Freeing Stainless Nut on Stainless Traveller Rail

[Fire99]

Evening gang,

My 'Snappie' Has a traveller rail bolted on the transom with a 22mm (or imperial equiv.) nut at each end 'glassed over' on the underside of the transom.
One end was so loose, the nut had unwound itself half a dozen turns, so was relatively easy to remove (once the glassfibre was chipped away that was over the nut),

The other end however, won't budge. The nut will move in the GRP (by moving the rail with the other end free) but it appears to have welded itself to the thread. ('Galling' perhaps? ) Even with a socket and fairly decent leverage it just wants to twist the rail. I've read somewhere about heating the thread to help free the nut. Would you suggest this?

Many thanks,


Nick

 

[nigelmercier]

Heating the nut may help, as would some Plusgas, or perhaps both:

http://www.amazon.co.uk/exec/obidos/ASIN/B0001P02RK/dolcetto-21

Can I say upfront that WD-40 is not the stuff to use. Perhaps this will head off some of the nonsense.

 

[Ammonite]

I'd be tempted to cut the nut off (hacksaw, grinder or nut splitter) and run a die up once off to clean up the thread if needed. If it is galling you'll destroy the thread with brute force. Not sure about heat. It all depends on how accessible it is. A pic would help.

 

[Fire99]

Impossible to cut the nut off without destroying the rail. Nut on the underside of the hollow raised transom in a recess that is only about 2 inches deep. Can only just reach it with a socket and extension.

 

[Fire99]

Hopefully attached is a pic which gives the general idea.

 

[Ammonite]

In that case tighten up the loose end and leave well alone

Sorry not to be more helpful - difficult to set what's possible without photos of the underside and if it's as tight as you say I imagine applying heat isn't going to be easy either

 

[Fire99]

Well my 'cunning' idea was to heat the rail on the outside, just above the transom since the nut is about 2 inches below where the heat would be applied. Somewhat concerned having a traveller rail that's very wobbly at one end.

 

[William_H]

I imagine this is a rail rod or tube that has a big nut only on the under side. There may be a flange of some sort on the top to enable you to tighten the bottom nut up. As said perhaps you should just tighten up the original loose end. It does however seem like this will leave the end with the seized nut still sloppy. Very frustrating. Heating of SS some inches away from the nut will not be very effective as SS is a relatively poor heat conductor. Of course any real heat will damage the fibreglass deck.
I can only suggest that you may end up cutting the tube or rod above the deck. You would then have shorten the other side recut a thread and refit the flange of some sort. (possibly a nut above and one below. All assuming there will be enough clearance for the tiller. Obviously try a lubricant first.
This kind of traveller does not normally have any control of car position. Some advantage when beating can be had by bringing the main sheet point (car) up to windward so bringing the boom over the boat centre line. I am alluding to the idea of a main sheet traveller system with control lines. This would have to be forward of the tiller. Some across a bridge mid cockpit or in my case at the bridge deck at the entrance hatch. Some cost of course in buying track and a suitable car. It might sail better though. good luck olewill

 

[Graham_Wright]

From time to time, my company produces a macerator shaft for the local chicken producers (don't ask!) together with a mating ring nut. The shaft is 50 mm in diameter and the thread pitch 1 mm.

We have had the nut gall to the shaft and a successful though laborious technique to free it is to apply some torque to the nut whilst tapping it around its periphery. It takes time!

 

[vyv_cox]

Galling is a form of adhesive wear, which is another way of saying welding. If the nut is firmly attached to the bolt it will not screw off no matter how hard you turn it. When a bottlescrew on my babystay galled I tried my very long adjustable spanner, nearly 2 ft long, with the body in the vice. The threaded part of the screw sheared but the threads remained firmly together. At worst you can only cut or otherwise machine it off.

 

[Fire99]

Many thanks everyone for the replies. Realistically it looks unlikely I'm going to be able to move the nut without destroying the thread on the rail so I may (for the sake of this years season, leave that end in situ temporarily.
OleWill - You are bang on the money to what I was trying to describe and yes there is little control available with the traveller car, other than it 'gripping' the rail which is a bit 'hit n miss'. I think, should I keep the boat beyond the end of the sailing year, a rethink on traveller position may be in order..

Thanks Muchly. These things can be all rather 'Galling'

 

[Ammonite]

Just a thought - could you use a dremel or drill with a flexi-drive and a small grinding wheel or is access too tight for this?

Something like this http://www.dremel.com/en-us/Attachments/Pages/ProductDetail.aspx?pid=225-01

 

[neilf39]

Can you get a pry bar onto the socket to give more leverage or is the space too limited? A 60cm handle gives lots more leverage than the standard 30cm socket set handle.

 

[ean_p]

if there is enough room below the nut then...cut off above fibreglass but below any flange...nut and threaded portion drop out of bottom.... cut off nut and/ or take to welder to weld back onto bar below flange then clean up threads and reassemble using lots of antigall stuff or even bronze nuts!.....welding about a tenner!

 

[Graham_Wright]

Galling is a form of adhesive wear, which is another way of saying welding. If the nut is firmly attached to the bolt it will not screw off no matter how hard you turn it.

See my post! We've done it twice now. It is a tedious procedure but when the job is worth a couple of hundred pounds, you persevere.

 

[VicS]

See my post! We've done it twice now. It is a tedious procedure but when the job is worth a couple of hundred pounds, you persevere.

The OP's sheet horse is similar to mine with probably even more restricted access. I dont think I'd be able to employ your suggested method on mine.

 

[Neil_Y]

Try ACF-50, it's very effective if corrosion is part of the problem.

 

[Fire99]

Thanks again for the suggestions. Vic you're probably right. There is around 5mm space either side (fore and aft) of the nut and the recess (from the nut to 'open space' in the locker, is a good 1ft. It's about as restricted as they come. No cutting or flame etc can be aimed directly on the nut without setting fire to the surrounding GRP.

 

[Fire99]

Just to add, the only way I can even see the nut is a strategically placed mirror on the floor of the cockpit locker.

 

[srp]

If it was my problem, I would cut through the grp around the flange ( Dremel or Fein multi tool) and then deal with removing the nut - probably by machining it off somehow if my experience of galling is anything to go by. The aim would be to keep the piece of grp that you cut out if at all possible, and to keep the horse itself intact. Re- cut the thread, epoxy the grp cutout back in position, and re- fit the horse using some molybdenum grease on the threads.
Obviously the repair to the grp is important to do properly because of the load from the main sheet, but it should be easy enough to make it at least as strong as the original.