I recently bought an old Nacra 5.2 for parts (to improve my new-to-me 1977 5.2), and swapped its mast (with its extra blocks, cleats, and wishbone) for mine (which had the old anti-rotate ROD, fewer blocks and cleats). Both boats have probably only been sailed on freshwater lakes.

After removing the old-style base casting from my "new" mast, I took a peek inside and saw significant rust stains on the wishbone's through-bolt anti-compression sleeve. Seeking to prevent further corrosion, I tried to remove the bolt and sleeve with no luck. I've searched the forums but couldn't find anything directly addressing this issue, which I assume is common.

I did find another beachcats post re: removing a corroded dolphin striker rod/sleeve from the crossbeam, but I think the mast situation differs because (I'm guessing) neither mast hole will allow the sleeve to pass through.

Here’s my plan. Have I overlooked something or is there an easier way? I assume you experienced folks have been through this a time or two.
1. Cut or grind off through-bolt head.
2. From cut end, remove outer washer, wishbone (may require some slight bending), inner washer.
3. Grip cut end with vice-grips and tighten nut to begin pulling the through-bolt through compression sleeve. If vice grips aren’t sufficient, grind flats on bolt end and hold with a wrench.
4. If bolt can be freed from compression sleeve, pull it all the way through and remove sleeve. If bolt can be pulled completely inside the sleeve but not all the way through, do so and then cut nut end of bolt flush with outside of mast and try working the remaining sleeve/bolt out through bottom of mast.
5. If bolt CAN’T be freed from sleeve enough to pull it inside the mast, skip Step 3 and remove nut, washers and wishbone from other end of bolt.
6. Gripping threaded end of bolt with vice-grips, use hack saw to cut head end of bolt flush with outside of mast.
7. Fix hacksaw blade to a stick and, while gripping nut end of bolt, cut through middle of sleeve/bolt.
8. Remove head half of bolt/sleeve, then nut half of bolt/sleeve.

Any experience/advice you wish to share would be greatly appreciated. Having learned lots of lessons the hard way, I am hoping to take the easy way (learning from others before I end up in a deep hole) on this one.

Many thanks!

Peter

Laser (sold years ago)
P-16 (sailed a few years, hulls delaminated, sold for parts)
Nacra 5.2

Try some corrosion-x spray and spray it several times over the course of a couple days

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Captain Chris Holley
Fulshear, TX
'87 Prindle 19 "¡Hijole!"
'74 sunfish "1fish"
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I have found PB Blaster to be the shizzle for freeing rusted fasteners.

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'82 Super Cat 15
Hull #315
Virginia
Previously owned: '70 H14, '79 H16, '68 Sailmaster 26, '85 H14T
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I've used lot of different products over the years PB Blaster is good but Kroil works the best by far soak it let it set a couple days it's amazing also you might try a little heat on the sleeve if you can w/o damaging anything around it ? If it wont move after you cut the head off before you try cutting it in to try drilling the center out from both sides to drop it in ? if nothing else you will have less to cut with the hacksaw blade on stick

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H14
H16
H18
H18
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Thank you all for your replies. I've just assumed that the bolt and sleeve were permanently corroded together (as is common with aluminum seat posts that get permanently frozen inside steel bicycle frames), but Corrosion-X, PB Blaster and Kroil are all worth a try.

I also like the idea of drilling out the ends to shorten it enough to drop free. Much easier than the hacksaw blade on a stick!

Thanks all!

Peter

My only experience is with the Hobie rotator bar setup, but I assume the NACRA system is similar, if not identical.

In my experience dealing with corroded parts like this, especially if the boat has been sailed in salt water, you will be wasting your time fussing around with any type of penetrating oil. The compression sleeve is a tight fit and runs nearly the entire length of the bolt. The rotator bolt on a 40 year old boat is likely to have so much corrosion that the boot and sleeve are virtually fused together with no place for the penetrating oil to penetrate.

I wouldn’t waste time with oil or trying to drill anything out. I would just cut the bolt off and be done with it.

sm

It's a freshwater boat, however, based on what I can see of the outside of the sleeve there's been significant corrosion. I'm not pressed for time, so I'll give the penetrating oils a try but will keep your cautions in mind. What you describe (tight fit along entire length, many years of wetness) sounds sadly similar to my old bike frame's seat post. My hopes died a slow death on that one.

I see now that some folks make 18" sawzall blades, if I can lay my hands on one that fits my saw. Sure would beat the blade-on-a-stick arrangement.

Thanks for your advice!

I saw this a few day ago. I knew I had a little surface corrosion between my mast and wishbone. The bolt spun freely though so I didn’t have anything stuck. I got some one inch nylon washers and stainless fender washers and put them between the mast and wishbone on both sides after cleaning up the surface. Should last a long time now. Also antisieze on bolt.

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Tim
Collierville (Memphis), TN
Supercat 15--sold :(
Hobie monocat--given
Vanguard 15--traded for...
Nacra 4.5--sold
Nacra 5.7
Hobie 14–sold to make room for...
Supercat 17–sold
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Thanks for your note. I'm not sure that the bolt spinning freely would indicate that there's nothing stuck. Were you able to withdraw the bolt from the sleeve?

Once I get the old bolt/sleeve out of there, I plan to thoroughly coat the entire length of the new bolt with an anti-corrosive agent like Tef-Gel, then slide it into a new sleeve inside the mast, with nylon washers placed between the outside of the mast and the stainless washers that would be under the head and the nut on the bolt. Now that I think about it a bit more, I think I'll also need to have a short nylon sleeve to keep a space between the shaft of the bolt and the places where it enters and leaves the mast/sleeve. The idea is to eliminate the possibility of any electrical-conducting contact between dissimilar metals, i.e., between the stainless bolt and the aluminum mast and sleeve. Using a stainless sleeve might be an improvement, if one could keep it from contacting the inside of the mast with a nylon washer.

If anyone has more experience with this, please chime in.

Peter

My bolt came right out. I just cleaned it all up good and put it back.

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Tim
Collierville (Memphis), TN
Supercat 15--sold :(
Hobie monocat--given
Vanguard 15--traded for...
Nacra 4.5--sold
Nacra 5.7
Hobie 14–sold to make room for...
Supercat 17–sold
--

I’m pretty sure if you can rotate the bolt it will tap out easily. If you do get the bolt out I bet you could get the sleeve cleaned up really well. Maybe use a gun barrel brush or some such to clean all the yuck out.



Edited by tnell on Sep 26, 2018 - 11:30 PM.

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Tim
Collierville (Memphis), TN
Supercat 15--sold :(
Hobie monocat--given
Vanguard 15--traded for...
Nacra 4.5--sold
Nacra 5.7
Hobie 14–sold to make room for...
Supercat 17–sold
--