Hobie 18 loose comptip

I got a little more done with this today. The peices still stuck in the mast are out now and it gave me a new approach. Instead of just building a sleeve inside the tip, I have shaved down the foam plug that was stuck in the mast , so that i can repair the cutouts and recess them so that they will smoothly fit inside the screw heads holding the tang on. I'll be repairing the base of the tip with standard poly fiberglass resin and cloth, much like I intended to build the inner sleeve. I think it will be much easier to do it like this, and probably a bit stronger too.

After the repair, I'll be following the rest of the previous plan, coating the mating surfaces and filling the recessed slots with marine JB. The hope is that the JB will surround and fill the screw heads, which are actually security heads (T-bit/star-bit), not phillips as I first thought.

Here is a pic of the peices recovered from inside the mast, which has been replaced on the comptip. It has not been cleaned, trimmed or repaired yet in this pic, just slid together.



Its still not pretty, and the bow side still needs to be completely rebuilt (fell apart as I took it out of the mast) but I think im better off than before. Weather permitting, I plan to have the repair done tomorrow, then the reinstallation the day after.

I'd like to have words with the person that did this, for doing something so silly. To me, this seems like they tried fixing a wall in a house by removing the foundation...

Kyrle

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Standard Hobie 18

I had some other stuff to do today, so I don't have enough time to do all the clean-up and repair today, probably just make sure everything is good and ready for the next opportunity to do the actual repair. In the mean time, it was brought to my attention that fiberglass resin may not react well to the foam core. My plan was to fiberglass all the pieces and the core together in one step, rather than making the fiberglass repair and then stuffing the core back in afterwards. My question is: Will the wet fiberglass react to the core or the heating due to catalyzing cause problems with the core or melt/destroy it? I figured the core might absorb some of the fiberglass resin before it cures, which I didn't see as a problem (maybe even a benefit, structurally), but a friend suggested there might be a chemical reaction, or at the very least, melting due to heat. Thoughts?

Kyrle

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Standard Hobie 18

The melting would be due to chemical incompatability (not heat). Put a drop of resin on the foam and you will know in a matter of seconds whether or not it is going to melt. Comptip is polyester resin, so you should be good - but that would be the way to confirm.

sm

I finally had the opportunity to get the fiberglass work done. I laid the (wet) fiberglass cloth around the foam plug/core, slid it into the comptip (that was interesting), then coated the cut out peices for one side with resin and put them in place. Once it dried, i thoroughly scuffed up the slotted area on the otherside, coated the remaining cut out pieces and recess, put them in place, and let it dry.

Due to the heat (I think) the fiberglass set SUPER fast, im talking 2-3 minutes, so it was a little rushed an ended up having a bit more recess in one slot and almost not enough in the other. After it dried completely and I checked the fit to the extruded mast section (which was good after some minor filing/sanding), I gave it a good sanding and filled some of the excess recess with some marine jb.

Of course, as soon as I was putting the finishing touches on the jb filling, the weather went from cloudless sunshine to looking like a hurricane quicker than the fiberglass set. I had to rush to remove the halyard and get the tip into a cluttered garage before the rain hit, since the jb takes 4 hours to set (24 to cure). Unfortunatly, I totally forgot to get pics in the chaos, so I'll have to get them before I start, next time I work on it (final re-assembly).

Also, it turns out, my friends concerns about melting the plug were not a problem. The resin didnt affect the plug at all, and it actually soaked into the plug a little, which I think will help reinforce the repair a bit.

Final updates and pics for this step to come as soon as weather permits again (I hate rain).

Kyrle

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Standard Hobie 18

I have finished the installation. It went about as expected. I coated the inside of the extruded mast section and the outside of the comptip insert section, as well as filling in the recessed areas as mentioned previously. I probably went a bit overboard, using all of the marine jb weld I had left and probably close to an ounce worth squeezed out and onto the ground. Better too much than not enough I guess. I think it will hold nicely, at least through the season, maybe longer. Though, I don't plan on testing it if I can find a replacement mast close-ish.

Really, the hardest part of this step was getting the main halyard back through the mast head, though I think some of that was my fault, the end of halyard was a bit frayed and I didn't melt it before feeding it through. Now is the even harder part, waiting... It's a beautiful day (finally), the jb has set, but I still need to wait for it to cure. Here's hoping its just as pretty tomorrow and my crew is available.

Here are some pics after the repair, but about 1/2 way through sanding the partially filled section from yesterday. All of the holes and spaces got completely filled with jb. they would have been filled with fiberglass resin with some shredded mat/cloth mixed in, but I used the last of the resin I had for the rest of the repair and it set before I could get to that part. I don't think it will be a problem though. At the stage of these pics, that whole area is rock solid and wouldn't budge by hand, and I TRIED to break it. My only concern is that normally, there would be rivets holding it in (the mast tang rivets) and the only thing holding this comptip in is the jb. Do you guys think that will be enough? or would you suggest I drill a couple/few holes and add some rivets? I was afraid of weakening everything by drilling holes, so I didn't, and don't plan to unless someone with more experience with comptips thinks its necessary. Again, this is only really meant to last the rest of the season, or until I can find a nearby mast.




I'll give another update after a few sails to let everyone know how it holds up.

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Standard Hobie 18

Between bad weather and poor timing with my crew's schedule, we FINALLY had a chance to take it out to test the repair, and I think it was a great test. The repair held perfectly. We spend most of the day going about 20mph and hit just over 28mph on a couple of good runs. Waves were moderate, but enough to strongly rock the boat a couple of times. It's hard to say based on this one day of sailing, but I think it will probably hold up really well long term. Almost certainly long enough to give me plenty of time to look for a replacement mast.

I was planning to replace asap, however at with the stress it took today, my new plan is still to find a replacement mast, but I likely wont use the replacement until the repair (or comptip) shows signs of potential trouble. I still might swap to the replacement if it is nearly perfect though, just because.

Thanks again for all the help and advice on this repair.

Kyrle

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Standard Hobie 18