Red Sea Dive Boat

Cheers BB!

Unfortunately very close to corals at times, and the water at what passes for a jetty is very shallow as well.

From what I understand, jets are more efficient too - which will be important to keep costs down.

 

I just researched your Yanmars and Doen jets.
This is a long way from twin outboards.
Government rules okay with this option?
I sure prefer the diesel over gas of the o/b's.
Only snag might be cost vs budget...

 

The coastguard has only restricted outboards - a fair bit of drug running happens in that part of the world so I guess they are targeting RIB's and other fast boats that hang outboards.

I prefer diesel as well for all of the obvious reasons.

I won't know cost until Doen reopen after Christmas.

 

I just ran through your previous equipment thread and noticed the the discussion about cutting left off in July with no real conclusion. If that is still of interest, Laser cutting may not be the best choice. Laser cutting has some limitations with aluminum due to thermal conductivity and reflectivity. Shining a light on a mirror is not the easiest way to warm it up. The maximum thickness for laser cutting is about 30 mm. There was some mention of water jet cutting, which is what this laser cutting company recommends for thick material. When the company making the equipment recommends something else, they have a reason. There was some mention of cost of laser vs routers. Lasers are inefficient. It takes a lot of power to generate a laser beam. Aluminum is very reflective and most of that inefficiently converted power will be reflected away. Good for steel, titanium almost anything but aluminum.

I don't agree with the poster who was concerned with contamination from the abrasive used. Water jets cut cleanly and can cut almost anything. For my money, water jet is better. Plasma, I have only seen with steel, so I will not comment.

Someone mentioned cutting aluminum with a circular saw using a standard carbide tipped wood blade. There are expensive industrial metal cutting blades and there are cheap off brand wood blades. The expensive blade will outlast the cheap one, but the cheap one will cost 1/10 as much, last half as long and cut just as well. I have cut some of the strongest aluminum alloys around, up to 50mm thick on a 10" table saw with an ordinary carbide tipped wood blade. I have cut 37 mm thick alloy 7068 with a yield strength just over 700 MPa on a portable contractors saw. A steel bar that strong would take the teeth right off that blade. Curved cuts are a problem for a circular saw though.

MIG is probably the best choice for welding. There are some more expensive, exotic ways to weld, if you have more money than most governments.

Alloys, look into ASTM B928 and be careful of the temper you order. There is marine grade and there is the lot that failed the corrosion test and was sold with a different temper designation. I doubt that any mill would scrap 50,000 lb if they could sell it under ASTM B209.

 

RSD,

Why were you considering o/b's?
Cost?

If the Yanmar/jet works economically,
would you consider longer and skinnier
hulls to increase the cruising speed?
No, 12m is a government convenience limit.
Design the pontoons far apart and reduce their individual widths.
This will give you better economy and higher cruising speed.
And improve seagoing capacity with higher freeboard.
But you gotta keep it light weight.
No air compressor on board, right?
One helm ( a flying bridge ) would reduce cost and weight vs two.

Water cutting your aluminum would be preferred.
I'm confident Mr Poleson will know what to do.
I like the idea of using his 12m x 5.5m cat hull.
Just be sure it doesn't surpass the 12m government measuring test.

Would you recess the lift or transom mount it?
Less pitch / heaving recessed, less "prop" wash from the jets too.

How many dive boats do you have now?

Do you operate out of the Sea Dream Hotel or at least in that bay?

 

Hi RSD,

I hope you're moving forward with your project.
I may have some international clients for you.

BB