capsize.

Focussing on launching the website now. And doing that ahead of a little Vitamine D Holidays on the Dutch West Indies. If all goes well, we'll leave in a few days.

Regards, Edwin.
 
Last edited:
Heating/Cooling/Ventilation

Here's a picture of the heating/cooling/ventilation plan. For the various decks and rooms.

Regards, Edwin.
 

Attachments

  • Schermafbeelding 2022-02-07 om 09.44.46.png
    Schermafbeelding 2022-02-07 om 09.44.46.png
    120.9 KB · Views: 33
Thanks! Not yet, Twisted Tree. We are currently in the process of obtaining various quotes and investigating various shipyards.

Regards, Edwin.
 
Last edited:
Salty Edwin, was just noting that with the low profile of your vessel, that cowls/dorades would probably be very effective.

Even though you’re focusing on forced ventilation of habitable spaces, you may wish to install intake / exhaust cowls for the lazarette, chain locker and undersole (bilge) of the stateroom area. Keep things fresh and mold-free.
 
Thanks for sharing! Important topic. I'll dive into this topic a bit later. I think we found a nice solution that both warms and cools. From a very reputable party.

Can say we didn't choose dorades (low positioning on a low profile boat like ours seems not ideal), but a forced system that allows us to ventilate very well with everything closed. Needs to be able to do that so she can recover from capsize.

Focussing on launching the website now. And doing that ahead of a little Vitamine D Holidays on the Dutch West Indies. If all goes well, we'll leave in a few days.

Regards, Edwin.

Exactly, and as that NZ boat recently mentioned does. And its not just heat/cold/ ventilation, but now you can get mold removal, etc & filtering for those who get alergies, from smoke from local fires, etc. They even remove the salt from the air, so electronics last longer. Modern hvac systems do everything, and a nice boat like yours should have it all.
I like your points about no dorades too, since your boat is Gz, 180, it should be totally sealed.
 
Last edited:
I understood that dorades, situated on a low profile boat like us that has a narrow build and quite some spray over the bow, aren't the best solution.

Keen to hear you guys' opinions on this.

Not sure what Gz means?

Regards, Edwin.
 
Last edited:
A low profile boat with small frontal area and low structure should have smoother airflow and less turbulence. That should work in favor of cowl vents.

The dorade boxes trap water and spray so they don’t get below. In any case I’m referring to your storage areas and bilge, so even some condensation drips won’t have any effect with lots of fresh ventilation.

Of course you’ll need to rely on your NA’s judgement and experience.
 
Gz refers to the standard way to plot the stability curve. Want it to intersect null at at least 130 degrees and have the smallest area under null as possible so the vessel self rights quickly. Want it to show the boat is unstable when inverted and will self right with just modest wave action. Getting a small area under null is easier with a narrow boat not depending upon form stability for its righting arm. So suspect you won’t need escape hatches like multihulls:).

https://www.marinesite.info/2021/04/gz-curve-or-curve-of-statical-stability.html

In gale or storm conditions simply closed the dorades from below. Also most dorades allow you to remove the cowl (just unscrew it) and replace the hole with a threaded plate. Lastly most folk aim the forward cowls to aft and the aft ones forward. Never seen spray as an issue. To prevent green water or spray from entering is the reason for dorades.

Excellent point about ventilation below all areas below the sole not just the ER. Would think that remains true in metal boats both Fe and Al.
 
Last edited:
Thanks for the explains. Yes, we (NA) did a lot of testing and research on the ship's stability. And it is self-righting.

NA wasn't in favor of dorades. We'll have bilge pumps in stern and aft lazarets. I'll discuss ventilation of those spaces later, as molding is something I don't want, for sure.

Thanks!

Regards, Edwin.
 
We both finished out PADI Open Water Diver Course. Well, the theoretical part of it. The practical training will be next week. We want to learn to dive because it can help us inspect the boat, the anchor, etc. Also, as we will travel the world, there for sure are going to be beautiful diving locations to be visited.

Regards, Edwin & Veronika.
 
Good idea Salty Edwin. Get certified and obtain a Third-Lung type air source so you can scrub your boat's bottom regularly.
 
Working on the mast and antenna lay-out ...

Well, the NA's are. We are enjoying some Vitamine D time on Curacao!

Regards, Edwin & Veronika.
 

Attachments

  • fbab48cf-766b-464f-a736-28a845fbe829.jpg
    fbab48cf-766b-464f-a736-28a845fbe829.jpg
    111.3 KB · Views: 23
Here's another picture of the mast lay-out. Radar, VHF antenna's, Flir, augmented reality, horn, wind instrument, iridium. White nav light and anti-lightning rod on top. GPS and AIS as well, of course. And integration with augmented reality. I'll post a pic tomorrow on how that looks.

Mast and antennas can be folded forward to lower the overall max height above the water line of the ship to 3m40. Anything under 3m50 allows those wanting to cruise Europe's inland water ways, to the extend of being able to cross the continent from the North Sea to the Med (or back), via the canals and rivers of the Netherlands, Belgium, Germany, and France.

This way, our design complies with Beebe's original long-distance motor yacht cruising philosophy: you want to be able to cross oceans so that you can cruise the places you visit. If I remember correctly, he even gave the above example. "Sail your motor yacht to Europe, then use your yacht to cross France via it's channels." Or words close or equal to that.

To that extend, and making use of modern communication and navigation aids, I decided to go for a relatively low mast/radar/etc. set-up, in terms of height. And I proposed to our NA that we should make the mast fold forward to achieve a wider inland cruising capability.

The maximum beam of 5 meters of the LM65h design also supports the more narrow lock designs one finds inland. France's inland locks, for example measure, 5m10 in width. Yes, fenders won't fit, but mats do and that's what the 5 meter wide standard professional barges use.

Regards, Edwin.
 

Attachments

  • 05961080-88eb-41bc-92d2-1e8f7bbf548a.jpg
    05961080-88eb-41bc-92d2-1e8f7bbf548a.jpg
    94.8 KB · Views: 21
Last edited:
Salty, regarding the folding mast point, more evidence that this will be a really good boat! Those European canals are wonderful!
 
Here's a picture of the LM65h. I personally love the addition of the dolphin seat at the front!It can be used for forward faced seating as well as backward faced seating.

Regards, Edwin.
 

Attachments

  • 1035fc61-c202-437d-8518-a8deebb432bc.jpg
    1035fc61-c202-437d-8518-a8deebb432bc.jpg
    98.5 KB · Views: 21
Ah, a Caribbean update! Diving class starts the day after tomorrow. But we have been snorkeling. Today, we snorkeled with turtles!

And, well, I am here with my family in law, and they love to cook. But, since turtle soup was off the menu, we bought a freshly caught 5 pound tuna, directly from the fishing boat.

My brother in law turned most of the fish into filets that will meet the BBQ shortly. My wife's uncle, Ome Joop, turned the remains in an (almost) Hungarian fish soup. I guess we (they) are changing the Caribbean kitchen fundamentally, during our visit! :)

All the best to y'all. Thanks for keeping up to date with our posts and for giving your feedback so generously.

Regards, Edwin & Veronika.
 

Attachments

  • f350b1f2-eaf8-4710-854e-8e48f20ce056.jpg
    f350b1f2-eaf8-4710-854e-8e48f20ce056.jpg
    127.1 KB · Views: 11
Last edited:
We are about to start our second day of diving training. First day was interesting, full of exciting learning and exercises, and pretty darn tiring ...

Regards, Edwin & Veronika.
 

Attachments

  • 237294b3-60ee-495e-9185-d71feb75b049.jpg
    237294b3-60ee-495e-9185-d71feb75b049.jpg
    119.5 KB · Views: 22
Forepeak design & lay-out

With Veronika and me obtaining our PADI Open Water Diving diploma, the NA's are working on the forepeak lay-out. The forepeak sits just behind the anchor chain locker and we plan to use it to store bigger yet secondary equipment. Ladders, extra anchor, davids ... and - yes - diving gear!

Here's picture/schematic of the room, with a starboard perspective.

Regards, Edwin.

Regards, Edwin.
 

Attachments

  • 410e47a8-dc89-4004-8169-4643d64e756e.jpg
    410e47a8-dc89-4004-8169-4643d64e756e.jpg
    165.9 KB · Views: 24
Back
Top Bottom