Beneteau 38

[Fluer de Mer]

Matt, did the auditory alarm you experinced include a readout on the saloon pannel like the attached photo? Has anyone else seen this and/or know what it is? I cant find a symbol key in any manuals. Pls advise. FdM

[hellosailor]

Fleur-
The icon is a battery, the one below it looks like an "alert" or "alarm off" button.
12.6V would indicate you are running on battery, not engine, power and the "ENGINE" would emphasize that the engine, or engine power source, has failed.


They didn't teach us Iconese in high school, but I've been studying it on my own.(G)


Computer memory has been SO CHEAP for SO LONG you wonder why some cheap SOBs haven't bothered to make clearer error messages.

[mstrebe]

FdM, thanks for the post on the assym. I'd attempted to order an assym on a Selden furler, but the loft dropped the ball so I cancelled the order, and then found during a race that people with Assyms on similar B41s were having furler problems while those with a simpler sock were dousing them just fine.

Since we've put the boat in Charter, the chartering company does not want us to keep an assym on board because they're easy to damage and they don't want to be responsible for it, so I'd have to take it on and off with me when we sail. How big/heavy is it in the bag?

I find I'm consistently able to do about 50% of true windspeed downwind on just the main and jib wing-on-wing using my boathook as a whisker-pole. So in 10 knots of wind I can do five dead downwind. What would you estimate you're doing with the assym?

Last week coming home the true wind moved to a broad reach at 8 knots, and I dropped to 4 knots, so the 50% number is pretty consistent whenever the wind is abaft a beam reach. When close hauled, it's easy to get to 70% and possible to get to 80% with good attentive trimming, and I'd like to be in that range downwind with the Assym.

In another thread Polux advocated the assym for this boat, and I'd like to get a feel for what your real-world efficiency is.

How are you managing the tackline? Shackled to the pad-eye on the bow, or using a block off the bow roller and a tackline back to the clutches?

Thanks,

Matt

[mstrebe]

Originally Posted by Fluer de Mer

Matt, did the auditory alarm you experinced include a readout on the saloon pannel like the attached photo? Has anyone else seen this and/or know what it is? I cant find a symbol key in any manuals. Pls advise. FdM

It did not. The main panel showed nothing unusual. The battery light on the engine panel at the helm is the only place the alarm sounded.

[mstrebe]

Also, what's the lowest windspeed you can flew the assym at? Can you send a photo of those spinnaker sheet-blocks? I have the spinnaker jib and hardware stock but the boat did not come with detachable sheet-blocks, and I'd like to make sure I get the right thing. Do these blocks have a clutch or cam-cleat on them?

[homerobarros]

Originally Posted by Fluer de Mer

Matt, did the auditory alarm you experinced include a readout on the saloon pannel like the attached photo? Has anyone else seen this and/or know what it is? I cant find a symbol key in any manuals. Pls advise. FdM

FDM,I had the same alarm and engine failure error, although the engine was off. I shut everything off, including the main switch in the aft cabin and the alarm was off and the error message disappeared...
Have no clue what happened but it was gone and never appeared again.

[homerobarros]

Originally Posted by mstrebe

We just got back from our trip last night, and they're troubleshooting now. I don't think we're every going to figure out the why of it. Those mitsubishi alternators are quite bulletproof, and they have shunts to prevent blowing if the motor runs while the system is shut off. It's likely just a random failure due to a marginal diode.




Well, it won't help if you don't know how to use it. Electronics is pretty easy stuff. There are a few pretty good books specifically made to teach the requisite knowledge to boat owners you might want to look into.

Here's a simple analogy using pressurized water pipes:

voltage: Water pressure (speed of flow)
Amperage: Pipe diameter
Wattage: Total water moved per second (pressure * diameter)

Direct Current (DC): Water in the system moves from source (positive) to sink (negative) to transfer energy. DC is used because it's simple and what batteries provide naturally. DC suffers from high resistance (turbulence that slows the flow) due to the buildup of magnetic fields when electricity flows through a wire.

Alternating Current (AC): Water in the system moves back and forth in the pipes (like a plunger does to water in a pipe) to transfer energy. AC is used because it doesn't build up magnetic fields (like turbulence in the pipes) that resist flow as much as DC which cause voltage drops (lower pressure due to turbulence) over distance. AC is also the natural product of a simple rotating magnet over a wire (called an Alternator)

Wire: A pipe
Diode: A one-way valve
Resistor: A flow limiter
Capacitor: A small water tank inline with a pipe.
Battery: A large water tank
Generator: A pump
Alternator: A plunger
Motor: A waterwheel
Solar Panel: A rain collector
Transformer: A pipe size coupler (i.e. large pipe to small, or vice versa, which increases or lowers pressure and the opposite for diameter)

On a boat, the engine drives the alternator with a belt, which produces AC. The AC is put through a simple system of four diodes called a rectifier that converts the AC into pulses of DC, which are smoothed out using a capacitor into DC power that can charge a battery.

Converting AC to DC is simple and can be done with very inexpensive parts, but this wasn't the case until the invention of the diode in the 50's. Diodes are the least-complicated semiconductor.

Converting DC to AC is extremely difficult and requires electronics that construct an AC wave synthetically called an inverter. Inverters are expensive and prone to failure. Before inverters, conversion of DC to AC was done by powering a DC motor to drive an alternator, but that is quite inefficient.

A meter lets you test for the presence of electricity (voltage or amperage) at any point in the system, which helps to isolate what part is broken.

You do have to know how the system is wired and what the major components do. The wiring is the manual, and I used it to trace out what could be wrong.

Matt, thank you very much for the extensive explanation. Will need to read several times to really sink in.
Cheers.

[Silver Shadow]

I would like to know (as well) the attachment of the tackline in "stock" configuration?

The pictures in brochures all have double anchor roller on them (which includes a bobstay) - how does spinnaker tack attach in single anchor roller configuration? - is some sort of bobstay (or similar support) needed?

Originally Posted by mstrebe

How are you managing the tackline? Shackled to the pad-eye on the bow, or using a block off the bow roller and a tackline back to the clutches?

Thanks,

Matt

[Garrettw]

Originally Posted by Silver Shadow

I would like to know (as well) the attachment of the tackline in "stock" configuration?

The pictures in brochures all have double anchor roller on them (which includes a bobstay) - how does spinnaker tack attach in single anchor roller configuration? - is some sort of bobstay (or similar support) needed?

I suspect that Beneteau uses the same anchor roller part as Jeanneau (they share a lot of the same OEM items). In the case of Jeanneau, and likely Beneteau, the assym tack point is an advertised feature for the double roller part. You don't get a tack point with the single roller setup except in cases where the boat design includes a separate bowsprit. If that was the configuration you had, you would need something done aftermarket.

[Fluer de Mer]

I will post a photo of the spin blocks later as my iphone camera broke. But, attached is an older photo I took of the tack connection point on double bow roller. Regarding speed…we measured the delta over the stock main/genoa and were consistently getting 75-85% (of true wind speed) with winds under 10 knots, but once the winds got to above 10 knots, the delta significantly fell off such that the sail really doesn’t make sense using (we might not have figured the trim thing out yet at these higher wind speeds). Regardless, we found that how the main is trimmed (or more accurately eased) and vang is tensioned (or more accurately eased) really impacts the efficiency of the sail. Next weekend we will take it out and experiment again and report numbers and post photos.

[Fluer de Mer]

BTW, what is the hull speed of the O38?

[homerobarros]

Originally Posted by Fluer de Mer

I will post a photo of the spin blocks later as my iphone camera broke. But, attached is an older photo I took of the tack connection point on double bow roller. Regarding speed…we measured the delta over the stock main/genoa and were consistently getting 75-85% (of true wind speed) with winds under 10 knots, but once the winds got to above 10 knots, the delta significantly fell off such that the sail really doesn’t make sense using (we might not have figured the trim thing out yet at these higher wind speeds). Regardless, we found that how the main is trimmed (or more accurately eased) and vang is tensioned (or more accurately eased) really impacts the efficiency of the sail. Next weekend we will take it out and experiment again and report numbers and post photos.

FDM, what's that for an anchor? I have a Delta, but heard the Spade is better. Your thoughts....
Cheers

[Fluer de Mer]

FYI, I had a 1/2" thick flat cutting board made that fits on top of stove that creates more counter space when not using the burners. Cost was $20 and fits within stove walls so doesn't rattle or slide out when underway.

[mstrebe]

Originally Posted by Fluer de Mer

BTW, what is the hull speed of the O38?

It's a bit subjective. Classically, hull speed was defined as 1.34*root(LWL), which for an Oceanis 38 with an LWL of 35'2" yields 7.94, or 8 knots.

However, the 1.34 number is a general hull efficiency that the Royal Navy arrived at from empirical testing over a century ago, and as such it's something of an "average" efficiency factor based on classic shaped hulls.

In my experience, the O38 easily gets to 8.5 knots before it meets significant bow wave resistance, which is the element that truly determines hull speed, and so I think the correct hull efficiency factor for this boat is 1.43. That's well within the standard "range" of 1.2 (bathtubs) to 1.5 (serious racers).

I've gotten my boat up to 9.5 knots in high winds, and she's done up to 10.3. But those are very inefficient speeds (making only 25% of wind into speed), and indicate that the boat planes ahead of its bow-wave, which many hulls simply cannot do. However, these semi-planing speeds don't count as hull speed which only includes displacement speed. The inefficiency is also expressed as extreme heeling and in my experience extreme leeway, which aren't all that useful except in racing.

I say the hull speed is 8.5 knots based on my experience. It's certainly 8+ knots.

[mstrebe]

Originally Posted by Fluer de Mer

FYI, I had a 1/2" thick flat cutting board made that fits on top of stove that creates more counter space when not using the burners. Cost was $20 and fits within stove walls so doesn't rattle or slide out when underway.

Great idea--copying. I see you keep your paper towels in the same place we do.