Seaquest 46 Performance Cruising Catamaran

[Joli]

Full time cruisers motor more often then we think we are going to. You might consider having engine beds included in your build just in case further down the road you have a change of heart about adding diesel auxiliaries.

Good luck with the new boat and enjoy!

[toolbar]

> 5 knots is all the SQ46 needs to move at 5 knots.

Yeah, but are those 5 knots of movement going into the direction you want to go? Murphy's law holds that those 5 knots of wind alway come from 180 degrees TWA. And in that case your VMG will probably drop to embarrasingly small numbers.

Paul

[Ratel]

All good points. I guess it al depends on the individual. There is always the option of using the Oceanvolt hybrid system with a DC generator (Hull #2 will be built with this)

I might consider a small suitcase generator as a "range extender".

[Tupaia]

Originally Posted by Joli

Full time cruisers motor more often then we think we are going to. You might consider having engine beds included in your build just in case further down the road you have a change of heart about adding diesel auxiliaries.

Good luck with the new boat and enjoy!

I have to disagree unless your boat really can't sail in light airs. In 22 years 17 full time live aboard I am showing just under 2000 engine hrs.


Engine beds just in case is unnecessary weight and cost. Cutting a hole and retro fitting a sail-drive is no big deal.



My cat is a similar size and weight to what is being discussed here.


Is the spec'd displacement WL displacement and what is the anticipated payload?



I have tankage for 280ltrs giving me a range of between 500 and 700Nm. In 20+ years the longest time I have had to motor on a passage is 23 hours, complete calm ahead of a storm front. I am quite happy to stop and enjoy the ocean if there is absolutely no wind at all, which is very rare. So IMO for distance cruising you realistically need an immediately available range of about 140-150Nm. The additional fuel, in reserve, is only there for areas where fuel may not be available. On a solar charged boat obtaining fuel is not an issue provided the immediately available range is sufficient, but for a hybrid (generator) you still need fuel so the extra weight of the generator, the fuel and reserve fuel, needs to be factored in. This either increases the overall weight or restricts the load carrying ability. Cats don't perform well if overloaded.

[Ratel]

"Is the spec'd displacement WL displacement and what is the anticipated payload?"

Yes, the spec'd displacement is WL of 46'
The anticipated payload is 2 tons.

[Joli]

Originally Posted by Tupaia

I have to disagree unless your boat really can't sail in light airs. In 22 years 17 full time live aboard I am showing just under 2000 engine hrs.


Engine beds just in case is unnecessary weight and cost. Cutting a hole and retro fitting a sail-drive is no big deal.



My cat is a similar size and weight to what is being discussed here.


Is the spec'd displacement WL displacement and what is the anticipated payload?



I have tankage for 280ltrs giving me a range of between 500 and 700Nm. In 20+ years the longest time I have had to motor on a passage is 23 hours, complete calm ahead of a storm front. I am quite happy to stop and enjoy the ocean if there is absolutely no wind at all, which is very rare. So IMO for distance cruising you realistically need an immediately available range of about 140-150Nm. The additional fuel, in reserve, is only there for areas where fuel may not be available. On a solar charged boat obtaining fuel is not an issue provided the immediately available range is sufficient, but for a hybrid (generator) you still need fuel so the extra weight of the generator, the fuel and reserve fuel, needs to be factored in. This either increases the overall weight or restricts the load carrying ability. Cats don't perform well if overloaded.

Will batteries provide a 150 nm range?

[Ratel]

"Will batteries provide a 150 nm range?"

The Oceanvolt 43kWh battery bank will give the SQ46 80-100 nm range motoring at 3-4 kts(realistic sea conditions) In flat water the estimated range at 3 kts is 140 nm.

Install a Fischer Panda 5000i Neo (weighs 77kg +100 or 150 liter diesel) as a range extender?

There is also 3000w solar panels on the roof.

[donradcliffe]

I compared the advertised polars to a gunboat 66. The Sequest claims it is faster in light airs. Good luck with the actual performance.

[Ratel]

Originally Posted by donradcliffe

I compared the advertised polars to a gunboat 66. The Sequest claims it is faster in light airs. Good luck with the actual performance.

Thanks! Rest assured, I will report back on the actual performance after launch

[donradcliffe]

Originally Posted by Ratel

The hull, deck and roof is built from E-glass and Vinylester. Carbon Fiber is used extensively in high load areas. All bulk heads are laminated to the hull.

The curved foils are 100% carbon fiber with a foam core.

Looking at the time lapse build, it seems like they assembled the bulkheads, put longitudinal stringers in, then bent some think skins over the stringers, then glassed the outside? Are the skins plywood?

Will your boat have a propane system for cooking? It seemed to me that part of the reason for the failure of Jimmy Cornell's regenerative electrical system was his insistence on electric cookers. I think that Ocean Volt also overcomplicated the variable pitch prop control system. The regenerative concept still may work, but you are going to lose 25-50% of your polar performance.

[Ratel]

"Looking at the time lapse build, it seems like they assembled the bulkheads, put longitudinal stringers in, then bent some think skins over the stringers, then glassed the outside? Are the skins plywood?"

The timelapse on the website you are referring to is the mold being built. The actual hull is vacuum infused inside that mold. Every thing you see on that timelapse was thrown away after the completion of the mold.

The hull is made of E-glass, foam core, Vinylester and carbon fibre.

[Ratel]

"Will your boat have a propane system for cooking?"

No propane on our boat, induction cooking and a combination microwave/convection oven.

Jimmy Cornell's "failure" as you call it was due to many reasons. Oceanvolt has made changes (software) since then to the regen. The penalty for using the regen whilst sailing is marginal. Maybe 1knot penalty when sailing at 10 knots.

Again, we will document all these performance numbers and post them here. Our SQ46 is launching in August/September

[donradcliffe]

Originally Posted by Ratel

"Looking at the time lapse build, it seems like they assembled the bulkheads, put longitudinal stringers in, then bent some think skins over the stringers, then glassed the outside? Are the skins plywood?"

The timelapse on the website you are referring to is the mold being built. The actual hull is vacuum infused inside that mold. Every thing you see on that timelapse was thrown away after the completion of the mold.

The hull is made of E-glass, foam core, Vinylester and carbon fibre.

That makes more sense than the video. I also noted that the rear step design seems to vary in the various views, and didn't look like the mold. I'm sure all these details will be finalized in the first build.

[donradcliffe]

Originally Posted by Ratel

"Will your boat have a propane system for cooking?"

No propane on our boat, induction cooking and a combination microwave/convection oven.

Jimmy Cornell's "failure" as you call it was due to many reasons. Oceanvolt has made changes (software) since then to the regen. The penalty for using the regen whilst sailing is marginal. Maybe 1knot penalty when sailing at 10 knots.

Again, we will document all these performance numbers and post them here. Our SQ46 is launching in August/September

I agree that some regen should be feasible. The software can reduce the performance drag at the expense of the regeneration power. My own experience with a towed generator on a 46ft mono was that with 100 watt output the performance penalty was acceptable when reaching or running in higher winds, but even 50 watts was too much in lower winds, especially when beating.

[Ratel]

https://www.google.com/amp/s/oceanvo...ric-shock/amp/