Thread: Mast Repair
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Ian Malcolm
 
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Default Mast Repair

Len wrote:
It worked fine for me...
The pictures were a bit blurred but it seems the part that is
connected (mastfoot?) could be drilled loose and you could a) use
slightly bigger (thicker) rivets on the old places and b) drill a new
hole next to the one ripped open.


After looking at the damage, I'd be concerned about the end of the mast
opening up slightly and coming off the step on the edge of the mast foot
casting. If this starts to happen, total failure could occur in a
very short time with the mast wall peeling back as it is forced over the
foot like peeling a banana. How far it will go and is the rig going to
stay up are the critical questions. I'd NOT be happy with just
re-riviting it.

You cannot effectively weld many grades of cast aluminium. If you are
going to have this welded, ONLY GET THE CRACKS WELDED. The foot casting
should still be fitted with rivits. The damaged area should be sleeved
with a rivited on sheet of aluminium on the outside extending a couple
of inches up the mast and the new holes for the foot drilled through
this and the mast wall. This will prevent it spreading as described
above. To shape aluminium sheet to fit, it will have to be annealed.
Ideally it would be heat treated to harden it before riviting it in
place but some alloys age harden to a fair extent at room temperature.
Best talk to a rigger. If you DIY this, you NEED to use Duralac on the
rivits and all surfaces in contact unless you are using a structural
adhesive.

If you have enough thread left on your turnbuckles to take up half an
inch and still have plenty of range for adjustment, cut off the damage
and have done with it. I would only raise the tabernackle as a last
resort.

--
Ian Malcolm. London, ENGLAND. (NEWSGROUP REPLY PREFERRED)
ianm[at]the[dash]malcolms[dot]freeserve[dot]co[dot]uk
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'Stingo' Albacore #1554 - 15' Early 60's, Uffa Fox designed,
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