Hello,

How do the mast on the nacra 5.7 and 5.8 differ?

I have a 5.8 mast on my 5.7 boat. Don't want it to fall off the ball.
I noticed a lot of shedding of the white ball and the ball seems to spin when rotating the mast.

I hope I can use the 5.7 sail on the 5.8 mast.
Anyone with experience know?

How old is the ball?
Old ones, left in a high UV environment degrade. Buy a new one.
Secondly, look at the cup on the mast base.
Is there a sharp edge, or burr, that is cutting into the mast ball?
Don’t worry about the ball turning. Both my 5.0 & 5.7 do that. As the mast rotates left, it unscrews the ball 1/4 turn, when it rotates the other way, it turns the ball back down.
There may be other issues, but if your rigging is tight, the mast cannot fall off the ball

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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
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Ok Thanks, I am not sure the age of the ball I just got the boat.
Do you know if the 5.7 sail work on a 5.8 mast?

Does a new ball just screw on to the bolt?

The ball just screws on by hand. I was experiencing ball spin on my Nacra 5.2. Last week I polished the mast base. I took 120grit paper and taped it over a phillips screwdriver handle and chucked it up in a drill. I followed that with 220 grit. Now it is smooth and doesn't spin the ball.

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FYC, Nacra 5.2 "Chris's Flyer" & Nacra Playcat & Farrier Tramp
Previously owned: Trac 14, H14, H16, H18, N5.0, G-cat 5.0
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Not sure if it's a good idea to let the ball rotate. A lot of focused pressure on those threads and it certainly wasn't designed for that. Mine started doing it when the ball started to flatten out at the top after a lot of use. I got a new one and hand tightened it as much as possible and then used a channel lock pliers and gave it an extra 1/8th inch, no more!

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Bill Townsend
G-Cat 5.0
Sarasota
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no experts on these boats?
also anyone how the 5.8 and 5.7 mast differ?

Recommend you contact BRNwatersport.com. They sell parts for all these older boats. Im sure they can give you a correct answer.

found this at below link for Nacra measurement guide
5.8 mast length = 9156mm
5.7/5.5 mast length = 8858mm

https://ausna.com.au/wp-content/uploads/2019/03/2015-NACRA-Measurement-Guide.pdf

I have a nacra 5.7 mast for sale, also a tramp and a rear crossbar.
Located in Delray Beach Fl 33444

Just add a ca 30cm wire strap between head and halyard ring to compensate for the difference in length. Another more radical solution is to cut the mast top 30cm to correct length.

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Brgds
Lars

Frankentri 5.8/5.5/Inter20
Aerow trimaran foiler

https://www.facebook.com/groups/1192604934176635
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So it the 5.8 mast 30 cm longer than the 5.0?

According to the Australian paper above difference is 30cm. To make the 5.8 mast closer to the 5.7 you should cut 20cm from the base and 10cm from the top, to get the hounds at the correct height.

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Brgds
Lars

Frankentri 5.8/5.5/Inter20
Aerow trimaran foiler

https://www.facebook.com/groups/1192604934176635
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