Hull flex question Hunter 23 1986

[imp6]

My first boat and first post hope it’s in the right location.

this is a hunter 23, 86’ I believe.
It has the Kenyon boom, double pin flat mast attachment(not the triangle one) point.

four areas on the hill above the waterline have significant flex paired with some crackling when pushed. They are notably the areas where there is no reinforcement framing on the inside of the boat. The two aft sections on between the main Framing for companionway and back of boat. And the front v berth between the midway framing and nose of boat.

it doesn’t seem to me there’s any core here to really be rotted and I’m wondering if this flex is acceptable. Included video to show. If you think it’s out of ordinary or unacceptable what steps would you take to fix. Thanks everyone!

 

[Ralph Johnstone]

@Crazy Dave Condon

Your opinion ?

 

[shemandr]

Seems like a lot of flex to me. But I'm no CDC.

 

[Rich 35.5]

My 23.5 did the same in the bow area. I had it for 10 years or so, no problems.

 

[jssailem]

Welcome to the SBO Forum.
Many boats are thin shells that hold out the water and flex when pushed.
It has a name. "Oil Canning" or hull deflection. This can be a serious issue for ocean racing boats. It is addressed by adding stiffeners to the inside of the hull.

The construction of your boat's hull was intended to be light in weight. The boat is expected to be used in lakes or coastal cruising.

 

[jssailem]

The crackling noise is an admonishment: "Don't do that!" The cause is likely the internal flexing of the fiberglass fibers.

 

[rgranger]

If it continues to bother you, you can take a swim noodle and a sharp knife and cut it into strips

glue the noodle strips to the areas of the inside hull that are flexing

then cover the noodle strips with resin soaked fiberglass cloth. That will stiffen up your hull tremendously without adding a lot of weight or taking a lot of time.

Then you just need to figure out how to make it look good

lol

 

[Crazy Dave Condon]

@imp6

the hull has a foam sandwich that is inlaid between the fiberglass and when the resin and hardner, hit the foam , it shrinks in thickness. As a result, it gives you structural integrity and weighs less. The hull does give a little above the water line which is a good thing. However I do have a few questions.
The original plans for the water ballast 23.5 came from me and I was involved with the water ballast hunters till I retired. No I am not a naval architect but got a BS in history. We need to talk as I have some issue with that video. I will send you a private message. I would ask that you report back to this thread.
Crazy Dave Condon

 

[imp6]

Thank you @Crazy Dave Condon i sent you a message. Glad to have you here I read plenty of your posts already. All helpful

 

[Crazy Dave Condon]

The boat is a 23 wing keel. I am waiting on some photos and will report back soon