Applying mast hoops in situ / steaming?

[prv]

I know it's an old chestnut of a question, but I have two replacement mast hoops that I need to get onto KS's mainmast, and one onto the mizzen. Although the masts are down, they have fittings at masthead and base which I don't want to remove and which prevent me sliding the hoops over the ends.

The hoops have had the rivets drilled out (I asked Classic Marine to supply them loose, as offered on their site, but they ignored that request) and I think the spirals open up wide enough to wind onto the mast. If so, great, and I will then epoxy them back together, partly because I don't have the rivets and partly since it will add extra strength.

However, if I can't slip them onto the mast without risk of breakage, I presume I'll have to think about making them a bit more flexible using steam. I've never done this before, so any advice is welcome.

Pete

 

[srp]

I use a wallpaper stripper to generate the steam, but if you haven't got one, or the 240v available to run it, then you could stick them in a pan of boiling water on the galley stove. 10 to 15 minutes should be enough assuming they are around 10mm thick.
Have some thick gloves handy, and a couple of small G cramps or similar to clamp them in position when you've sprung them over the mast. You'll have to leave them for a good few days to dry out before using epoxy, so it might be worth considering PU adhesive instead, which actually relies on moisture to cure. Use the existing rivet holes with a temporary nail through to line the joint up, then you can stick the rivets through at a later date.

 

[prv]

I use a wallpaper stripper to generate the steam, but if you haven't got one, or the 240v available to run it, then you could stick them in a pan of boiling water on the galley stove.

Do you mean actually immerse them in the water? I didn't know you could do that. It certainly sounds easier than trying to control airborne steam.

Cheers,

Pete

 

[srp]

Yes, just stick them in the pan. You just need to heat and saturate the fibres. With a long piece of timber it's much easier to use steam, but with something this size it's a nuisance to have to make up a special steam box when a saucepan will do just as well. I suppose you could use a trivet if you really wanted to, but there's probably no advantage in doing so.

 

[prv]

Thanks - I'll bear that in mind for my future bending needs, but I'm pleased to say that I managed to wind a hoop onto the mast today, dry, without any real trouble. So much for all the dire warnings I've read that this can't be done

(It was peeing with rain, so I was just test-fitting it with my head under a tarpaulin to see whether I'd need to bring steaming paraphenalia down to the boat tomorrow. The forecast is sunny, so hopefully I'll get both of them on and epoxied.)

Pete

 

[prv]

To complete the story (almost):

I got the two new mainmast hoops on and glued today. Put a bit of scrap wire through one of the rivet holes to keep it all lined up, but the actual fixing was supplied by plenty of cable ties holding the layers together while the epoxy goes off.

Just need to get the ties off again next weekend, then a rub down and onto the varnish. Not sure how I'm going to get a decent coat on the inside of the hoops where they have to hang on the (horizontal) mast while drying - I guess just a different place each coat and then patch up the last one.

I'm not going to replace all the rivets, but I might put something through the last hole to help stop the "tongue" lifting. Don't have the proper thing; might end up using a small stainless nut and bolt. Unless I can find some seriously chunky copper wire somewhere in the shed...

Pete

 

[old_salt]

Get the proper nails for the job you will only regret it every time you look at the nuts and bolts or a piece of chunky copper wire.
If you feel you may have a problem riveting them just ask and I am sure you will get good advise form the peeps on here.
I have a few ideas to help having riveted up 60+ new ribs boilers and other engineering odds and ends.
This guy on ebay has coper nails not too expensive.
They look round ones but I am sure you will find the square ones on there as well.
They end in hrs but you have the info to follow them up though ebay email.
http://cgi.ebay.co.uk/copper-nails-/110663190056?pt=UK_DIY_Material_Nails_Fixing_MJ&hash=item19c40a4628

also nails and roves here:- http://shop.ebay.co.uk/i.html?_kw=copper&_kw=boat&_kw=roves&_dmpt=UK_CarsParts_Vehicles_BoatEquipment_Accessories_SM&_npmv=3

 

[prv]

A "piece of chunky wire" with its ends peened over is surely indistinguishable from a rivet!

I wasn't planning to replace all the rivets - it doesn't seem necessary with the whole thing saturated with epoxy. The only place I might do is at the end of the strip, if it seems like it might lift and be torn away. Alternatively, I might just shave it away smooth so there's nothing to catch.

Pete

 

[old_salt]

Hi Pete.
My apologies.
I was thinking a piece of wire simply passed though and wrapped round.
A thick piece with a rove and riveted and snapped up should do the job a treat.
I was also thinking of the ascetic looks as well.

Cheers David.