Mast-reb-uild

[Wayne nicol]

Hi Matt,
could the bearing cars be left on the track, and then the cars just shackled/attached to the sail grommets at every rig and de rig.
how do the cars attach to the sail?
i guess if one puts in too many shackles etc- then the space from sail to mast just gets undesirably greater and greater!!

[Highlander]

Me: "Mast accidents are really very rare though."
Admiral: "Well you've had two in three years."

Woh that musta hurt one's "Skipper skills & abilities " never mind knocking u down but keeping u shacked down on the deck , maybe she just does'nt want u hurting urself , yep walking away with ur mast between yer legs before she quirp's u with something else !

J

[mastreb]

Hi Matt,
could the bearing cars be left on the track, and then the cars just shackled/attached to the sail grommets at every rig and de rig.
how do the cars attach to the sail?
i guess if one puts in too many shackles etc- then the space from sail to mast just gets undesirably greater and greater!!

The sail has sewn loops through which the cars have a bolted bobbin. It would be possible to remove the bolt with a hex key in order to leave the cars on the mast, but there's three fiddly bits to lose right at the mast, and it would take a bit of time. Best off just to go with the sliders rather than the ball-bearing cars. They have no issues and slide easily.

[Wayne nicol]

thanks Matt, good advice
cheers

[mastreb]

Wayne, I got a quote back from Chris at CC Rigging. He can make a set of Dyneema Dux stays for the MacGregor M for $900, plus shipping.

This is compared to the stock price at BWY of $200 for the stainless stays, or about 4X the price.

The advantages of dyneema are numerous:

--Stainless stays have a lifetime of about 5 years in a saltwater environment before they will have accumulated enough wear and corrosion to require replacement. The Dyneema should last at least 20, although you'll have to own that boat for that long in order to see the value. But ultimately, the 4X price will be offset by the 4X lifetime. The actual lifetime of dyneema is not known, but everyone I've spoken to about it says you can expect them to last the lifetime of the boat.

--All damage is obvious upon inspection. There's no hidden corrosion under swages, anything going wrong with the dyneema stays will be obvious as fraying or cuts.

--Dyneema stays can be easily injury rigged. Should a stay separate or be cut along it's length, you can tie two figure-8 knots in both ends and then put a few turns of smaller diameter dyneema cord between the loops and tighten to repair. This repair will be 100% of original strength and can be used until a replacement is made. You can make a similar repair at the eyes. This is a big advantage as far as I'm concerned, as a broken stay otherwise requires complete replacement. It's much simpler to carry 2' of small diameter dyneema than it is to carry replacement stainless steel stays.

--These stays are oversized to accommodate a lifetime's worth of UV damage in the sun. The outer layer of Dyneema becomes UV damaged but then acts as a protective coating for the interior. These stays are sized to ensure that they remain specified for the load throughout their life.

--Trailering is much simpler (this is the reason I got them). Instead of large wire hoops to deal with, the dyneema stays can be flaked to 2' loops and tied off with a tie. I remove the spreaders and toss mine into the cabin along with the running rigging and close the hatch for short trips, which works great. You shouldn't go below 2' loops in order to keep them from creeping.

--It's much easier to keep these stays from snagging on things while raising the mast, because they sag like ropes rather than snaking all over the cockpit and deck. I haven't had them snag on anything yet during mast raising. You do have to pay more attention to direction when putting the spreaders back on, however, as these don't "force" the correct direction the way stainless stays tend to and its less obvious which way is correct.

--The swaged eyes on sailmaker's thimbles technique used on MacGregor stays is not a best-practice for rigging. They should be straight swaged onto eyelet swage ends. The small diameter turn about the on the stainless steel dramatically reduces their load rating, and creates conditions for corrosion as that turn flexes under stress, and you can see the wire strands separating at these swages for this reason. My thimbles had all come out of the eyes as well, allowing the eyes to kink and reduce their load rating dramatically. While the dyneema stays are made using the same technique, it is a best-practice for dyneema.

--While the dyneema stays are a lot lighter than the stainless, I don't think I'd count that as a significant advantage.

--Dyneema does have one difference (I won't call it a disadvantage): When they're worked in loops (i.e., not standing under strain), they will "creep" and actually get shorter (because these stays are pre-pulled to 4000 lbs. so they're at maximum length when new. This is the opposite of stainless stays, which creep longer. On our boats it's not an issue as you can simply use the stay adjusters to accomodate. It's an advantage over stainless because if they've crept all the way to the adjuster's limit, you can pull them back out with your tow beast and a tree and start over. With stainless, once they've stretched to their limit, they're done. I have yet to see any creep at all in my stays, but they're new.

--Stay adjustment is exactly the same as with stainless.

Anyway, let me know if you'd like his contact info. Maybe we can get him to advertise here.

[seahouse]

Another benefit to Dyneema if you trailer a lot - it's less likely than the stainless to scuff and mar the gelcoat from rubbing if it happens to come into contact with it.

[mastreb]

Another benefit to Dyneema if you trailer a lot - it's less likely than the stainless to scuff and mar the gelcoat from rubbing if it happens to come into contact with it.

I've not noticed that problem, but yes, there's no way for that to happen.