'82 Mac25 fiberglass crackling sounds...

[Mac25]

Regarding my (new to me) '82 Mac25: When standing on the port cockpit bench, or when walking in front of the mast, I feel a little flex under my foot, and hear a crispy-crunchy-crackle in those areas of unsupported fiberglass. Should I be concerned? The '78 Venture 25 I sailed on last week shows no such flex or sounds in these same areas.

Also, I found a great deal on bulk generic 3/8" Double Braid Polyester Rope. Can I use this to replace ALL of my sheets and halyards, or is 5/16 really better for the stock pulleys and cleats in any of these applications? Given the very long length I must purchase to get this great price, how wrong would it be to also use this as docking and anchor lines?

Thanks,
Mac25

[K9Kampers]

...hear a crispy-crunchy-crackle in those areas of unsupported fiberglass...

I hear the same on my , but know it's from my knees, not the boat!!

[Ixneigh]

These boats have cored areas in the decks. My 73 has ply core in the foredeck and cockpit seats. The core in your boat may be damaged or rotted. Make sure the area is sealed, such as fittings or screws nearby and forget it. The older boats are not worth the expense to extensively repair unless the boat means more then just a cheap way to get out on the water. You can use epoxy to inject and fix very small areas such is under the mast.
The rope is strong enough for rigging purposes but too small to anchor with. It will be difficult to pull up.

Ixniegh

[Crikey]

I agree with Ixneighs epoxy injection fix. It's fairly tricky to do right and if extensive, may require finding or making screw holes in the affected areas to put enough epoxy in place.
Besides proper choice of material and mixing catalyzer ratio, you'll need to have someone inside the boat, ready to prevent any escaping resin ruining other parts of the interior. Remember, a warm deck or void will completely alter the setting time of a mixture you're trying to finesse into a small space. You could also count on the tool(s) you're try to do this with, as expendable!
Ross

[RobertB]

If the wood core is soft - not rotted to the point of powder, there are epoxy products formulated for reconstituting rotten wood. These are generally a lighter consistancy (even some are water based). If you can figure out how to apply without the epoxy running everywhere, you may then make a second application of thickened epoxy or even urethane foam (suggest the non-expanding type) to fill the voids. I used the expanding type to back up a panel repair on an interior door (in the house) and the dang stuff caused a bulge in the door.

[MacNCheese]

Regarding my (new to me) '82 Mac25: When standing on the port cockpit bench, or when walking in front of the mast, I feel a little flex under my foot, and hear a crispy-crunchy-crackle in those areas of unsupported fiberglass. Should I be concerned? The '78 Venture 25 I sailed on last week shows no such flex or sounds in these same areas.
Mac25

My 88 Mac26D has the same crispy crunchy-crackle noise as yours when i walk in the cockpit area. Two cracks formed on either side in the same place. I'm wondering if the Ventures were made better with thicker fiberglass because they were hand laid. In the 80's I've been told they started using computers and spreading the fiberglass more evenly but thinner to save money. I'm not certain of this, but it would explain why our 80's models are falling apart faster than the 70's models. In 10 years, we'll see how well the newer and hold up and if they were made as cheaply.

The fiberglass on my 1976 Pearson26 was still strong with no cracks and I didn't hear any creaks when I walked in the cockpit (It was sold earlier this year). As much as I like my MacGregor, I've concluded that they are not well made and will not last as long as most other brands.

You can see where the crack is in the corner of the cockpit, and the opposite side developed a crack in the same exact spot:

[Mac25]

Thanks guys.

I had no idea there were wood cores in those places. Makes sense now, and I now see how the previous owner failed to properly bed the through-deck bolts he drilled. If I opt to do this repair, I will use CPES and follow these well-written instructions:
http://www.boatbuilding.net/article.pl? ... ode=thread

It seems that the most difficult part would be getting ALL moisture out before applying the CPES. I cant imagine how many holes would have to be drilled to allow those cores to dry entirely.... Hmm, maybe a vaccum pump sealed onto a centrally-drilled hole would speed things along....

Mac25

[snotnosetommy]

I'm under the impression that acetone has drying properties applicable to a plywood core. If you have to drill to inject epoxy, perhaps you can inject a little acetone first.
My M25 doesn't do much crackling, but I have often wondered what a good breaking wave would do to her hull.
Good luck with your repairs.

[Catigale]

That's a gel coat crack, not a FG crack, IMHO.

Big difference wrt structural issues....gel coat cracks are basically cosmetic only.

[MacNCheese]

That's a gel coat crack, not a FG crack, IMHO.

Big difference wrt structural issues....gel coat cracks are basically cosmetic only.

Thank you for that information, a big relief to know that my cracks aren't too serious.

[Catigale]

live love sail

[Mac25]

Hey guys,

I was back on my '82 Mac 25 boat today. To be clear: there is FLEX when I stand on the port cockpit bench. There is FLEX when I walk on the foredeck in front of the mast. Hard to imagine there was ever any wood there.
Can you tell me FOR SURE which areas have wood core, and which don't?

Thanks,
Mac25

[tubeydude]

On mine there is a crunching, rubbing sound when I move around the cockpit. If you look under the cockpit floor the rear liner bulkhead is right there. When you stand on the cockpit floor it flexes a bit and touches the bulkhead. As it is not very strong or attached to the floor the two meet. When this happens they slide past each other making the cracking sound. I was going to try to put something there (like some high density foam to quiet the noise, but have no done it yet. I guess that point could also be glassed together. I would not bolt them together with bracketry as this would require holes in the cockpit floor.

[snotnosetommy]

On my M25, the cabin roof and the foredeck are cored with plywood (about 7/16" as nearly as I can tell), and do not flex or crackle. I do not think there is plywood core anywhere else.
Nearly all fiberglass boats get gelcoat surface (spider) cracks. Not the same thing.
I occasionally here a slight crackle from the cockpit floor or the benches, which are definitely not cored. Not movement, not loud and not regularly. It never bothered me, but if it did, the idea of sticking a piece of foam between the bottom of the floor and the hull seems like a good idea.
The benches could be reinforced easily by gluing a slab of plywood underneath with epoxy.

Heck, there's a lot of flex in these boats, which may not be a real bad thing for all I know.
The first time I jacked my boat up off the trailer, I put the rear sawhorse too far forward and the weight of the boat squished the bottom of the hull upward. Moved the horse rearward, popped right back out.
Hope this helps.