Filling old holes in aluminium mast

[contessaman]

Hi guys,

any recommendations for what to do with old redundant holes in an aluminium mast? Filler ? Sealant? Rivet a bit of aluminium plate using existing rivet holes ?

 

[Poignard]

I would use CT1, because I have it. But anything that fills the hole and stays put will do. All you are doing is filling a hole, not trying to restore strength.

 

[Tamar]

I've used miliput in the past also because I had it hanging around. Can sand it down once it's gone off hard

 

[contessaman]

Cheers chaps I've got both CT1 and milliput in the garage . I'll give those a go then failing any other suggestions

 

[VicS]

Cheers chaps I've got both CT1 and milliput in the garage . I'll give those a go then failing any other suggestions

Screw or rivet holes could simply have a pop rivet or a self tapping screw set in them provided having them projecting into the mast does not cause any problems. It wont hide them , but nor will Milliput/ CT1 etc , but they will looker neater than just old empty holes.

A larger hole can be covered with a plate riveted on

 

[arcot]

Screw or rivet holes could simply have a pop rivet or a self tapping screw set in them provided having them projecting into the mast does not cause any problems. It wont hide them , but nor will Milliput/ CT1 etc , but they will looker neater than just old empty holes.

A larger hole can be covered with a plate riveted on

I believe a structural filled hole is stronger than a hole.

Bolt .......or tight screw......

 

[contessaman]

I can access the inside because they’re at the top and I’ve got the mast head off the mast. Maybe some aluminium plate on the inside shaped to the curvature of the mast and screws or rivets into it through the existing holes? Bedded down in CT1?

 

[Poignard]

I can access the inside because they’re at the top and I’ve got the mast head off the mast. Maybe some aluminium plate on the inside shaped to the curvature of the mast and screws or rivets into it through the existing holes? Bedded down in CT1?

But is it necessary to go to those lengths?

If whatever was originally in the hole added nothing to the strength of the mast, how has removing it weakened it?

 

[LONG_KEELER]

JB Weld might be an option . I always have some onboard and at home.

It dries close to aluminum colour.

 

[contessaman]

JB Weld might be an option . I always have some onboard and at home.

It dries close to aluminum colour.

oh yes that looks good..

 

[Restoration man]

+ 1 jb weld

 

[PeterWright]

If the filled hole is any stronger than unfilled, the difference is infinitesimal.
I wouldn't go near your mast, or any anodised aluminium with any abrasive for rubbing down due to the risk of going through the very thin layer of anodising which would start corrosion, really reducing strength.

I see little point in filling the holes, but it might be worth applying some chromate primer to the bore of the hole to protect the naked aluminium from corrosion.

Peter.

 

[arcot]

If the filled hole is any stronger than unfilled, the difference is infinitesimal.
I wouldn't go near your mast, or any anodised aluminium with any abrasive for rubbing down due to the risk of going through the very thin layer of anodising which would start corrosion, really reducing strength.

I see little point in filling the holes, but it might be worth applying some chromate primer to the bore of the hole to protect the naked aluminium from corrosion.

Peter.

Filled holes with like material may replace some strength
.......aluminium bolts threaded in?

 

[Boathook]

What size are the holes ? I've used rivets in the past.

 

[bluerm166]

If the holes are of a normal rivet diameter ,up to 6,4 mm and distributed along the length of the mast at substantial spacing,as for e.g. old mast steps or an external mainsail furler , rather than gathered in a narrowish band or bands around one or more 'circumference' it is unlikely that they will significantly weaken the mast.Filling the holes with anything other than the original material magically restored will not add any strength,but rivets look the part.