OK, maube someone can help me with this,

I'm repairing cracks that happened from stress on the hulls of my TheMightyHobie18 at the forward crossbars (under the lip of the deck).

I've opened the cracks about 1/2" and grinded off the gelcoat about 1 1/2" from the cracks. I need to repair the holes (which are about 5" long) and reinforce the area to make it stronger. Can anyone give me a list of materials needed for the repair including product names? I will be shopping for these at West Marine. I have already done the prep work so all I need to do at this point is buy the repair materials. Also any repair tips would be greatly appreciated.


Many thanks!

I can't be of much help but with regards to the repair but for the raw materials...look here too:

Aircraft Spruce

What year is your boat and how long are the cracks?

Hi, Mike

It is a 1985 Hobie 18. I just measured the cracks, and they are about 6" long to each side of the cuped out space where the forward crossbar attaches. I have opened these cracks up to about 1/2" approx. They are below the lip of the deck and happen right at the spot where hull meets deck (but on the hull).

just moving my post back to the top. heh heh

West System

High Density Filler

patience.

For making the structural repair I would use 5 or 6 oz cloth with epoxy resin. I think the only epoxy they sell is West System. Sand a taper around the crack so that the original material is paper thin at the opening and tapered back about an inch around the cracks. Start with a piece of cloth just slightly larger than the opening and lay progressively larger pieces on cloth on. The idea is to match the the taper with the progressively larger pieces of cloth so that the repair is not raised above or sunken below the original surface. In reality it never comes out perfect so you will have to sand off high spots and fill the low spots. I believe the filler from West Systems is called "Micro Light". It mixes with epoxy to make a paste that is basically "boat bondo".

Why not repair with carbon? Carbon fibre is 29X stronger than fibreglass?

Websites for carbon materials:

http://www.fibreglast.com/

http://www.acp-composites.com/

What I did a long time ago was epoxy 1" Carbon tape on the underside of the lip
all around the boat, since it was basically cracking everwhere.
(If you question the legality of this the 1989 Worlds TheMightyHobie18's where carbon reinforced.)

While you are at it you might as well do the rear beam area next,
as it will start to crack once you stiffen up the front.

In addition, As I recall, I took old aluminum rudder pins and West System'ed them
under the lip at all four beam beam attachment points. (Aluminum is 10X fibreglass?)
At first I only did this at the main beam, but then the ream beam area cracked
and the boat would mysteriously fill up with water.

Look for Hobie 18 "anchor plates" These stainless steel plates strengthen the cross bar to deck areas. My 1989 has them on each side of the front crossbar and at the point where the shrouds are anchored. I am adding some to the rear cross bar because I intend on adding a spinnaker and/or wings some day.

In the many posts on this subject- I turned the H18s on their sides put glass cloth and epoxy on the INSIDE thru the porthole. Very messy to get it flat and unfolded against the crossbar mountings, but will be a LONG time til it cracks again.

Thanks guys,

I've got the West system Epoxy, Slow hardner, 6 oz. glass, High density filler, rubber gloves and assorted tools, (and patience) and am ready for the repair this weekend.

I'll keep you posted