Mast Base :: Catamaran Sailboats at TheBeachcats.com

Mast Base

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Edchris177

Rank: Chief

Registered: Nov 26, 2009

Last visit: Apr 10, 2024

Posts: 2524
Posted: Dec 17, 2009 - 10:34 PM

I went up to the cottage yesterday to build a rack to store the mast up near the basement ceiling, out of the way. I also took a few pictures for reference.
One thing I noticed was the previous owner was not using a proper pin, but had substituted a stainless steel bolt. The other thing was this mast has two holes, it seems a pin in either hole would retain the mast.
The parts/assembly manual only mentions one hole, & ditto for the other pictures I have seen.
Can anyone comment/shed light on why there are 2 holes?
Thanks
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Hobie 18 Magnum
Dart 15
Mystere 6.0XL Sold Was a handful solo
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Wolfman

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Registered: Jun 24, 2009

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Posted: Dec 17, 2009 - 10:51 PM

Hmm, could it be an old style mast base? Throw a caliper on the mast ball and see if it is 1.25" instead of 1.5". Otherwise someone drilled an extra hole. I've only seen one hole and one pin should be enough to trap the ball.

If it is a 1.25" mast ball you are going to have to replace the casting and the ball and dolphinstriker rod when the ball wears out (they don't make the 1.25" balls anymore). This isn't overly difficult but the new casting kit costs around $160. You can probably pick one up used though if you search for a bit.

The bolt is probably OK but the threads could mar the ball, I would use the correct stepping pin if possible.

--
Dave Bonin
1981 Nacra 5.2 "Lucile"
1986 Nacra 5.7 "Belle"
Winnipeg, Manitoba, Canada
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Edchris177

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Registered: Nov 26, 2009

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Posted: Dec 17, 2009 - 11:16 PM

I'll measure it next time up. I am going to order the pins & parts kit from Murrays.

I read you wanted a 5.7. Here is a fairly new 570 for sale, seems a reasonable price. There is also an F18 for sale in Calgary. I think you should buy one!

http://englewood-florida.olx.com/2004-nacra-570-race-catamaran-iid-57954351

http://englewood-florida.olx.com/2004-nacra-570-race-catamaran-iid-57954351

--
Hobie 18 Magnum
Dart 15
Mystere 6.0XL Sold Was a handful solo
Nacra 5.7
Nacra 5.0
Bombardier Invitation (Now officially DEAD)
Various other Dock cluttering WaterCrap
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Wolfman

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Registered: Jun 24, 2009

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Posted: Dec 17, 2009 - 11:28 PM

Ooops forgot that I already mentioned the parts kit to you.

Hmm the F18 in Calgary might be tempting! There are a few in Toronto also. I will probably perfect my sailing on the 5.2 for another year or two before making the plunge (Heck so far I've never even sailed against another cat).

D.

--
Dave Bonin
1981 Nacra 5.2 "Lucile"
1986 Nacra 5.7 "Belle"
Winnipeg, Manitoba, Canada
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Edchris177

Rank: Chief

Registered: Nov 26, 2009

Last visit: Apr 10, 2024

Posts: 2524
Posted: Dec 17, 2009 - 11:37 PM

I read a post where someone had used plastic sewer pipe to make cradles for his trailer. I have a few 8' lengths of 6", & 12" lying around. I'm going to use them to build a rack for keeping the boat just out of the water, & also when rebuilding the trailer, as the rollers they used put all the load on a couple of small points.
I needed to get the mast up off the floor, out of the way for winter storage, so I used a couple of pieces of 6" pipe to make cradles to support each end. It may not be necessary, but I also put a support mid mast. This was made out of a scrap of jatoba hardwood flooring, a wood that is twice as hard as oak, it should last longer than the boat. I used the same design as those small clips you see for tensioning tent guy lines, simple, & easy to adjust.
The spars & blades in the background are from the Invitation. I refinished the blades last summer, they are a beautiful mahogany, not competitive in todays synthetic world, but they sure look nice.
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--
Hobie 18 Magnum
Dart 15
Mystere 6.0XL Sold Was a handful solo
Nacra 5.7
Nacra 5.0
Bombardier Invitation (Now officially DEAD)
Various other Dock cluttering WaterCrap
--
Edchris177

Rank: Chief

Registered: Nov 26, 2009

Last visit: Apr 10, 2024

Posts: 2524
Posted: Dec 17, 2009 - 11:44 PM

That F18 comes with a new trailer & beach trax. Talk him down a bit, plus he's willing to deliver part way. Sounds like a pretty good deal on a fairly new boat. It also has the spinnaker. I'm amazed how much they lose in value in just a few years, then level out for the next 20.

--
Hobie 18 Magnum
Dart 15
Mystere 6.0XL Sold Was a handful solo
Nacra 5.7
Nacra 5.0
Bombardier Invitation (Now officially DEAD)
Various other Dock cluttering WaterCrap
--
Wolfman

Rank: Chief

Registered: Jun 24, 2009

Last visit: Jun 15, 2023

Posts: 1555
Posted: Dec 17, 2009 - 11:50 PM

Do you have a link to the F18?

Yeah, the are almost as bad as domestic cars.

edited by: Wolfman, Dec 17, 2009 - 10:51 PM

--
Dave Bonin
1981 Nacra 5.2 "Lucile"
1986 Nacra 5.7 "Belle"
Winnipeg, Manitoba, Canada
--
yurdle

Rank: Mate

Registered: Aug 22, 2007

Last visit: Jan 07, 2015

Posts: 742
Posted: Dec 18, 2009 - 08:27 AM

Edchris177I went up to the cottage yesterday to build a rack to store the mast up near the basement ceiling, out of the way. I also took a few pictures for reference.
One thing I noticed was the previous owner was not using a proper pin, but had substituted a stainless steel bolt. The other thing was this mast has two holes, it seems a pin in either hole would retain the mast.

I use a SS 1/4 bolt w/ a nylon locknut. It was the first thing I could find in the truck when I realized I needed something for the mast base and it's worked fine ever since.

I've never seen the two holes either. I'd tempted to ignore the extra one, but it may be there for a reason.

--
Rob
OKC
Pile of Nacra parts..
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Edchris177

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Registered: Nov 26, 2009

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Posted: Dec 18, 2009 - 09:17 AM

Thanks Yurdle, I never finished engineering, wanted to go flying, so I'm not qualified to do a total stress analysis of the mast. I'm thinking the pin does nothing, except when it comes time to step/drop the mast. All other times should be a vertical load on the ball, & even a weird gust trying to lift things should be constrained by the shrouds. After all the older systems did not incorporate a pin at all.
I'll have to have a very close look next time up, it may be the mast was the older style, & previous owner drilled it for a pin, then figured 2 pins would be twice as good!
Is the factory pin a 1/4"?

Sorry Wolfman, I didn't realize I posted the same link twice, here is the Calgary F18.

http://calgary.kijiji.ca/c-ViewAdLargeImage?AdId=170367162&back=-1&ImageIndex=1

--
Hobie 18 Magnum
Dart 15
Mystere 6.0XL Sold Was a handful solo
Nacra 5.7
Nacra 5.0
Bombardier Invitation (Now officially DEAD)
Various other Dock cluttering WaterCrap
--
P.M.

Rank: Mate

Registered: Jan 14, 2004

Last visit: Apr 21, 2024

Posts: 859
Posted: Dec 18, 2009 - 09:49 AM

Looking at the first picture, the second set of holes in the mast base was added by someone. No biggie. I would remove the rotation arm and straighten it, as it is bent. Should take all of 5 minutes in a vise.

--
Philip
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yurdle

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Registered: Aug 22, 2007

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Posted: Dec 18, 2009 - 10:16 AM

Edchris177Thanks Yurdle, I never finished engineering, wanted to go flying, so I'm not qualified to do a total stress analysis of the mast. I'm thinking the pin does nothing, except when it comes time to step/drop the mast. All other times should be a vertical load on the ball, & even a weird gust trying to lift things should be constrained by the shrouds. After all the older systems did not incorporate a pin at all.
I'll have to have a very close look next time up, it may be the mast was the older style, & previous owner drilled it for a pin, then figured 2 pins would be twice as good!
Is the factory pin a 1/4"?

Sorry Wolfman, I didn't realize I posted the same link twice, here is the Calgary F18.

http://calgary.kijiji.ca/c-ViewAdLargeImage?AdId=170367162&back=-1&ImageIndex=1

I don't know what the factory pin is. The hole fits 1/4" perfectly though so that's what I'd assume. I only use the bolt when stepping and lowering the mast. I leave it out the rest of the time.

edited by: yurdle, Dec 18, 2009 - 09:16 AM

--
Rob
OKC
Pile of Nacra parts..
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MN3

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Posted: Dec 18, 2009 - 12:26 PM

QuoteI would remove the rotation arm and straighten it, as it is bent. Should take all of 5 minutes in a vise.

Not trying to second guess you Philip but it might be bent on purpose so it fits above the downhaul turning block on the mast...

Also... that bar seems unbelievably low.. i have never seen one at the base of a mast.. oh wait, this boat is boomless, right? i guess it makes sense if it needs a better angle on the limiter line..

edited by: andrewscott, Dec 18, 2009 - 12:27 PM
nacra55

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Registered: Nov 02, 2004

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Posted: Dec 18, 2009 - 02:06 PM

Ok, I agree with Philip, it's bent, and yes a 5.7 is boomless, so why is it pointed aft and not forward?

--
Ron
Nacra F18
Reservoir Sailing Assn.
Brandon, Mississippi
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yurdle

Rank: Mate

Registered: Aug 22, 2007

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Posted: Dec 18, 2009 - 02:40 PM

Oh b/c the boom doesn't force the rotation of the mast? Good question.

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Rob
OKC
Pile of Nacra parts..
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HULLFLYER

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Registered: Aug 06, 2004

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Posted: Dec 18, 2009 - 03:18 PM

NACRA 6.0-5.8-5.7 mast rotator are all at the baseof the mast as well as a Hobie 17 and a few other boats.;
andrewscott
QuoteI would remove the rotation arm and straighten it, as it is bent. Should take all of 5 minutes in a vise.

Not trying to second guess you Philip but it might be bent on purpose so it fits above the downhaul turning block on the mast...

Also... that bar seems unbelievably low.. i have never seen one at the base of a mast.. oh wait, this boat is boomless, right? i guess it makes sense if it needs a better angle on the limiter line.. edited by: andrewscott, Dec 18, 2009 - 12:27 PM
P.M.

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Registered: Jan 14, 2004

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Posted: Dec 18, 2009 - 04:32 PM

The rotation arm should be mounted to the front of the mast/ at the base of the mast/ on Nacra boomless sails. It's to induced positive rotation on boomless sail plans.
I'll bet that the arm was bent by hitting a garage door opening or simiilar while trailering.
FYI, there are no cross over downhaul turning blocks on that mast.

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Philip
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Edchris177

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Registered: Nov 26, 2009

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Posted: Dec 20, 2009 - 10:21 AM

QuoteThe rotation arm should be mounted to the front of the mast/ at the base of the mast/ on Nacra boomless sails. It's to induced positive rotation on boomless sail plans.

FYI, there are no cross over downhaul turning blocks on that mast.

I think it is an old style base, I'll measure the ball next week. I don't see any gear that would give an 8:1 purchase, & the sail doesn't feel like it is thick enough to sustain that kind of tension. Compared to the Hobie Wave sail,(very stiff/thick) mine is almost flimsy.

It looks easy to take off & straighten. Damn, more stuff to fix Maybe I should buy that '04 in FLA or the F18 from Cowtown!
Phillip, are you saying the mounting should be rotated 180*? i.e. so that the closed end of the wishbone points towards the bows? Where do you attach the lines that come from this fitting? Anybody have a picture of their boat rigged?
The lines were undone when I picked it up. The manual seems to indicate it was an option on this boat.
Here are a couple more pics showing the mast base.
Thanks for the replies, I'm learning lots.
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--
Hobie 18 Magnum
Dart 15
Mystere 6.0XL Sold Was a handful solo
Nacra 5.7
Nacra 5.0
Bombardier Invitation (Now officially DEAD)
Various other Dock cluttering WaterCrap
--
Wolfman

Rank: Chief

Registered: Jun 24, 2009

Last visit: Jun 15, 2023

Posts: 1555
Posted: Dec 20, 2009 - 10:50 AM

Yeah, it does look like the old style mast base. If the ball is in good shape it should last quite a long time though (no reason to replace it immediately). Keep our eyes open on the want ads here, you should be able to pick up a new style one for much less money than new.

You likely shouldn't put more downhaul on that mast and sail than stock (3:1), in this case it is more used to remove the wrinkles from the sail than to depower it (no big deal really).

I have no idea how that mast rotator works!! Likely it attaches to the front beam with line in some way (normally boomless mast rotators face forward). Hopefully someone with a 5.0 or 5.7 can explain it. Worst comes to worst again, it isn't an absolute necessity, it can be sailed without rotation control.

I have found that there are 2 distinct states in sailing one of these beasts. First is actually sailing on the water, the second is fixing/tweaking the boat to make it sail better. For the first bit you will be doing more of the second than the first. I think this would be the same regardless of the boat, and likely an F18 would be worse! Although that one in Calgary is a darn good price!

edited by: Wolfman, Dec 20, 2009 - 09:53 AM

--
Dave Bonin
1981 Nacra 5.2 "Lucile"
1986 Nacra 5.7 "Belle"
Winnipeg, Manitoba, Canada
--
P.M.

Rank: Mate

Registered: Jan 14, 2004

Last visit: Apr 21, 2024

Posts: 859
Posted: Dec 21, 2009 - 12:05 AM

QuotePhillip, are you saying the mounting should be rotated 180*? i.e. so that the closed end of the wishbone points towards the bows? Where do you attach the lines that come from this fitting?

Yep. Pretty simple. Do you have a picture of your front beam? There are dozens of variations on how to rig it (very simple). Myself or others can probably help you if you will provide a picture.

As for the rotator, no need to take it off, just flip it around to the front while the mast is un-stepped.

edited by: mummp, Dec 20, 2009 - 11:08 PM

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Philip
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Edchris177

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Registered: Nov 26, 2009

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Posted: Dec 21, 2009 - 09:48 AM

Thanks for the help, good idea to just flip it, though I will probably remove it to straighten the bend. Here is the only picture I have of the front beam. It was taken from a distance, I had to blow it up quite a bit, then crop. It made the DS ball look like it is bent at the top, but in fact it is pretty much straight.
Any help you have for rigging the jib will also be appreciated. My setup doesn't quite match the old Nacra manual, & the new manual is definitely different. There is a small track on each hull, attached beside the tramp bolt rope, but I'm not sure of the line path from the clew of jib, or those cam cleats on the front beam.
Thanks again. With regards to another post I attributed to you, I could well be wrong, I read through pages of old achives looking for answers & thought you had written an old one about 1/2 hitches coming loose despite taping the snot out of them.
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--
Hobie 18 Magnum
Dart 15
Mystere 6.0XL Sold Was a handful solo
Nacra 5.7
Nacra 5.0
Bombardier Invitation (Now officially DEAD)
Various other Dock cluttering WaterCrap
--