mast rivets.

[pandos]

The mast on the boat has a join about 30inches above the deck. there is some corrosion around the rivets. I was going to drill them out and replace them with slightly bigger ones. I have seen differing advice on the type to use monel/ aluminium. and whether to put sealer on the rivit before it is put in or to punch out the pin after the rivet is expanded?

Advice based on knowlege would be appreciated.

thanks in advance.

tony.

 

[rjp]

The normal recommendation for masts is Monel - much stronger than aluminium (which tends to be too weak for load-bearing fittings) and corrosion resistant, but they need to be isolated from the aluminium of the mast with something like Duralac (a proprietary zinc chromate compound I believe). If you can't get it a decent paint would probably be better than nothing, but if you use nothing (as someone had done on some fittings on my mast) you will get corrosion around the rivet holes eventually. If I remember correctly I got my monel rivets from SeaScrew - good service but a bit steep on postage I think. If you need more info I can probably dig it out.
John

p.s. if you do use monel you'll need something like 'lazy tongs' to set them. You can't get enough pull using a normal hand riveting tool.

 

[William_H]

Around here the largest pop rivets in monel will be 3/16inch or the metric equivalent so you may not be able to fit larger rivets. Nevertheless it will make you feel more confident to fit new rivets. Just use lots of Duralac and you will need gutsy rivetter. olewill

 

[Birdseye]

For mast sized rivets and unless you are built like King Kong, you will need one of those concertina type riveters - cant remember their proper name but they have a sort of lattice like structure. Monel is hard, one reason it is used in masts and in aircraft.

 

[rjp]

Youcan get larger Monel rivets in uk, I got some 1/4inch last summer, but they are pricey. Fortunately most of my needs were met by 3/16inch which are a lot cheaper.

John

 

[oldsaltoz]

Check out a good tool store and pick up the attachment for a drill that makes riveting a joy but a tad expensive.

Andavagoodweekend......