installing mast track

[vientoman]

when installing the fasteners that hold mast track onto an aluminum mast with stainless fasteners, is there a preferred thread compound to use? should it be a thread locker like medium strength locktite or some other type of magic product? In my case, I am installing harken CB track onto an aluminum mast with 160 5/16 - 18 flat head screws.......lots of drilling and tapping to do.

Thanks all

[44'cruisingcat]

You need to use something that will electrically isolate the dissimilar metals. Duralac, ( http://www.llewellyn-ryland.co.uk/downloads/duralac.pdf ) for instance.

I screwed my track to the mast, but in hindsight, I think I'd use monel rivets if I were doing it again.

[Chasing Summer]

I agree ... I took the track off my old boom which had aluminum rivets ... completely corroded. I also removed stainless steel, or tried to remove them from the cleats on the mast. Ended up grinding them off flush. Monel rivets is the way to go. Put them in once. You don't have to worry about them, and if you ever do want to remove it you just drill it out. Also, rivets means a much smaller hole in the mast than a bolt.
Good thing to keep on the boat: various lengths of both 1/8 & 3/16 monel rivets ... and a good gun that the head can adjust to different angles.

[roverhi]

SS fasteners in aluminum cleats on a mast corrosion weld themselves to the aluminum cleat not the mast. As long as you us TefGel, LocTite, or some other insulator, drilled and tapped SS machine screws work just fine. Unless you have access to air and a pneumatic pop rivet gun, setting those rivets is way harder than drilling and tapping. Monel or SS pop rivets take 'Popeye' forearm and grip strength to 'POP' with a manual PR gun. If you are able to use a pneumatic PR gun, rivets are easier to use.

3/16" pop rivet take about the same size hole as #10 machine screw.

Originally Posted by Chasing Summer

I agree ... I took the track off my old boom which had aluminum rivets ... completely corroded. I also removed stainless steel, or tried to remove them from the cleats on the mast. Ended up grinding them off flush. Monel rivets is the way to go. Put them in once. You don't have to worry about them, and if you ever do want to remove it you st drill it out. Also, rivets means a much smaller hole in the mast than a bolt.
Good thing to keep on the boat: various lengths of both 1/8 & 3/16 monel rivets ... and a good gun that the head can adjust to different angles.

[44'cruisingcat]

Originally Posted by roverhi

SS fasteners in aluminum cleats on a mast corrosion weld themselves to the aluminum cleat not the mast. As long as you us TefGel, LocTite, or some other insulator, drilled and tapped SS machine screws work just fine. Unless you have access to air and a pneumatic pop rivet gun, setting those rivets is way harder than drilling and tapping. Monel or SS pop rivets take 'Popeye' forearm and grip strength to 'POP' with a manual PR gun. If you are able to use a pneumatic PR gun, rivets are easier to use.

3/16" pop rivet take about the same size hole as #10 machine screw.

What happens is that the aluminium in contact with the stainless steel turns to salt. (AlCl) And salt doesn't hold the screws in very well.

Even though I used Duralac, I still have had a couple of these screws fall out.

If a screw in a sailtrack comes loose at the wrong time, you may not be able to get your mainsail down.

Which Is why I suggested rivets. But you still need to use Duralac or Tefgel.

[delmarrey]

If you use SS screws w/o TefGel you'll never get them back out w/o braking something.
Since the track is aluminum I'd go with 1/4" aluminum rivets. If the holes in the track are 5/16", you can make sleeves from aluminum tubing or order nylon bushings.

But being a mast track the holes shouldn't be over 1/4". Why 5/16-18 screws?

Harken does make a fastener kit too.>>> http://www.harken.com/productdetail....5805&taxid=519

[capt-couillon]

Lanocote (Boat Lubricant Lanocote) Not as sexy as TFE gels, but also useful for lubing turnbuckles. clevis pins, etc. Cheap, works well, lasts forever. Old school but, don't fix something that works.

[Terra Nova]

TefGel.

[Wight Mistress]

Hi All, I hear you all discuss fitting a Harken track to a mast with screws or rivets etc, but is there a way to make use of the existing sail hank slot to fit the Harken track over it? I have a Fisher 34 ketch with a furling mainsail (behind not in-mast) and am addressing the mizzen mast with it's horrid plastic hanks that seem to make lowering a challenge, and I am future proofing the boat for sailing as we get older. Any ideas most gratefully received.
Steve

[Benz]

Blue Loctite on the screws will both isolate and keep them from vibrating out.
If the track has pre-drilled, countersunk holes, the OP may not have the choice of rivets. How do they work in chamfered holes?

[Wight Mistress]

Originally Posted by Benz

Blue Loctite on the screws will both isolate and keep them from vibrating out.
If the track has pre-drilled, countersunk holes, the OP may not have the choice of rivets. How do they work in chamfered holes?

Hi, many thanks for the quick response. So far there is nothing on the mast except the slot that took the plastic hanks. I was wondering if there was something proprietary that might fit instead. I am considering taking out the spring loaded feeder slot and feeding nuts on countersunk screws or something like that up the slot. Bearing in mind I will need to coat said SS fittings with Duralac Green or similar, it might be fiddly but worth while.
Any thoughts?
Regards
Steve

[pcmm]

Originally Posted by Wight Mistress

Hi, many thanks for the quick response. So far there is nothing on the mast except the slot that took the plastic hanks. I was wondering if there was something proprietary that might fit instead. I am considering taking out the spring loaded feeder slot and feeding nuts on countersunk screws or something like that up the slot. Bearing in mind I will need to coat said SS fittings with Duralac Green or similar, it might be fiddly but worth while.
Any thoughts?
Regards
Steve

If you have a slot, can you insert lengths of stainless steel bar and tap that instead?

[Wight Mistress]

Originally Posted by pcmm

If you have a slot, can you insert lengths of stainless steel bar and tap that instead?

That sounds like a good plan. I would have thought Harken would have had a good solution for this - I cannot be the first person to upgrade an old mast like this?
Thank you for the good idea, I will work on that. I have all the right tools and the mast is horizontal in my back garden.....
Regards
Steve

[delmarrey]

Mast slugs were always a pain for me. External metal tracks always seem to work better, but noisy. I went with the https://www.tidesmarine.com/sailtrack/ They are a bit expensive. Although, they do work very well. They don’t stand up to tropical/southern sun for very long.

I agree with pcmm. Just put in short sections of SS (or aluminum if thick enough to take 6 threads or more) drilled and tapped.

BTW you can use 3M 5200 sealer to coat the threads, and it works like Duralac and Loctite too.

[Dsanduril]

The mast slot takes “slugs”. There are a number of vendors that make tracks with slug attachments. The one I know is Antal, their HS22 track system has 7 different available slugs for round or flat mast tracks. You put the slugs in the slot, then fasten the track to the slug.

It takes a lot of slugs, their smaller boat version has a spacing of 120mm = 17 slugs for each 2m section of track. Their system is also for big track used with full-batten mains. Don’t know if they (or anyone) makes a similar system with a lighter track for normal sail slides.

Pretty sure Harken also has a slug mounting system, but not familiar with it or details.