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Straightening Masts |
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buckroger
Newbie Joined: 08 Jun 11 Location: UK Online Status: Offline Posts: 4 |
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Topic: Straightening Masts Posted: 06 Oct 11 at 4:49pm |
Any tips for straightening aluminium masts? Mast in question is looking rather bowed at the foot. It might be a write off but potentially salvageable if carefully straightened.
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Iain C
Really should get out more Joined: 16 Mar 04 Location: United Kingdom Online Status: Offline Posts: 1113 |
Post Options Quote Reply Posted: 06 Oct 11 at 5:21pm |
Pics?
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RS700 GBR922 "Wirespeed"
Fireball GBR14474 "Eleven Parsecs" Enterprise GBR21970 Bavaria 32 GBR4755L "Adastra" |
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Neal_g
Far too distracted from work Joined: 07 Oct 07 Location: United Kingdom Online Status: Offline Posts: 323 |
Post Options Quote Reply Posted: 07 Oct 11 at 7:47am |
aluminium masts will straighten bu then bend and snap in exactly the same as the metal has already been stressed and weakened so its either leave it bent or get a new one im afraid
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(Redoubt Sc)
Miracle 4040 GP14 13407 Crewsaver phase 2 range now available to buy online on at http://www.gibsonsails.com |
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Contender 541
Really should get out more Joined: 05 Dec 05 Location: Burton on Trent Online Status: Offline Posts: 1402 |
Post Options Quote Reply Posted: 07 Oct 11 at 8:07am |
Sorry, but I must make this correction
Aluminium hardens when bent, it does not weaken - of course the further you bend it, the thinner the section and the lower the strength of the cross sectional area
To answer the original point - yes you can straighten it, but it can be hard work and rarely works the same again. Just put the mast under an immovable object and a fulcrum under the bend and then lean on it!!
There are professional straightening companies that are used in industry (trust me on this, as strange as it sounds they do exist) and one of these may be able to advise you better
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When you find a big kettle of crazy it's probably best not to stir it - Pointy Haired Boss
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gordon1277
Really should get out more Joined: 24 Mar 10 Location: United Kingdom Online Status: Offline Posts: 665 |
Post Options Quote Reply Posted: 07 Oct 11 at 8:28am |
Hi
It seems very odd that it has bent near the foot, normally it is near the spreaders or top. What happened? I have straightened a few and they seem to have been OK but not this low down, give it go but make sure you use a rounded post to bend it round. Take photos first for your insurance company in case you need it. Good Luck. |
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Gordon
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JimC
Really should get out more Joined: 17 May 04 Location: United Kingdom Online Status: Offline Posts: 6648 |
Post Options Quote Reply Posted: 07 Oct 11 at 8:42am |
Like a lot of these things the most important thing to do is to find someone who's done it before... There is a knack to it...
As a rule of thumb though any sign of creases or distortion in the metal means you are unlikely to be successful. If you are insured for the damage then your insurance company may well have an interst in finding you someone who can do a good job... |
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mole
Groupie Joined: 02 Feb 06 Location: United Kingdom Online Status: Offline Posts: 43 |
Post Options Quote Reply Posted: 07 Oct 11 at 8:58am |
If you plan to do it yourself make sure you place it on a fulcrum without a point load. i.e. use something like a sand bag. When applying the pressure to bend, do not attempt to straighten with applying a single bend alone, instead use a combination of single over extensions and a 'bouncing technique'. This minimises the chances of over straightening and failure.
If you are concerned about the strength of the finished item, you could also consider a sleeve or doublers to put strength back in the mast as this is to wards the bottom. Although this will affect the bend characteristics of the mast considerably. hope that helps
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tickel
Far too distracted from work Joined: 21 Dec 05 Location: United Kingdom Online Status: Offline Posts: 408 |
Post Options Quote Reply Posted: 07 Oct 11 at 9:12am |
I have a special hawthorn tree with two trunks that spread as they go up. Put the mast in the 'V' and adjust its position then lever. It has worked many times. This is OK for me as I have lots of trees but I suppose wandering through the park carrying a mast looking for suitable trees could look odd.
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tickel
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Barty
Far too distracted from work Joined: 16 Mar 04 Location: Scotland Online Status: Offline Posts: 240 |
Post Options Quote Reply Posted: 07 Oct 11 at 12:30pm |
I've used the drive and wheelie bins before. Just turn the mast so the bend high point is off the ground and place a wheelie bin on it and then as you put rubbish/grass cuttings in it gets heavier and gradually straightens the mast. Took me a week to get a straight mast but rather this that trying to straighten it against a tree and by hand. You have no idea how much force is needed to straighten it and there is a good possibility that applying hand force will over correct it or do more damage..........doing it slowly is the key!!!
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robinft
Far too distracted from work Joined: 18 Jun 04 Location: Thorpe Bay YC Online Status: Offline Posts: 252 |
Post Options Quote Reply Posted: 07 Oct 11 at 4:39pm |
I use a suitably cushioned road trailer. |
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