Repair a bent boom?

dancrane

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Looking at pics of the late Osprey, whose cockpit was 8ft 6" long, the boom end overhung the rear deck by a good 18", so it must be 10ft or 3m.

It's a very long way from new, of course.
 

William_H

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Point A, if you’re clobbered by a cruiser boom with any weight in the wind, the prescence or absence of fittings won’t make much difference. Extra holes, fair enough if it bothers you. And all the tracks I’ve come across have been a quite tight enough fit already. Fair enough if you have the sail made or altered, but no material thin enough would be strong enough otherwise.
I am aware of a death on Swan River some years back by boom hitting a head. However on a smaller boat I feel it almost inevitable. I have been involved in one and seen results of another recent head bash at our club. Much blood. All on smaller 25 or less boats. Bigger boats mecifully usually have a higher boom.
On my boom I was paranoid about fittings going into a skull. None on the sides. Yes I have been hit a few times with my boom. Usually not in a gybe but rather when moored with main sail up and flopping from side to side. It just hurts. Light weight carbon fibre seems to reduce inertia so damage. ol'will
Ah perhaps boom bash on head can be my excuse!
 

Tranona

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Not if it’s a tight fit you can’t. The after market ones I’ve seen fitted like that do not move well enough in my view. I would, personally, find an alternative method.
The stackpack does not have to move to adjust the clew of a loose footed sail. My stackpack is actually attached to the boom with slugs as the sail is loose footed.

I have also used the awning tracks in the past on another boat with a wooden boom with a sail running on slugs in a track. worked well for 20 odd years until I had the sail converted to loose footed and a new stackpack with slugs.

There is a wide variation of stackpacks and my first one was one of the very first made by Kemps. The latest 2 also Kemps and we just sat down and worked out the best way of doing it for the specific boat.
 

Chiara’s slave

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I am aware of a death on Swan River some years back by boom hitting a head. However on a smaller boat I feel it almost inevitable. I have been involved in one and seen results of another recent head bash at our club. Much blood. All on smaller 25 or less boats. Bigger boats mecifully usually have a higher boom.
On my boom I was paranoid about fittings going into a skull. None on the sides. Yes I have been hit a few times with my boom. Usually not in a gybe but rather when moored with main sail up and flopping from side to side. It just hurts. Light weight carbon fibre seems to reduce inertia so damage. ol'will
Ah perhaps boom bash on head can be my excuse!
I”m aware of 2 boom related fatalities. In both cases the victim was knocked overboard and drowned.
 

Daydream believer

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I am aware of a death on Swan River some years back by boom hitting a head. However on a smaller boat I feel it almost inevitable. I have been involved in one and seen results of another recent head bash at our club. Much blood. All on smaller 25 or less boats. Bigger boats mecifully usually have a higher boom.
On my boom I was paranoid about fittings going into a skull. None on the sides. Yes I have been hit a few times with my boom. Usually not in a gybe but rather when moored with main sail up and flopping from side to side. It just hurts. Light weight carbon fibre seems to reduce inertia so damage. ol'will
Ah perhaps boom bash on head can be my excuse!
perhaps you would be better off with a MOBO
Inexperienced crew do sometimes hit their heads, but if the skipper is any good he can go a long way to preventing that ;)
 

Refueler

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You cannot bend that back without first sorting the dent ... which needs to be pulled ...

Once pulled - then the boltrope slot needs support when metal worker straightens the boom ... to avoid the slot closing up.

Once straight - metal worker then welds the crack.

Any decent Metal Workshop should be able to sort that ....
 

Geoff Wode

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Hi Dave,

I believe the Duette has the same boom section but probably less chance of picking one of those up.

What did the original Sonata rig have before the racing fleet moved to the newer Selden mast? Might be an avenue worth going down? Maybe email the Sonata Association, check if they have spares or old kicking about?
 

Geoff Wode

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Yes, the Sonata is a national one design and has its own association. Never had anything to do with them but they look a friendly bunch.

Home : Sonata Sailing

I think the website has recently changed to SCM and it looks a bit clunky but the info is there.
 

ProDave

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Yes, the Sonata is a national one design and has its own association. Never had anything to do with them but they look a friendly bunch.

Home : Sonata Sailing

I think the website has recently changed to SCM and it looks a bit clunky but the info is there.
Thanks I have sent a message to them.

What is the likelyhood of an IYE or Proctor boom if the right size fitting to a Z spars gooseneck without too much engineering alterations?
 

Geoff Wode

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Thanks I have sent a message to them.

What is the likelyhood of an IYE or Proctor boom if the right size fitting to a Z spars gooseneck without too much engineering alterations?

Not entirely sure. Just based on a hunch that they’ll be similar proportions/ length.

Another option is to ask Zspar what boats were fitted with that section so you have a better idea of where to look. I know it’s different to the larger Hunters of the same period.
 

oldbloke

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I would think you could buy, or have made, a new prong for the gooseneck to fit any boom you buy. Most gooseneck assemblies are easily dismantled
 

Jim@sea

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Although its years since I had a bodyshop and straightened car bodies I would be inclined to try and straighten it myself, perhaps buy for around £120 a 10 ton portapower off eBay fine somewhere to place the ends of the boom at each end and s 8ft 4"x4" strong post and try and portapower it straight,, it wont be perfect but usable, then advertise the portapower back on eBay as only used once at £75, Worth trying before having to buy a new boom.
 

Daydream believer

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Although its years since I had a bodyshop and straightened car bodies I would be inclined to try and straighten it myself, perhaps buy for around £120 a 10 ton portapower off eBay fine somewhere to place the ends of the boom at each end and s 8ft 4"x4" strong post and try and portapower it straight,, it wont be perfect but usable, then advertise the portapower back on eBay as only used once at £75, Worth trying before having to buy a new boom.

In a proper repair the damaged section would be cut out on 21/2 sides leaving the opposite side & the track in place. The boom would then easily be pushed into a straight line & clamped to avoid distortion during welding. Then new sections welded in.

One does not need specialist equipment to bend it. Just take it to the sailing club. Put it between the bearers of a heavy cruiser trailer & put a hydraulic car jack under it. Some 4*2 at bearing points to spread the loads . Then jack it in to place.
He could just lay it on the driveway with some wide pads of18mm ply about 3 ft apart & 12mm ply in the middle under it to prevent over bending . Then make a ramp of 3 layers of 18 ply or a strong board to it & gently drive the car up the ramp so it gradually applies pressure as the car goes up the ramp. Thus pushing the boom down on to the 12mm ply. It should spring back the 6mm if it over straightens. Just do a bit at a time. Force some hardwood into the lips of the groove first to avoid the possibility of it closing up. You could use a bit of the plate I am mentioning below if it fits. You may have to clamp the ramp to the boom with a G cramp to avoid the ramp flipping the boom out like a tiddlewink.
One has to accept that the wider vertical damaged side will remain damaged. The narrower top & bottom parts are damaged & the rounded corners will not go back in to place.
Then get a 100 * 5mm strip of aluminium about 500mm long & pop rivet it along the side of the boom with most of the rivets near the edges.Put one both sides if you like. File the edges of the aluminium to a slight round so it does not snag the mainsail.
Cost will be the aluminium, some new pop rivets.
Then of course there is the obligatory domestic with the wife as you direct her to drive the car up & she runs you over like a rampant stop oil protester:love: :cry:
 
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AntarcticPilot

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Others have noted this, but straightening the section will inevitably weaken it further; think of breaking a wire by bending it back and forth. I'm with those who say a) I wouldn't trust it as it is and b) I certainly wouldn't trust it if it was straightened. Where it is bent the metal is already severely fatigued; bending it back would add to that. And the bending forces when in use will slowly add to the fatigue at the bend, just where the bend is creating a stress concentration. So I'd expect it to be fine as it is right up to the moment when it breaks without warning, probably just when you're already having to cope with a sudden wind shift or gust. I'd suggest that the only safe repair would be to cut the damaged portion out and make up some sort of internal sleeve to rejoin the two parts, but it may well be simpler and cheaper to alter the gooseneck to take a different boom!
 

NorthRising

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Hi Dave,

I believe the Duette has the same boom section but probably less chance of picking one of those up.

What did the original Sonata rig have before the racing fleet moved to the newer Selden mast? Might be an avenue worth going down? Maybe email the Sonata Association, check if they have spares or old kicking about?
Original Sonata boom was Proctor. Sonata boom I think a little shorter than HH23 boom, check very carefully or saggy foot syndrome.
 

NorthRising

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Thanks I have sent a message to them.

What is the likelyhood of an IYE or Proctor boom if the right size fitting to a Z spars gooseneck without too much engineering alterations?
I did manage to get a Procter Sonata boom gooseneck jaws to fit a new Selden mast side gooseneck with no problem. But your problem with a Sonata boom is its slightly shorter than the HH23 boom - will you be able to tension the mainsail foot adequately measure very carefully? I can give you access to a Sonata proctor boom for measurement comparison purposes if you want.
 

Refueler

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IMHO - as I posted earlier =- trying to bend such a form back straight will make the track guide close up and really make a mess ... it needs dent pulling out .... then form put into the track to prevent it collapsing before then straightening ..... finally weld the cracks.

Another way would be to cut away bottom face ... pull dent ... insert form into track preventing collapse .. straighten - then have tapered sheet installed inside to strengthen the area BOTH sides .... then close up by welding bottom piece back in.

I've seen riggers repair masts / booms / outriggers same way.
 
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