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Strip: Shrinking Kevlar?
By:Bill Hohensee
Date: 5/7/2011, 5:31 am

Slowly but surely I’ve been making lots of progress on my first Petrel. What an absolutely awesome design! I even had a chance to do some inlay work around the cockpit coaming.

After glassing the top I separated the deck from the forms some 2+ months ago. I quickly glassed the inside of the deck as the hull sat nicely off to the side with the strongback and forms intact.

Two weeks ago I removed the strongback and forms and glassed the inside of the hull with a nifty orange and black carbon Kevlar fiber cloth (ebay id 120708217998). The Kevlar stiffened and strengthened that hull like a rock! Though I had to ask myself, did it look narrower, or was that a trick of the eye?

Well, 3-days ago I laid the deck on top of the hull for the first time and found … the deck was significantly wider than the hull – by as much as 1.3” at the cockpit! Welcome to my nightmare!

My first guess was that the deck slowly splayed while out of the forms for those 2-months. So in a panic I quickly cranked clamps to the deck looking to correct the difference from the hull. And ending up cracking the deck in 3-places!

Only then did I pull out a tape measure and found what I didn’t expect. The deck matched nearly exactly the forms from whence it came. It was the recently glassed hull that was way, way out of whack.

So here’s question #1 – has anyone else whose used Kevlar experienced this “shrinking” behavior? And question #2, what to do next? My guess with some advice from a wise friend is to sand off a good portion of the Kevlar particularly around the chines, reglass but this time with spacers holding the hull beam to spec as the hull cures.

Messages In This Thread

Strip: Shrinking Kevlar?
Bill Hohensee -- 5/7/2011, 5:31 am
Re: Strip: Shrinking Kevlar?
Bill Hamm -- 5/7/2011, 8:52 am
Re: Strip: Shrinking Kevlar?
ancient kayaker -- 5/7/2011, 11:15 am
Re: Strip: Shrinking Kevlar?
Mike Savage -- 5/7/2011, 3:58 pm