Stern arch thoughts

[Pavalijo]

I went through this when fitting out for my circumnavigation . The usual arches were heavy and very expensive . My sailmaker solved the problem for me . I was fitting a bimini and was concerned that it might not be strong enough to leave up in heavy weather . He suggested that it would be and that we add an extra arch to carry arials and the solar panel . This after 36000nm has been well tested, works, has stood up to all conditions encountered during Atlantic and Pacific crossings . Inexpensive and it also looks good .

Any chance of photos? I have in mind combining arch and Bimini. Have seen solar panels zipped onto a Bimini and wondered how that might affect performance, which is apparently better at lower temperatures. Did you have airflow beneath the panels?

 

[duncan99210]

Solar: we have about 200 watts of panels fixed to the decks and bimini but because of shadowing they never produce enough to keep pace with demand. We're looking at an arch next summer; locally made it will come in at about €1000.

Wind/hyrogeneration: we have an Aquair 100 which produces 4 - 5 amps in a force 4 and above but comes into its own when sailing. It produces about 1 amp per knot of speed. The conversion from water to wind takes about twenty minutes and because it's held up by the backstay and topping lift there's no noise transmitted to the boat. That said, I'm looking at a D400 if money is available as it starting windspeed is much the lowest I've seen.

We're based in Greece at the moment so there's lots of sun but no dependable wind..."

 

[Chris_Robb]

Don't even think about getting an arch and solar if you haven't first got a Sterling! If you have a 115A alternator, then you can easily install up to about 400Ah of batteries and charge them properly with very little engine running. 400Ah of battery will keep you going for 2-3 days with fridge, TV lights etc.

Also, have you got a decent battery monitor (e.g. NASA BM-1)? Without a battery monitor you won't be optimising your battery usage anyway.

My advice, in this order:
1. Fit battery monitor so you know what you are using and charging.
2. Fit Sterling
3. Increase battery capacity to about 400Ah

You will probably find you don't need solar or wind with the program you appear to have. If you really do need an additional source, look at a wind-genny on a pole and deck mounted flexible panels.

Don't get a stern arch until you REALLY need it. They cost masses of money, add loads of weight and windage, are ugly and unnecessary on a coastal boat. Having said that, I really like them on certain types of boats and for certain programs.

Ric, absolutely agree with the above. Without a monitor you have no idea of what is happening.

BUT - a 115 amh alternator will take some driving. I have the same from Prestolite, plus a sterling charge regulator. I used to charge my batteries at 14.8V, and if the batteries were discharghed it would charge at 100A. Initially the belt set up was the standard VP2003T - a 9mm V belt. The belt slipped so much that the boat filled with smoke! However, Adverc (the supplier) had fitted a 13mm pulley to the alternator, and said I should buy a 13mm V belt. I did, and I have never had any slippage since.

I now run my sterling at 14.4 as I have sealed LA batteries, and I think the 14.8V contributed to the early demise (1 year) of the Numax set - one of which had to be thrown overboard as it was red hot.

It is interesting to see the different rate in charge of 14.8 to 14.4V. The max charge I get now is 75A. It just show you that people charging at below 14V will be getting a pathetic charge rate.

Edit: A point to note is that if you uprate your alternator significantly, you need to uprate the wiring - ie double up the cables. When I did this on my set up, I got an increase from 80a to 100a charge rate - that must have been a lot of energy to get lost in the wiring.

 

[Chris_Robb]

What do you mean please ??? Hydrogenation is a process related saturated fats in food !!

Now known a di-glycerides by the industry to mislead us......

 

[wilkinsonsails]

We used two 1" tube arcs (got them welded apart at the right angles,)which are fitted to the rail with sprayhood fittings and through bolted thru the tube legs.
It was a very low cost alternative and removable too.
It supports our panel and aerials.
Cindy

 

[Aja]

Gasdave

Have you talked to Donald Cameron at Argyle Metal Services (Scotland) Ltd yet? Tel: 01389 764140

Unit 32, Lime Rd, Broadmeadow Industrial Estate, Dumbarton, Dunbartonshire, G82 2RP

He really does do some fantastic work and knows boats.

Regards

Donald

 

[Gordonmc]

I used just the frame of a taff-rail bimini for a stern arch which holds two rigid panels. They are attached with bought frame clips and so far the arrangement has survived for three seasons or so without problems.
One refinement which I will get round to is to have the junctions, which are normal bimini fittings, welded up to provide some more rigidity. Most of them are galled in any case and the grub-screws are in for good

 

[prv]

Hadn't been reading this thread as I'm not interested in arches

But for coastal cruising I'd second the advice to optimise the engine generation before hanging wind and solar off the outside.

Ariam has the standard 115amp alternator on a Volvo D1-30 - possibly this is what you also have? I replaced the existing pair of knackered Halfords leisure batteries with two 210Ah AGMs (plus a 28Ah for engine starting) and also fitted a Merlin "Alternator Management System" - this is the same idea as the Sterling units suggested already. I also have a Smartgauge monitor to show the state of charge.

We don't have power at our home berth so most of the time the engine is the sole charging source. I do plug in occasionally in marinas, but mostly just to keep the water hot with the immersion. If there's the slightest difficulty (they want extra money, or to use a meter, or we're rafted out, or the socket is a way down the pontoon, or even just that I've opened a beer and can't be arsed) then I don't plug in, the batteries never need it.

I don't motor excessively, but the short runs in and out of harbour keep things topped up, and the occasional windless day or passage deadline make double sure. The battery is above 90% charged much of the time, and almost always above 80%.

My parents left the boat in Falmouth marina with the fridge running for over a week this summer - they were plugged into the mains and wanted to leave some food on board for their next visit. Unfortunately the battery charger wasn't actually turned on, so the fridge was running on the batteries with no charging. When they returned they found the fridge nice and cold and the battery at 40% - they motored up the Carrick Roads to have lunch in the Truro river, and reported that the battery was now back to 100%.

Large AGMs that can accept a high rate of charge, plus an alternator booster that produces it, are the way to go unless you really won't be running the engine at all for days at a time.

Pete

 

[GHA]

Large AGMs that can accept a high rate of charge, plus an alternator booster that produces it, are the way to go unless you really won't be running the engine at all for days at a time.

Maybe, unless your alternator is a newer one..

http://www.smartgauge.co.uk/controllers.html

Mine will get to almost 14.5v at the batteries.

 

[prv]

Maybe, unless your alternator is a newer one..

http://www.smartgauge.co.uk/controllers.html

Mine will get to almost 14.5v at the batteries.

Sadly I don't have all the figures in my head any more. But Ariam's alternator is only a few years old, having been re-engined shortly before we bought her, yet the voltage is not all that high. The booster raises it significantly - I could be wrong, but 15.2v rings a bell. This would be overcharging for a bog-standard leisure battery, but my AGMs lap it up. Of course this is a controlled multi-stage charge cycle, it reduces to a float voltage when the batteries are full.

Kindred Spirit had ordinary leisure batteries, and I followed Gibbo's advice on that page and just used the standard alternator regulator and new high quality wiring with a minimum of joints. You have to consider the system as a whole.

On both boats I used the Smartgauge and Smartbank relay system, so all mention of diodes is misplaced, and Ariam was and is battery sensed (both the standard regulator and the booster had a sense wire).

Pete

 

[chrisb]

I'll look for a photo . Mine was made for me by Denzil at Stephen Ratsey Sails, Neyland , Pembrokeshire . It is a standard bimini which stays up all of the time .There is an additional hoop at the stern with the panels slung between it and the the rear hoop of the bimini leaving space for arials . It is robust and works well . Very light . It would not be suitable for using as a davit but has stood up to all the weather that has been thrown at it for 5 years . If you look on my wife's blog "sailaway' or 'esprit de la mer' at sailblogs there should be photo's in the galleries .
The hoops are attached to the deck as per a bimini which I think is probably better and stronger than attaching to the stern rail as the deck fittings allow some flexibility

 

[dansaskip]

Any chance of photos? I have in mind combining arch and Bimini. Have seen solar panels zipped onto a Bimini and wondered how that might affect performance, which is apparently better at lower temperatures. Did you have airflow beneath the panels?

A picture of mine, and some thoughts which might help. At first had just the arch and solar panel which I fitted in Wales, the arch is quite high as I wanted to be able to stand upright on the cockpit seat under it and climb in and out over the pushpit without obstruction. Also to not obstruct airflow to wind vane of self steering. The bimini I had made over in the Caribbean, partly because of the silly prices I was quoted in the UK but also because they are so common out there there is no problem getting one made and fitted. The bimini uses the arch plus area bar and a folding front hoop. It stays up just about all the time, sailing or at anchor button be quickly and easily folded out of the way, or even taken off. It is also adjustable to a degree in height. Size on my boat is limited by mainsheet arrangement and height of boom but I can stand upright under it. Hope this helps you.