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post #1 of 8 Old 11-26-2013 Thread Starter
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Mast Crane Repair

On my aluminum mast, the topping lift mast crane (part that holds sheeve at top of mast) has worn sides where the wire topping lift (when loose) has rubbed the crane. It does not look to be a structural problem yet, but I would like to repair the cut grooves the wire has caused (and change the wire topping lift to all rope).

Would it be possible to have a welder "build up" the aluminum and then grind flat to restore to original condition? Or could welding cause more problems like a stress riser or change the properties of the original aluminum crane?
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post #2 of 8 Old 11-27-2013
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Re: Mast Crane Repair

easily done by a good welder, just take off the mast head and bring it to them, I have a friend who once did the same procedure for me on a motorcycle clutch housing
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post #3 of 8 Old 11-27-2013
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Re: Mast Crane Repair

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Originally Posted by casey1999 View Post
On my aluminum mast, the topping lift mast crane (part that holds sheeve at top of mast) has worn sides where the wire topping lift (when loose) has rubbed the crane. It does not look to be a structural problem yet, but I would like to repair the cut grooves the wire has caused (and change the wire topping lift to all rope).

Would it be possible to have a welder "build up" the aluminum and then grind flat to restore to original condition? Or could welding cause more problems like a stress riser or change the properties of the original aluminum crane?
Too much brain damage with that solution and unnecessary. Simply smooth out any rough edges with 80 grit sandpaper and then fill the grooves with Plastic Steel Putty. Smooth that down once cured that sand paper and "polish" with a fine grade of sand paper and you're done. Frankly, you could probably also do the job with gray Marine Tex:


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post #4 of 8 Old 11-27-2013
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Re: Mast Crane Repair

Since it is not a structural problem, you need only address chafing of your new halyard. Cut a piece of automobile door edge molding to length for each side and snap them into place. It's cheap, neat, clean, and easy.
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post #5 of 8 Old 11-27-2013 Thread Starter
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Re: Mast Crane Repair

Thanks for replys.

I was considering using the epoxy metal filler, but was concerned the UV rays could degrade in a short time- could paint to protect from UV, but then it becomes a maintenace issue.

I plan to un-step the mast to replace all standing rigging and mast tangs/bolts in a few months, so with the mast down, I could have a welder do some build-up. The mast head is welded to the mast- so not removable.

I do not think the groove is structural, but I would say it is borderline, and any moore groove cutting by the topping lift, I would say, would compromise the crane structurally. I'm the kind of guy who likes to fix things once, and not have to be concerned if my repair was "good enough."

Thing I don't want to do is introduce stress risers or change aluminum metalurgy while welding, and make the problem worse than it is.

I will shimmy up the mast and post a pic sometime over the next few days.

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post #6 of 8 Old 11-27-2013
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Re: Mast Crane Repair

Having read your original post more closely, I'd speculate that the wire portion of a wire-rope halyard wore the groove(s) in the crane when the shackle at the end of the halyard was affixed to a stanchion base and the halyard slapped around. This is what happened to my mast crane. I just wanted to cover the grooves to protect a new all rope halyards from wearing on the grooves in the mast crane. The door edge molding worked for fifteen years.
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post #7 of 8 Old 11-27-2013 Thread Starter
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Re: Mast Crane Repair

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Having read your original post more closely, I'd speculate that the wire portion of a wire-rope halyard wore the groove(s) in the crane when the shackle at the end of the halyard was affixed to a stanchion base and the halyard slapped around. This is what happened to my mast crane. I just wanted to cover the grooves to protect a new all rope halyards from wearing on the grooves in the mast crane. The door edge molding worked for fifteen years.
The gooves were actually cut before I bought the boat. I think the damage was done by the wire topping lift when the boat was under sail. With the boom off center, the wire topping lift will rub the mast crane sides. On the lower edge of the crane side, the aluminum is worn the full thickness of the crane material. I will post pic in the next few days.
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post #8 of 8 Old 12-23-2013 Thread Starter
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Re: Mast Crane Repair

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The gooves were actually cut before I bought the boat. I think the damage was done by the wire topping lift when the boat was under sail. With the boom off center, the wire topping lift will rub the mast crane sides. On the lower edge of the crane side, the aluminum is worn the full thickness of the crane material. I will post pic in the next few days.
Ok, Finally able to up load the pic. Best if you can zoom in to sheeve.
The first wire in pic is the topping lift- look at the groove cut in the crane support just behind this wire.
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Last edited by casey1999; 12-23-2013 at 04:42 PM.
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