Pushpit arch

tsmyth

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I have a Boomaroo 22.

I was wondering if it might be possible, or advisable, to fit an "arch" over the pushpit.

My idea was to make this of stainless steel tubing attached to the vertical supports of the existing pushpit. Perhaps it could be curved slightly to result in the horizontal part of the arch being say 6 - 12" aft of the transom.

If a suitable fitting were fixed directly above the outboard bracket, this could be used as an atachment point for a tackle to raise the outboard for mounting.

Similarly, a fitting over the boarding ladder could be used as an attachmetn point for a tackle to help bring an MOB back on board over the stern.

In addition, the arch could be used to mount a solar panel, and perhaps provide a stern support for a boom tent, or a bimini for cockpit shade at anchor.

These are some thought.

Is the idea worthwhile, and is it practical?

Ray

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What a good idea. I'd always envied the arches you get on 40 footers but why not have one on a little boat? I've drawn a picture of one on my Parker 21 and it looks quite good! Bit like a 70's formula 1 car. I'll make one up in wood and attach it to the existing pushpit with jubilee clips and see if it gets in the way of anything.

Thanks, Geoff

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Hi...this will probably come through twice.....I recently built such an arch (portique) for my cat. It carries two solar panels and a wind genny, stern light and two cockpit / bathing lights, the flagstaff, and a line of loops to attach the bimini. As you suggest it inclines rearward so the crossbeam is over the bathing ladder, and is designed to carry 150 kg at midspan to assist lifting an MOB.
A nice addition is two short arms projecting rearward, from each end of the crossbeam, to carry pulley sheaves which lift the dinghy...i.e, davits.
And, as you suggest, it's clamped to the pushpit for extra stability.
I made it out of rectangular section alu-alloy tubing, 'cos I'm no welder, and it's easy, although I've worked with such material for years, not just on the boat. Needs painting, but looks really nice.
To my mind it really adds to the utility and safety of the boat.
Go for it!
Cheers...R

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Hi - the Boomaro 22 - this is the same as the Jaguar 22 in the UK, so why not post this on the Jaguar website;-
<A target="_blank" HREF=http://myweb.tiscali.co.uk/westgatefamily/default.htm>http://myweb.tiscali.co.uk/westgatefamily/default.htm</A>
Good luck!

<hr width=100% size=1>dickh
I'd rather be sailing... :-) /forums/images/icons/smile.gif
 
Thanks.

I cannot weld and I had thought of getting a piece of stainless steel tybuing and having it bent to suit.

My first problem is what size tubing would be adequate. The next is to figure out out to attach it. Then, I have to find someone to bend it.

Any ideas on size?

How about attaching it to the pushpit using U bolts?

Would Al be better, or perhaps easier (and may be cheaper)?

Ray

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Hi Ray it sounds like a good idea however I really shudder at those obviously cruising sailboats with so much top hamper of biminis solar panels etc. I think you run the risk of making the boomaroo look like a floating caravan with annex and making it very heavy in the process. Iknow my Castle does not like weight down the back as it drags the transom and I wouldn't care for all the additional aero drag.
nevertheless I admire the DIY and would suggest about 25 mm ss tubing perhaps mounted to the deck and braced at the pushpit as it passes at an angle. It would make a great mast su[pport when towing but again with aero drag. PS can you take some friends of mine for a sail on LBG. Little Johny howler and his friend Dark Mark but please don't bring them back and no MOB recovery either.
Regards will

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Hi...I don't know the boat or the layout, but the maximum load will be the MOB at mid span, and if you know the span, that'll give you the size tube you want for the cross piece. Then the over hang plus the MOB will give you the resistance required for the vertical bits, and the supports. Imagine an MOB exercise in a windy sloppy situation, and adjust sizes to suit.
My cat is obviously much wider, but I used 35 times 55 mm rect. ally alloy tube doubled up for the verticals and an amazing construction using laminated ally and ply for the cross piece. I guess that's irrelevant for your boat, but I did use u-bolts to clamp the "portique" to the push-pit.. What is the tube size of the pushpit?
I imagine you have something like a metre between the vertical supports? Then some square ally tube say 40mm by 3mm wall thickness might do it, verticals and cross piece as well.
Try it out with bits of wood. That's what I did, in the garden. Swung from the cross beam, adding thickness till it felt right. Then replaced it with the ally bits later. Not brilliantly scientific, but at least I KNOW what it will take!
I cannot comment on the top hamper effects referred to by the gentleman above, 'cos I don't know the boat, but again, try it out in mock-up mode with bits of wood, to get an impression of the finished result.
Hope that helps.
Cheers....R

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I take your point. I was thinking of a bimini only at stops.

Surely the weight of the SS tubing involved woudl not be great?

I had thought of simply fixing it to the pushpit with U bolts.

I don't think your friends would like to sail with me. I am too much of an amateur.

Ray

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Thanks Rohorn.

I like your scientific approach - perhaps a lack of theory, but a good experiment nonetheless.

I think my puspit is probably 25mm SS tubing - must check.

I presume that SS would be stronger than Al.

A mock up sound s like a good idea.

Ray

<hr width=100% size=1>Heat Wave
 
Hi....Oh, there was plenty of calculation too, but I didn't trust it. One thing....if you use aluminium alloy, such as Anticorodal (Al-Si-Mg), and you use stainless nuts and bolts and U-bolts, and you clamp it to the (presumably) stainless pushpit, apply Duralac (Zinc chromate, I think) liberally at the contact points to neutralise the corrosion risk. I'm sure you know all about the dissimilar metals problems in marine environments. You'll find Duralac in serious chandlers.
Weight for weight, heat-treated A-alloy is as strong as mild steel. The stainless tube could therefore be thinner and perhaps a bit lighter, but check the quality...sometimes it's drawn seamless, which resists corrosion more, has more uniform properties. Sometimes it's welded (seam) which could interfere with any bending you do, depending on the radius. Seam welded tube will not be evenly tempered, and will always show signs of rust along the seam.
25 mm SS tube is just about the universal size for pulpits and push pits. Same as mine.
Cheers....R

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