This blog is intended to describe our approach to acquiring a stern arch for Kwanza.
As we thought about long distant cruising it became clear that additional electrical power to charge the batteries could economically come from solar and wind power.
So we decided to invest in an arch, added to the stern of the boat. A common sight on many long distant cruising yachts.
Advantages of installing an arch are:
- System for suspending the dinghy out of the water (davits)
- Place to mount antennae of various types. For example GPS, VHF, Active radar detector
- Mounting stand for solar panels
- stand for a wind generator
CHOICE OF MODELS
There were 4 options considered.
OPTION 1
Beneteau basic model offered to customers. It was one design that fitted three different models of Oceanis (41, 45 and 48). It was simple in detail and only seemed to provide dinghy support function (davits). The height was not adequate to allow easy access to and from the swim platform. However it did allow the conventional Beneteau Bimini to be used..JPG) |
| This model was available for sale |
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| Attachment on the transom |
.JPG) |
| Low headroom ! |
Reputedly made in Poland.
OPTION 2
Arches constructed in America (USA)There are several well know manufacturers of arches for specific Beneteau yachts.
For example: www.katomarine.com
Cost of their basic arch unit:
Main bows constructed of 1 ½” x 14ga T316 s/s tube
Truss constructed of 1” x 16ga T316 s/s tube with 5/8” round bar and 11ga corner plates
(2) 1/4” s/s loops for retaining tackle ‘at rest’
(2) 3/8” s/s welded cleats
(4) 3/8” s/s bases with polished bolts
(4) 1/4” aluminum matching backing plates
(4) Wiring messengers
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| THIS MODEL SEEN ON A OC48 IN FETHYE |
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| The dinghy is slung very high and precariously |
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| The support included the existing pushpits |
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| Support of this arch does not include pushpits.. |
Other manufacturers are:
A/ Klacko marine
http://www.klackomarine.com
B/ Wells
Weslee Wells
Wells Marine Stainless Fabrication, Inc.
The problem we had with arches made in USA was obviously the very high cost of transportation and the fact that you would have to buy a ready made unit and take the risk of whether it would fit without adjustments.
Also the price of the KATO arch was high and all additional equipment also cost a lot.
A complete arch would cost 10,000 USD.
OPTION 3
This below was an arch installed on a Beneteau Oc38 which was displayed by Beneteau themselves. When we wrote to them to ask for the design or manufacturers detail, they completely ignored our correspondence. |
OPTION 4
Purpose made arch, based on various models installed on a variety of cruising yachts.We contracted PHOENIX316 to build the arch for us.
While passing through the Plymouth harbour in September 2014 we made an appointment to see the MD of Phoenix316 to ask him on board our yacht and to give us a quotation for an arch.
He came up with a range of ideas for the kind of arch we could install together with options for davits, wind generator, panels etc.
We liked the MD's offer but we couldn't organise our trip in order to stay in Plymouth for the job to be done. However we kept in contact with Phoenix316, and after we picked up our yacht in March 2015, we cruised back along the coast to Plymouth to have the job done. The time required by Phoenix316 to manufacture the arch was quoted at 3 weeks so we planned 4 weeks to be on the safe side and allow us time to also install solar panels and wind generator etc.
So the work began on Monday the 23rd March 2015. The Phoenix316 foreman came to the boat at 11.00 and measured up for the arch. The plan was discussed and he went away with the intention to build it in 4 days, before he went on holiday.
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| THIS WAS THE DESIGN |
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| THE STRUCTURE TAKES SHAPE IN THE WORKSHOP |
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| NOTES AS WE WENT ALONG |
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| THE PUSHPINS WERE REMOVED |
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| The area under the attachments was already reinforced |
FINAL PRODUCT
When the arch was completed there were a few problems encountered while installing it on the boat:
A/ The line-up of the holes with the deck was just off. Some elongating of holes was required.
B/ The height of the whole structure was not as I wanted (it was too short). There had been a mistake with the measurement performed at the outset. I had erected the bimini on the boat during the measurement process so the height was made clear. (the arch should have been higher than the bimini by about 10cm..)
C/ The inner pushpit stanchions on each side had to be cut shorter for the structure's outer feet to fit flush to the deck. This caused slight problem with guard wire alignment later, and of course cost me a lot more for the man-hours of installation since the arch had to be removed and carried back to the shop which was situated about 300 meters from the marina. This problem surprised me since the shop foreman had used a "dolly" method of duplicating the yacht stern in the shop. I had removed the pushpits and given them to the foreman who had then used them to build the arch in the shop.
When the arch was being built I visited the workshop every day and I had noted that various inconveniences played a part in reducing the quality of the product.
These were:
1/ Work overload of the manufacturer meant the job was done in a hurry. The foreman who actually constructed the arch was juggling his holidays around the time of the build.
2/ I had given them clear limitations and dozens of photos of the arch I wanted to be copied. Due to their rush to build they didn't look at these pictures adequately.
CONCLUSION
The arch is fine.. HOWEVER not perfect.... and this is a shame since I had spent a huge amount of time researching and explaining the requirements to the builder.
My overall dilemma was : Should I trust the manufacturer to provide a perfect arch because they had built so many arches for yachts before.?.. OR should I provide an engineering drawings for the arch I wanted and monitor the build ?
Never mind. The job is done and the arch is very sturdy.!
SOME PHOTOS:
