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  #16  
Old 08-18-2008, 02:01 PM
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RHough RHough is offline
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Originally Posted by alan white View Post
There are many ways to improve the Mac. I think the most practical approach would be to balance all improvements against the rest of the systems on the boat---- meaning all running/stabding rigging (like e.g., replacing go-no go shroud adjusters with turnbuckles).
Why not add reef points to the sail?
The Mac, as delivered, is very basic. In this individual situation, it would pay to make a list of desired changes abd look at cost/benefit of each in comparison with the others.
That's why I mention simple remedies. A cunningham uses expensive blocks, and of course, a wire/rope halyard is an expense that may not make sense given so many other items screaming for attention.
I don't know if there's a winch on the cabin top already, but if not, I'd wait a while to mount one (though I think it's eventually a good idea). I'd increase the halyard sizes first and make sure the cabin top cleats are large enough.
The Macgregor design doesn't have a lot of resistance to heeling forces and so it stresses its rig much less than a lot of heavier boats. I'd have two sets of reef points installed and roller reefing for the jib if it isn't there already.
Just practical ideas to improve that particular boat.

A.
Well said
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  #17  
Old 08-19-2008, 04:21 PM
RonR RonR is offline
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Lots of sensible feedback. Thanks a whole bunch.

The shopping list is headed by 1/2" halyard and then a toss-up between t'buckles and downhaul hardware. Winches are there but never used. Roller furling jib came with the package.
The supplied Doyle came with 2 reef points. Would I then attach the downhaul to the lower cringle (proper term??) of the lower reef point, then down to a block on the cabin top. Or, should there be an independent cringle for downhauling situated above the tack?

Thanks again to all.............R
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  #18  
Old 08-19-2008, 07:36 PM
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alan white alan white is offline
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Usually, there's no grommet until the first reef position. That could be three feet, so you don't want to draw down on that. You will probably have to have a cringle sewn in (reinforced patch wi/grommet).
The question is, is the boom capable of vertical adjustment? If so, rig a downhaul with a 2:1 and use the winch to snug it. If not, have a cringle/grommet installed on the sail a few inches from the tack and rig a cunningham 2:1 and back to the winch. Any more mechanical advantage and you'll need pretty hefty (expensive) blocks to withstand both tackle and winch (which is likely about 7:1 alone.) In other words, you'd have maybe 14:1 hauling down that sail, so where you've got a winch (3"?), go easy on it!
The idea with the cunningham would be to have a small fold along the boom, not a baggy area up to the first reef.
Personally, I think why not just use the halyard to adjust? Or at least, any downhaul could be pre-adjusted and not even need a line back to the cockpit.
Just a cleat on the aft face of the mast (they make ones that screw into a slug that fits in the sail slot).
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  #19  
Old 08-19-2008, 09:04 PM
Paul B Paul B is offline
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Originally Posted by alan white View Post
Usually, there's no grommet until the first reef position. That could be three feet, so you don't want to draw down on that. You will probably have to have a cringle sewn in (reinforced patch wi/grommet).
The question is, is the boom capable of vertical adjustment? If so, rig a downhaul with a 2:1 and use the winch to snug it. If not, have a cringle/grommet installed on the sail a few inches from the tack and rig a cunningham 2:1 and back to the winch. Any more mechanical advantage and you'll need pretty hefty (expensive) blocks to withstand both tackle and winch (which is likely about 7:1 alone.) In other words, you'd have maybe 14:1 hauling down that sail, so where you've got a winch (3"?), go easy on it!
The idea with the cunningham would be to have a small fold along the boom, not a baggy area up to the first reef.
Personally, I think why not just use the halyard to adjust? Or at least, any downhaul could be pre-adjusted and not even need a line back to the cockpit.
Just a cleat on the aft face of the mast (they make ones that screw into a slug that fits in the sail slot).
Are you kidding?

We're talking about a Mac 26. Using a 1/2" halyard? Madness. If you use anything more than 3/8" it is overkill, and you would only use that because it is easier on the hands than something smaller.

Using a winch for the cunningham? On that boat a simple 3:1 using Harken Micro Blocks (or equivalent) is enough. My 28 foot racing boat with a mainsail approx. 1.5x the size of the Mac's uses a 4:1 cunningham and it is a 2 finger operation. Don't cunningham from the reef point, use a dedicated ring for this applicatioon.

Of course I also use a halyard lock to keep the main up, so no worries about any halyard stretch (not to mention halving the mast compression due to main halyard load). It is not a bad idea.

You should not need a winch to raise halyards or adjust luff tensions on that little boat.
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  #20  
Old 08-19-2008, 11:55 PM
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Originally Posted by Paul B View Post
Are you kidding?

We're talking about a Mac 26. Using a 1/2" halyard? Madness. If you use anything more than 3/8" it is overkill, and you would only use that because it is easier on the hands than something smaller.

*Recommended rather than go to wire halyards or Spectra if wanting to reduce stretch.

Using a winch for the cunningham? On that boat a simple 3:1 using Harken Micro Blocks (or equivalent) is enough.

* The winch is already there, so I mentioned only 2:1 on the cunningham, and go easy if winching. Not necessary, just handy.

My 28 foot racing boat with a mainsail approx. 1.5x the size of the Mac's uses a 4:1 cunningham and it is a 2 finger operation. Don't cunningham from the reef point, use a dedicated ring for this applicatioon.

* So I said.

Of course I also use a halyard lock to keep the main up, so no worries about any halyard stretch (not to mention halving the mast compression due to main halyard load). It is not a bad idea.

* No, it's not a bad idea, but more expense than a lower stretch rope. A 1/2" rope will stretch about 1/2 as much as 3/8. But I don't think the mast compression from halyards is a problem anyway on that boat.

You should not need a winch to raise halyards or adjust luff tensions on that little boat.
* No, I agree it's not really necessary. Just handy.
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  #21  
Old 08-20-2008, 05:56 PM
RonR RonR is offline
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You folks are making this a real education for me, also lots of others too, I hope.

Now, just to add something else to the equation, how about this?

Recently I added a 6:1 arrangement for the vang which comes back into the cockpit. It works a treat. It ends knotted to a bale at the bottom of the mast. I've been trying to figure out how, if instead of it ending tied at the foot of the mast, I would bring it up to the cringle (if I have one) then back down again to the mast foot, would that one control 'kill two birds with one stone' so to speak?


Is it likely for both to be needing adjustment similarly for the same circumstances ..??
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  #22  
Old 08-20-2008, 06:41 PM
Paul B Paul B is offline
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Originally Posted by RonR View Post
You folks are making this a real education for me, also lots of others too, I hope.

Now, just to add something else to the equation, how about this?

Recently I added a 6:1 arrangement for the vang which comes back into the cockpit. It works a treat. It ends knotted to a bale at the bottom of the mast. I've been trying to figure out how, if instead of it ending tied at the foot of the mast, I would bring it up to the cringle (if I have one) then back down again to the mast foot, would that one control 'kill two birds with one stone' so to speak?


Is it likely for both to be needing adjustment similarly for the same circumstances ..??

No, the two items are at times going in the opposite direction.

For example, unless you are vang sheeting you generally only need the vang with the slack taken out of it while going upwind (watch the video of things like the past couple of America's Cup series to see the vang hanging loosely upwind). But upwind you'll want to adjust the cunningham to position the draft of the main (I'm assuming you have a dacron mainsail).

Downwind you need the vang on to keep the boom from lifting when the sheet is eased, but you'll want to dump the cunningham or the draft will be too far forward. By the way, 6:1 sounds like way overkill for a vang on that boat. A 4:1 would have been sufficient.

Please don't spend (waste) your money on some ridiculously oversized halyard to solve a "problem". Better to take that amount of money and get a sailing lesson from someone who is really good.
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