zwaky

Why does my mast do this?

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I am restoring a frankenstein flying junior.

Along the mast runs a groove in which the mainsail slides into. HOWEVER on the top of the mast, the groove widens and the sail comes out. This gives it a weird shape to the sail and gets completely stuck when I try to lower it.

What can I do?!?

2lu6jcp.jpg

 

 

2it1n5w.jpg

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replace the mast :blink:

 

looks , like the sail track has been stretched ...................

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Hammer it closed again.

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7 minutes ago, ortegakid said:

Hammer it closed again.

cheaper option :)

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Or, for more control, might try squeezing the slot together with a large pair of vise grips.

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WOuld you heat it first?

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You said Frankenstein.... did you/someone flip the extrusion? Looks like the bottom groove of a lot of masts that have a wide slot for gooseneck slide,  vang plates etc

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The opening is definitely the top of the mast.  It looks manufactured that way, judging from how symmetrical and gradual it is. But since everybody seems to have never seen anything like it, I will go down the route of bending it closed. 

 

OR just rig the sail not all the way up...

 

29vjcee.jpg

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9 minutes ago, zwaky said:

OR just rig the sail not all the way up...

pic looks like full hoist ?

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1 minute ago, longy said:

No, those boats have a  high boom

cheers , actually now that you mention it we can see that from the pic in the OP .

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15 minutes ago, zwaky said:

, I will go down the route of bending it closed. 

concur , would try some type of clamping action rather than an engineers hammer ...........

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Looks like the mast has been tapered down the front edge, this will cause the track to open up if it is done before tempering, best solution is to gently panelbeat it closed..

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We had 20 FJ's at our sailing school that were in a constant state of repair. Widened Sail Track Syndrome was not uncommon, although it was usually accompanied by a mast bend. The hammer was the standard remedy laying the mast on a wooden bench, and laying a small piece of wood on the top of the widened section and pounding as required. Flip the mast a few times to ensure it is closed as evenly as possible.

Gotta love those old Rockall Sails. Must be mid 70's vintage.

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Here is an update on the situation.

 

The depth of the track is roughly 0.8" throughout the mast but goes to 0.6 where the track widens. Im not sure what to make of it.

The first photo. Where the bulge lowers goes a pulley which I removed.

33cad1f.jpg

 

71s76g.jpg

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MISSION SUCCESS

A vice, alongside vice grips was all that was needed.

I worked slowly with a mate and we did an okay job. Dam I am happy that this hurdle is surmounted.

We were also able to slightly recede the bulge inside by hammering the top of a metal plate.

 

2n6cxz.jpg

 

2nklzex.jpg

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Would a plate screwed across the top of the slot help to keep it from opening up again?

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Whatcha think ? Over-bending spread it ?   It is (was) impressively symmetrical

At least you don't have MY recurring problem of the top 5 feet breaking off at random.

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On 10/2/2018 at 8:25 PM, zwaky said:

MISSION SUCCESS

A vice, alongside vice grips was all that was needed.

I worked slowly with a mate and we did an okay job. Dam I am happy that this hurdle is surmounted.

We were also able to slightly recede the bulge inside by hammering the top of a metal plate.

 

2n6cxz.jpg

 

2nklzex.jpg

Sweet workshop, too

The one caution I have to suggest is that the metal will work-harden when you do this. I don't know what do do about this, other than once in a while check it for cracks around the area you hammered. That way you'll have some warning when it breaks!

FB- Doug

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16 hours ago, Steam Flyer said:

Sweet workshop, too

The one caution I have to suggest is that the metal will work-harden when you do this. I don't know what do do about this, other than once in a while check it for cracks around the area you hammered. That way you'll have some warning when it breaks!

FB- Doug

Annealing aluminum is really easy. You want to heat it up to just below it’s melting point, allow the crystal structure to relax (the heat allows the structure to straighten the body-centric-cubic crystals) and let it air cool.  Just use a blowtorch and “paint” the heat.

A good way to tell that you’re at the right temperature is to take a sharpie and mark the mast where you’ll heat it. You’re at the right temperature when the sharpie starts to fade.

this shouldn’t affect your beautiful gold anodization either. Anodization is actually an artificially oxidized layer that’s been dyed. You can actually melt aluminum and the anodized layer will actually hold the molten aluminum in a little bag.

Don’t stress the piece until it’s cooled all the way- it can cause a bumpy texture to form.

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7 hours ago, Connor.kainalu said:

Annealing aluminum is really easy. You want to heat it up to just below it’s melting point, allow the crystal structure to relax (the heat allows the structure to straighten the body-centric-cubic crystals) and let it air cool.  Just use a blowtorch and “paint” the heat.

A good way to tell that you’re at the right temperature is to take a sharpie and mark the mast where you’ll heat it. You’re at the right temperature when the sharpie starts to fade.

this shouldn’t affect your beautiful gold anodization either. Anodization is actually an artificially oxidized layer that’s been dyed. You can actually melt aluminum and the anodized layer will actually hold the molten aluminum in a little bag.

Don’t stress the piece until it’s cooled all the way- it can cause a bumpy texture to form.

That's very cool info, thanks. I have a couple of project masts laying around to experiment with. I've heard people saying they re-annealed their masts but was always very sceptical. https://en.wikipedia.org/wiki/Annealing_(metallurgy)

I'm guessing the process is somewhat different for carbon fiber spars................

FB- Doug

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I think you will get better results if you have your entire mast retempered, do you have any aluminium extruders in your vicinity?

All the rigs I taper I take to the extruders after welding and they re age the sections in the same oven along with other extrusions being tempered to a T6 hardness.

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