Alum mast broken , suggested repair

[Force10 0]

20 foot mast, broken 2/3  of the way up. 
any suggestions to repair it

A replacement mast , even if adapted to fit would be a more likely prospect, but curious how it’s been done .

[WCB 404]

You really only have one option, to sleeve it. What class of boat is it?

 

[Major Tom 389]

Probably needs an internal sleeve with a greater wall thickness than the original mast wall thickness as well as an external sleeve wrapped around the front 60% of the section, could use a piece of similar extrusion with the track cut off for this.

the biggest problem is finding a round  extrusion that will be a tight fit inside the broken section, you might need to cut a price out if the length of the sleeve to allow it to close up so it will fit. The sleeve needs to be a decent grade alloy as well or it could easily end up with a permanent bend at the join.

Bonding everything together with Sparbond and monel rivets will help as well.

Good luck

[European Bloke 451]

A sleeved aluminium mast will never be the same again, particularly  one sleeved in that area. What's the insurance option?

[Terry Hollis 319]

If the mast broke because of a rigging failure the above suggestions are ok but if it is an old mast that failed for no obvious reason it might be fatigued and past it's use by life.

Have an engineer look at the break so you will know if it's a fatigue or ductile failure.

[Force10 0]

Terry, fatigue seems the diagnosis, thanks, it is probably past it’s sell by date, or this case SAIL by date.lol

 

the boat is a 1970 Chrysler Lone Star, 13 foot. V.Good except now the mast.

appreciate the reply’s, all of them. Cheers 

[fastyacht 1,559]

26 minutes ago, Force10 said:

Terry, fatigue seems the diagnosis, thanks, it is probably past it’s sell by date, or this case SAIL by date.lol

 

the boat is a 1970 Chrysler Lone Star, 13 foot. V.Good except now the mast.

appreciate the reply’s, all of them. Cheers 

LOL.

[Dart96 22]

We have a similar problem. Laser 2 blew over in recent storms. Mast broke at the shroud bolt really cleanly. Cost of a replacement minimum is £500-700+VAT and insurer will only pay £200. Boat is scrap unless repaired.

Having chewed it over,  we will be laminating an external epoxy glass sleeve (internal sleeving is not possible in this particular case due to the removable top mast which is a snug fit inside the section that has broken off), probably 3-400mm each side of the break.

Because the sleeve cannot go all the way around the mast due to the mast track the edge closest to the track will be thickened to resist the compression and also pop rivetted to the mast.

We have used the laminate and then pop rivet technique on other boats where adhesion was likely to be poor or non existant. I intend to vac bag it all.

[European Bloke 451]

Loads of old wrecked L2 sat abandoned at clubs. Mostly not used cos the hull is so fucked they sink. Perhaps you could appropriate a new/used rig out of one of those?

They must be on the clubs to get rid of as abandoned, would go on the bonfire if they were wooden, list.

[blastfurnace 6]

if it doesnt need to be a tapered section ( sorry im unfamiliar with the lone star ) a straight section for a 13 foot dinghy wont be expensive. and probably not too critical on size of section ( if youre not racing and dont need to conform to class rules)  id suggest a couple of hundred bucks? for the section anyway.