First post, seems like a great forum. Hobie-specific question so could have posted on the Hobie forum but thought I'd use the excuse to sign up here.

I have a Hobie 18, hull # CCMC0914D685, Coleman logo, which I think makes it a 1985 boat (will have to pull out the paperwork to confirm I suppose), but it has white glue instead of red glue inside the hulls. From reading on the forums all '84-'85 boats seem to be reported as red glue, but this one may be an anomaly. I'm guessing it's still a lighter weight 18, same as the red glue boats, and could possibly suffer from the same weakness in the hull design. I've been reading up on the hull failure and reinforcement, and plan to do the plates at the front beam this summer and maybe the interior glass work this winter (it only has a narrow patch on the inside). But we sail on small inland lakes in Colorado (our big local lake is 1.5 miles x 1.5 miles) and don't have wings so don't feel we put too much stress on the boat.

Any insights would be appreciated.

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Matt Miller in Colorado
'82 H14 Turbo #38674 Red/Gold
'85 H18 #13222 Nationals White (Prism)
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I have an 18 made in Feb of 85, and another in Aug of 86. Both have Red Glue and both had gel coat cracking around the beam mounting points. Since yours was April of 85 I think it's safe to say your's is going to be the same construction. I'd do the reinforcement plates on the front beam regardless of the color of glue. I think the glue was just an indicator of a general era that the hulls were built with less reinforcement.

I'd do the plates and reinforcement patch for sure just to be safe. Between the plates and fiberglass it's like a 100 buck project. I personally don't think the patch is necessary after putting the plates on but it's so simple to just slap some cloth in there why not.

According to the serial number, your boat is a 1985 model year manufactured in 1986 (doesn't make a lot of sense, but possible I suppose). It would be hard to say the construction for sure (maybe Matt Miller would know). The "red glue" boats are considered to be from the era where Hobie reduced the amount of glass and made other changes to the manufacturing process for the 18. The change only lasted for a short period, and your boat was made during the transition period. That time was also a very high production rate for the 18s (and Hobies in general). There was a lot going on and a lot of manufacturing, so I'm sure possible your boat could have been built with a different color glue.

At this point, the more important thing is to give your boat a good inspection. I have a 1985 H18 (red glue) and it cracked completely through under the flanges where the crossbars attach. Check this area closely. If this area is in good shape (gelcoat cracks are OK, cracks through the glass are not) then likely you do not need to worry about adding the reinforcement patch - the boat has lasted 30 years so far. I would just add the upgraded stainless plates. Also check the hulls really well for soft or excessively flexible areas.

If the hull flange is cracked or you suspect there may be structural issues, then adding the patch is probably appropriate. To add the patch properly is a lot of work. It's best to disassemble the hulls from the crossbars to do the job right. You'll need to grind away the excess glue from the hull joint before laminating the glass and this is challenging because of the location and limited access. It takes a lot of sanding and prep work to do the job well.

sm

Thanks guys! This boat's a peach, some minor nicks in the dagger boards and trunks, a couple chips on the comptip, I think generally it's led an easy life. We bought it in 01 or 02 or so and it hasn't touched water in 9 years now, which I'm changing this summer. Looked and didn't see any cracks on the hulls or near the beams, no soft spots at all. Just going to run it and enjoy it, but still add the plates for a little assurance. Just thought it was funny that I've seen mentioned black glue and red glue but no white glue, and this has white glue.

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Matt Miller in Colorado
'82 H14 Turbo #38674 Red/Gold
'85 H18 #13222 Nationals White (Prism)
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Quote

To add the patch properly is a lot of work. It's best to disassemble the hulls from the crossbars to do the job right. You'll need to grind away the excess glue from the hull joint before laminating the glass and this is challenging because of the location and limited access. It takes a lot of sanding and prep work to do the job well.

+1
I just finished this on my 'late '84. You cannot just slap a piece of cloth on. The underside of the beam results in some complex curves, it's a bit of work to get the cloth to lay properly on some of the transitions.
As Dogboy says, it is WAY easier to separate the hulls. I rigged up some blocks on the trailer, so I could set them at the most favourable angle, gravity then helps with the cloth, & making the task of filleting the deck/hull joint easier.
I didn't grind the blobs of glue. I found it is quite brittle,(black glue), & by using a 1/2" carpenter chisel, & a small hammer, it neatly broke away in large chunks. I then poured thickened epoxy,)ketchup like) onto the joint, letting gravity mold it. I needed a small bit of cloth placed strategically to prevent it flowing down the ramp made by the rounded beam mount.
Do yourself another favour, remove the hatch frames, that extra inch makes a world of difference. I got rid of the old style Hobie hatches, with the "yank out" covers, & replaced with screw ins.

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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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