bent mast

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grego

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Mar 30, 2010
10
macgregor venture 22 saint georges island
I live in the annapolis maryland area the mast was stepped and stored on the boat covered with a tarp ,we had 24 + inches of snow this winter and the weight of the snow on the tarp bent the mast .the bend starts about 4-5 feet up from the deck there is no kink to the bend the bend is towards the aft any ideas to re bend the mast or source to replace cheap? posted on the mac owners forum and got several great ideas just looking for as much info as possible ,also will the re bent mast assuming no kinks be any less safe as far as structure? the boat is a 76 MacGregor venture 22footer100_2579.jpg
 

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Nov 22, 2008
3,562
Endeavour 32 Portland, Maine
I remember an article in "Yachting" back in the 60's about a large racing boat that rolled down so that the spinnaker went in the water and the pole came back and folded up against the shrouds. The compression load this put on the mast bent it and they had to limp home.

The mast was lashed down and the end lifted with a crane to bend it straight again. There was a picture of it show bent an unbelievable amount. The article claimed that the mast would be stiffer afterwards because of the work hardening.

So, there is a precedent for tying in between trees or other solid supports and carefully pulling it the other way with a tackle to straighten it. I'm not making any claims that it will work in your case though. If you've got to junk it anyway, you haven't much to lose.
 
Jan 13, 2009
394
J Boat 92 78 Sandusky
Call your insurance agent. Aluminum is a funny material and work hardens rather easily. Bending it back to shape might work but at the risk of a catastrophic failure later. Not worth the risk. Bending and unbending a 34 year old thin wall piece of aluminum tubing might not be such a good idea.
 

higgs

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Aug 24, 2005
3,715
Nassau 34 Olcott, NY
You can always try cranking down on the forestay to bring it back, but you will never know if the mast's integrity is intact.
 

higgs

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Aug 24, 2005
3,715
Nassau 34 Olcott, NY
I would probably do just what I said above and, assuming things straightened out, take her out in progressively windier days and hope for the best. McGregors are pretty lightly built and should not be pushed too far anyways.
 

Benny

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Sep 27, 2008
1,149
Hunter 320 Tampa, FL
Do you have insurance? Accidental damage as described is usually covered by boat policies minus a deductible of course. It is possible to straighten a bent mast but it is not easy. The bend as you may see is a gradual arch and the application of opposite forces at just a few points may easily result in a crooked stick. It occurs to me that perhaps utilizing a technique from automobile collision specialists for straightening frames could work. Lay out and attach the mast between two unmovable anchor points (trees as mentioned) and attach a rachtet puller (2000 lbs or larger) to one end. The idea would be to gradually strech the mast while applying heat to the bend area. It could be kept under tension for a couple of days and multiple heat and cool down cycles to see if it retains shape. It's just an idea but if it does not work not much would be lost. Good luck
 

Ross

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Jun 15, 2004
14,693
Islander/Wayfairer 30 sail number 25 Perryville,Md.
Trees are good anchor points. multiple come-a-longs and pieces of webbing would give a good chance of success. There isn't much to loose and you will proably have to go past straight to allow for spring back. It really isn't too badly bent.
 
Jul 5, 2007
196
Kenner Privateer 26 schooner, Carlyle Illinois
you should be able to straighten a V22 mast without too much effort. You need to determine the area and length of the bend. Position the bent area over a fulcrum point that is long enough that it won't cause a kink, and will hold one end of the mast 2 or 3 feet off the ground. If the bend is nearer one side; park a vehicle over the short end of the mast, and pad the point of contact. Bend the mast past straight, so it will take a new set as it springs back. I straightened a fairly heavy wall 33' mast by myself in that way.

I've seen aluminum arrows of the same type of aluminum, straightened many times with no real loss of strength.
 
Dec 2, 2003
1,637
Hunter 376 Warsash, England --
In former days I was a keen Star boat sailor. Stars have masts of similar size to yours and they regularly get bent by rigging wire failures etc.
I was often in great demand at regattas because they used to stand me with my back to a lamp post whilst two other guys held the mast at each end and forced the bent part against my stomach. They pushed and pushed until the mast was bent straight - it was a struggle - all the while ignoring my screams.

Yes it is simple to straighten masts as long as one has a nice soft cushion to use at the point needed to be straightened. The technique is to work along the spar doing a little at a time.

I would not recommend using heat as you would never get it up to softening point over the length and so heating would not soften the aluminium, which will already be WP treated (solution pickled) to get the desired surface characteristics. Heating might ruin the degree of hardness so carefully engineered into the aluminium.
Best solution would be to get a new one on insurance and straighten the original and keep it as a spare.
Why not visit a mast maker and ask them to straighten it as I believe they do it all the time with new extrusions!!!

See also:- http://www.azom.com/details.asp?ArticleID=2860#_Three_Point_Bending
 
Nov 6, 2006
10,151
Hunter 34 Mandeville Louisiana
Looks like the bend is all between the spreaders and the mast foot. Like Ross and others, I believe that if ya anchor it with a tree or something really strong just below the spreaders and opposite anchor at the apex of the bend… then carefully apply pressure to the mast foot, ya can straighten it..Use something like a big pad to spread the load.. The mast will want to twist so it will have to be really secure from rotating on axis.. Pull some and check and eyeball what is happening.. ya may have to move the pull point and anchor points as you work it to get it straight. The mast will work harden, as Donalex says, so you pretty much have one shot at getting it right (I agree with no heat).. be very gentle but firm, and slowly approach the “straight” shape so ya don’t overbend. Good luck with it.. It took only 300 pounds or so of snow (Not shrink wrap, right?) to do that so it is not going to take a lot of force to straighten it..You might even be able to support it at the foot and spreaders and, using sets of two concrete blocks tied together, simulate the snow weight (in the opposite direction) by starting at the supports with a set and placing/moving additional sets toward the apex of the bend. Make sure the blocks hit the ground before the mast gets bent in the opposite direction. Because the load in the upright mast there is mostly compression while sailing, the mast should be really straight to avoid a collapse.. I mean maybe an inch to an inch-and-a-half max over the piece from the spreaders to the foot. (ya ought to be able to get it better than that).. That mast is deck stepped so pulling on the stays won’t cure it..
 
Nov 22, 2008
3,562
Endeavour 32 Portland, Maine
be very gentle but firm, and slowly approach the “straight” shape so ya don’t overbend.
In the case from the "Yachting" article I saw, the mast had to be over bent until it looked almost like an archery bow. I think they are going to have to over bend, let it back, check, repeat, repeat, repeat. It's going to be a slow and painstaking process.

In the "Yachting" case, they were dealing with a mast that costs as much as most of our boats so they could afford to have an engineer calculate exactly how much to over bend it in one shot. I'm not sure of the implications of trail and error here. The stick is toast in any case so, what's to lose?
 
Oct 2, 2006
1,517
Jboat J24 commack
I would cut some wood vee-blocks so the mast will stay still against your pull points and then use a chain-hoist to pull and a tape measure to check each pull

Your going to have to overpull to reach the materials yield point and you could go and 1/8 to FAR and get and overbend in the other dirrection
 
Nov 22, 2008
3,562
Endeavour 32 Portland, Maine
Do you know how far the mast was deflected to bend it? You'll probably have to go about an equal amount in the opposite direction to straighten it.
 

BobM

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Jun 10, 2004
3,269
S2 9.2A Winthrop, MA
It is unlikely that you have boat insurance that will cover this on a small boat of that vintage, but if it was in your yard you should check your homeowners policy.
 
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