Using an arch as a davits - Sanity Check

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sidthekid
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Using an arch as a davits - Sanity Check

Interesting recent disussion about using stern plate to mount outboard, and I'll throw in another confirguration. Would appreciate any and all feedback on feasibility of this approach.

Boat (2002 C36 MKII) has an Atlantic Tower arch with 2 solar panels on top. (see photo).
I'd like to attach the Garhouser lifting block and tackle system to the arch.
Looking at a dinghy weighing 115 lbs and 5 HP Honda weighing 60 pounds (total weight 175-200 lbs)
Thinking I might be able to use the Port side Garhouser tackle to lift outboard to stern plate when required.

Questions:

Can an arch subsitute for a davits without damaging the boat or creating a unwanted condition (sailing performance, safety?)
Can I do a local sail in fair weather with dinghy and outboard on dinghy transom hanging off the arch?
Can I leave the dinghy with outboard on the dinghy transom hanging off the arch while in the slip?
Will the Garhouser block and tackle be an adequate outboard lift?

Are the Torqeedo outboards reliable? I've read about computer faults which make the standard OB a reliable choice.

Bill & Barb
s/v Northern Lights
2002 Catalina 36 MKII #2086
Rock Hall, MD
Northern Chesapeake

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Wow, that is one robust arch. Have any idea what that weighs? Is it made from 1 1/2" stainless tube? A finger on the lens is blocking what the construction at the top looks like.
Have you ever grabbed it and hung from it to see how it supports your weight? Maybe do some swinging to see how it flexes.
 It looks like it would place the dinghy center of gracity much higher than if it were supported  by davits- meaning the rocking motion from waves would impart a lot more side to side force.
With a small outboard, our dinghy weighs in about 160 lbs. The davits are 1 1/4" tubes (I think). The dinghy is a little higher than the stern rail. I wouldnt want to add much more weight to our configuration, and it's a relatively low height compared to your arch.

 

Paul & Wendy Keyser
"First Light"
Rye NH
2005 C36 MKII #2257
Wing, M35B

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sidthekid
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Thanks for the perspective Paul.

Yes, that would be my finger... I uploaded another attachment of the full view. Not sure of the weight but is it 1 1/2 inch Aluminum made by Atlantic Towers. It was purchased by the PO. Not done any swinging off it yet!

Here is a link to an arch with panels and a dink/motor, albeit the arch is mounted differently.
https://www.atlantictowers.com/images/content_photos/Johan.jpg

Bill & Barb
s/v Northern Lights
2002 Catalina 36 MKII #2086
Rock Hall, MD
Northern Chesapeake

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Can't offer a comment on the main topic (i.e., whether the arch would be strong enough for what you are thinking), although I agree with Peter that it sure looks robust (assume it has backing plates for the attachment points).

As to your questions about the Torqeedo: We had some problems with it when we bought ours 3 years ago (sometimes it just wouldn't respond unless I cycled it on and off a few times); Torqeedo promptly sent us another and its been fine.  Its certainly a pricy replacement for a gas outboard, but the ease of use (my wife was never able to manage the pull-start on our old Mercury 5HP 2stroke), the light weight (I can lift it into the boat with one hand and stash it in the lazarette), the joy of not having the take apart and clean the carburator 5 times a season once it got gunked up from ethanol additives (usually at the wort times), and not having to carry gasoline on the boat anymore, have certainly proved to be major plusses.  If it lasts 5 years I'll be happy (I bought an extended warranty).  Obviously, not for everyone, depending on what kind of cruising you do.   Keeping it charged has not been a problem; I made up a plug so I can divert one of our solar panels' (145W) output directly to the outboard's battery, which charges more quickly at higher voltages (in this instance, 18V).  If you try recharging from 12V, it takes forever; if you charge from dock power its relatively quick.    There's a blog with about over 150 comments spread over 7 years pertaining to the Torqeedo here: www.panbo.com/the-travel-1003
 

Matthew Chachère
s/v ¡Que Chévere!
(Formerly 1985 C36 MKI #466 tall rig fin keel M25)
2006 Catalina Morgan 440 #30.
Homeported in eastern Long Island, NY

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sidthekid
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Matthew, thank you very much for your comments about the Torqeedo. I really do like the "ease of use" features, as long as the reliability is there... Arch does have back plates installed and has seemed very secure for last 3 seasons. When it comes to weight hanging off the stern, "less is probalbly better", therefore my interest in Torqeedo and ultra light dink.

Bill & Barb
s/v Northern Lights
2002 Catalina 36 MKII #2086
Rock Hall, MD
Northern Chesapeake

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Bill/Barb
OK. I see from the other picture somebody is using the arch for davits- and they are keeping the dink low- at stern rail level. That's a smart way to do it- keeps the windage low (the dinghy is level and not at an angle to the wind acting like a sail), and reduces the stress created from the side to side motion- assuming the dinghy is nicely tied off onto the stern rails. I would see if the arch manufacturer has a weight limit on the structure. If they do promote it for davit use, they would likely sell the associated accessories- cam cleates with fairleads, cleats and purchase blocks. If your dink/motor is in the 160 lb range, you would need a 6:1 purchase to easily lift it (ie each pair of blocks have three pullies). 

Small 4 stroke engines have small diameter carbureter jets (to minimize pollution/maximize fuel economy). They are guarenteed to clog up with ethanol gas and make for impossible starting. Out of frustration, our PO gave us a new 3.5 hp Tohatso  when we bought our C36 from him. It wouldn't run with standard gasoline. I switched to aviation gas - it contains no ethanol and the engine starts with the first pull. It's available at most small airports. It's expensive, but worth every penny. You can also buy small ethanol free gas from power equipments stores like Tractor Supply (and pay more than aviation fuel).

Paul & Wendy Keyser
"First Light"
Rye NH
2005 C36 MKII #2257
Wing, M35B

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sidthekid
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Paul, thanks for your opinion on the arch setup in the attached photo. I have seen a few boats out on the bay with dinghys off an arch, but not many. The ethonal free fuel does sound like a good way to go for the OB. I already got some on head for the yard tools....

Bill & Barb
s/v Northern Lights
2002 Catalina 36 MKII #2086
Rock Hall, MD
Northern Chesapeake

pierview
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If you hang the dinghy from the arch, where will you put your stern light? Can you move it to the top of the arch?

Chuck Parker
HelenRita 2072 Mk II
2002 Tall Rig - Winged Keel
Atlantic Highlands, NJ

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sidthekid
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Chuck, good question, thanks for bringing it up. There is wiring from the panels down the starboard arch tubing, maybe I can use that route to raise the location of the stern light.

Bill & Barb
s/v Northern Lights
2002 Catalina 36 MKII #2086
Rock Hall, MD
Northern Chesapeake

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