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PostPosted: Fri Jun 21, 2013 12:21 pm 
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Last year I broke my mast receiver and mast. I got a new crossbar with the reinforced receiver plate and a new mast under warranty. When installing these I went ahead and replaced the bottom V brace screw with the new stronger one while I was at it. When reassembling I tightened the V brace assembly as much as I dared, just to the point I began to see the bottom of the hull expand a bit below the V brace. Up top I put a few wraps of electrical tape on the crossbar under the clamps in the hopes that they would hold tighter.

I am noticing that I am still getting some side to side movement of the crossbar inside the clamps. I can tell because the tape I installed has gotten torn up from the movement. I haven't noticed any negative effects and I do not have the "clunking" noise during tacks I had before the failure. Does anyone else have this crossbar play and is it something I need to address?


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PostPosted: Fri Jun 21, 2013 1:15 pm 
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Navigate over to this thread -- http://www.hobiecat.com/forums/viewtopic.php?f=75&t=33638&hilit=crossbar+failure

The tape is a great insulator but lousy for grip as it heats, gets wet and degrades. Better to just goop up the joint, or try some of the ideas in the larger thread. The best Hobie minds have weighed in on this.


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PostPosted: Fri Jun 21, 2013 1:21 pm 
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Thanks for the prompt reply. I'll check out the thread you linked. I had searched but didn't find that one.


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PostPosted: Fri Jun 21, 2013 1:53 pm 
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NOHUHU wrote:
The tape is a great insulator but lousy for grip as it heats, gets wet and degrades. Better to just goop up the joint, or try some of the ideas in the larger thread. The best Hobie minds have weighed in on this.


I just reviewed the other thread. No idea how I missed that. I've got a sealant called "though the roof" that I have no doubt would solidify the crossbar and clamps into one unit. As was mentioned in the other thread this would eliminate the serviceability forever. My crossbar movement seems to be no more than 1/4" and my cleats are mounted on either side of the starboard clamp. I think I'll just continue to monitor the situation instead of doing anything drastic.


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PostPosted: Fri Jun 21, 2013 2:30 pm 
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1/4" is a lot. If that's seen on both sides of a clamp, it's worse.

"Goop" is easily removed. It may add some grip and tension to the joints.

I still like the simplicity of pinning (screwing) the crossbar to the clamp (or strapping the clamps to the bar). You just can't let any screw threads protrude into the crossbar tube.

All your Aka attachment points should be tightened and your V-brace calibrated before doing this.


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PostPosted: Fri Jun 21, 2013 3:28 pm 
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I haven't looked at it very closely but it's got to be a solid 1/8" each way. I really don't think any sealants with elasticity would help much. Pinning like you suggest may be the best way to go for a solid fix. I need to start with the adjustment of the v brace assembly to make sure that's correct. Is there a spec or procedure for that?


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PostPosted: Fri Jun 21, 2013 4:51 pm 
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My technique

Loosen the top 2 hull nuts and compress the turnbuckles until it slacks on both sides. Expand them evenly till you have slight positive pressure in the hull. Lock them in.

If your mast's furling ring doesn't clear the bearing plate, try reversing the turnbuckles, with everything tight, until it does.


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PostPosted: Fri Jun 21, 2013 5:32 pm 
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Thanks for the info. That seems like pretty much what I did. I may be able to go a little tighter. As I recall I have plenty of space between the furling ring and the receiver plate. It looks to me that the configuration of the v brace tension would only have a limited effect on preventing the crossbar slippage. It just seems like the configuration doesn't provide a great deal of stability to prevent side to side movement of the crossbar. Or am I missing something?


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PostPosted: Sat Jun 22, 2013 1:02 am 
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You're right. It's there to brace the mast and protect the hull.

The clamps "hold" the bar against many directional Aka forces, but it's not a solid connection as with the older pinned crossbars. Those were bolted to the hull.

It's been suggested that side slip (clunking) may lead to added mast stresses and to the cracking and failure of the mast bearing plate, masts and possibly other components.

All that may not be the case, but still, that clunking sound is never a good omen on the water.


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PostPosted: Sat Jun 22, 2013 4:38 pm 
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At least I no longer have the clunk.


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PostPosted: Fri Jun 28, 2013 9:51 am 
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There should be two bolts in the center of the crossbar that connect it to the mast receiver. On the TI, there is a spacer block in there and the AI crossbar bolts right onto the mast receiver. This helps prevent slipping. The blocks on the TI may wear overtime and need to be replaced if the holes are elongated. The spacer on the TI is #88991271.

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PostPosted: Sun Jun 30, 2013 3:52 am 
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Hobie sent me a new spacer block with the warranty claim, which I installed. IMO the real issue here is the crossbar clamps are plastic and cannot provide enough force to hold the bar firmly.


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PostPosted: Sun Sep 08, 2013 3:44 am 
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I have copied my post to the other thread (as above) on this subject as this is the more recent one.
One of the proposed fixes is to glue the crossbar with Loctite blue which is semi-permanent.
It is spring here and I have replaced my old failing crossbar with the new through-welded one that Hobie sent promptly via my excellent dealer, Binks Marine. I checked adjusted and tightened every thing, but did not apply Loctite to the surface of the crossbar where the clamps go for a couple of reasons. Firstly, I wanted to see how the new part would perform in standard trim, and secondly, I could not get Loctite from the local (large) hardware store, bought a generic copy, and then read that it was not recommended for use on plastics. Can Loctite be safely used on plastic?
The bar unfortunately still slips back and forth quite freely, although it is now limited by the blocks mounted either side.
I am back to where I started with this. No-one who has replaced the bar and or the spacer block under the mast collar has said that the lateral slippage has stopped. It has only been reduced by the return to siting the Harken blocks either side of the starboard clamp, and I don't believe a plastic saddle clamp will ever be able to achieve enough friction to withstand the enormous leverage that a loaded mast would exert. There is only one way to fix this - pin or screw the crossbar to the hull though the crossbar clamp base.
I am about to risk my warranty by doing it, but the slop in this structure is driving me nuts.
Anyone else out there taken drastic measures?


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PostPosted: Sun Sep 08, 2013 6:22 am 
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I personally wouldn't risk degrading the plastic clamps using loctite and IMO it wouldn't prevent the slipping anyway. I am still getting a fair amount of movement but it is no longer making any noise so I am inclined to just let it slide.


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PostPosted: Sun Sep 08, 2013 6:31 am 
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Be VERY careful using Loctite on plastic, I have seen some plastic become as brittle as glass due to the chemical reaction with Loctite.

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