Is Age a Factor in the Seaworthiness of a Glass Hull ?

[daddle]

I have zero worries about my 46 year old Cal hull. I do worry, perhaps needlessly, that after launching off some big wave it's is going to be raining toerail bolts. The boat will look like blown out sneaker...the deck flopping up. Replacing them would be a formidable task. But maybe it never happens...?

[callmecrazy]

Of course 'condition' is the biggest factor, and how a boat was used and where it lived are just as important as how well it was taken care of.

This particular boat has never left the chesapeake. It spent the first half of it's life being raced, and cruised around the bay a few times. Then the second half was spent in 'retirement', only being sailed locally around the Tred Avon. And while loved, not receiving much attention... It's almost enirely original except for regular maintenance, and a motor rebuild about 12 years ago, and some other engine related upgrades in recent years.

It was always hauled out for winter, and never skipped a season of bottom paint...

So, when shopping for a boat, age is not a factor (in my book) but condition is everything. You could easily find an early 90's boat that needs more work than this one... But for overall seaworthiness, I'm not too worried about this old boat

[Adelie]

Originally Posted by Gone2long

... Does the age alone of a glass hull necessarily increase the risk of delamination, osmosis or other problems?

Strictly speaking, for a boat that is in the water and is used, yes age is a factor in increased risk of delamination (due to increasing fatigue history with use) and osmosis (increasing length of time for moisture transport into the laminate.) Even sitting on the hard the boat is oxidizing and slowly outgassing components of the resin used and UV is breaking chemical bonds.

That said I do not believe that age is that important in and of itself up to timespans in excess of 50yr. Age combined with poor initial construction, poor materials, hard use, poor maintenance or some combination of these issues is another matter.

Originally Posted by Gone2long

...
To my way of thinking, a well maintained 30 year old glass boat is not necessarily a liability.

I agree if well built initially using good materials and with only moderate use.

Originally Posted by Gone2long

It would seem that the maintenance of the boat (or lack thereof) plus any possible collision damage to the hull would be much more of a factor than the age of a well-constructed glass hull.

All that and the quality of the original layup and the materials use.

[Gone2long]

Thanks to all of you for your input.

The boat in question is a 1978 Rob Legg 28. This is the first year that this design was launched.

The designer is also the builder and he is well respected, as far as I have heard, in his homeland of Australia.

So, hopefully, the build is sound.

Any more related comments would be gratefully appreciated.

[osirissail]

Since this boat is small and a trailer-sailor boat there are slightly different things to examine in detail.
- - Overall hull integrity. If the boat is on a trailer this is difficult but try to "tap" the whole hull and listen for any significant changes in sound that might indicate some delamination. The hull will be fairly thin so look for stress cracks, indentations, and spider cracks that might indicate collisions with hard objects. Also look especially in areas where the trailer roller and supports have been pressing against the hull. It is possible that if the boat was on the trailer when the owner drove over a significant pot hole or other obstacle for the hull to flex too much where the trailer supports the boat.
- - Same as mentioned by others, the hull to deck joint. Look all around for signs of rusted bolts or fractures in the edge of the deck where it joins the hull.
- - Same thing inside. Look at the bulkheads to see that the tabbing is still intact and not fractured or cracked. Also the condition of the wood bulkheads, if it has wooden ones, to see if water has rotted them.
- - If the boat is a swing keel look for the pivot bolts and cables. If it has a fixed keel that was bolted on then of course the keep bolts and keel to hull joint as mentioned by others.
- - That's about it for the hull structure. There are of course the need to examine the cabin top, rigging, interior electrical wiring and plumbing if any exist.
- - This website might be of interest if you have not already been to it. RL24 and RL28 - Trailable Yachts from Rob Legg Yachts

[osirissail]

Here is a photo I found of the RL28:

[callmecrazy]

Originally Posted by Adelie

Strictly speaking, for a boat that is in the water and is used, yes age is a factor in increased risk of delamination (due to increasing fatigue history with use) and osmosis (increasing length of time for moisture transport into the laminate.) Even sitting on the hard the boat is oxidizing and slowly outgassing components of the resin used and UV is breaking chemical bonds.

That said I do not believe that age is that important in and of itself up to timespans in excess of 50yr. Age combined with poor initial construction, poor materials, hard use, poor maintenance or some combination of these issues is another matter.

I agree if well built initially using good materials and with only moderate use.

All that and the quality of the original layup and the materials use.

Isn't the gelcoat, primer and paint going to provide a moisture barrier and UV cover?

I've heard other people say similar things, but after looking at dozens of old hulls, mostly not well taken care of, I've yet to see any delamination of a solid layup. I've seen blistering, and delamination from core material, but I'm thinking it would have to be an extremely poor layup to delam from fatigue. Even hulls where you can see sunlight through the layup are still as solid as new after 40 years..

When fiberglass boats were first bein built, nobody knew how long they would last. I think maybe that's still true today...

[smurphny]

I think the density of the glass layup and the care with which the glass was laid are the two most important factors in whether a hull is solid or not. It seems that there are problem hulls and solid hulls in the same run of production lines depending on who was doing the work. During the 60s there was also a lot of experimentation going on with resins. The hulls were laid up with a lot of pure mass and a lot of layers of cloth, mat and roving. They are usually pretty bullet-proof.

One method that really promotes water intrusion is the pneumatically applied shredded glass layup. I would be very careful if considering a boat built with this method. It's often too porous and can span over huge voids. As I remember, this started some time in the 70s.

Modern techniques like vacuum bagging entire hull sections has to be producing strong hulls but I wonder if manufacturers may be scrimping on the number of layers they use because of the high price of resin nowadays. IMO there is no substitute for basic mass when you hit something. If a hull deflects with hand pressure, no matter what the designers say...it's too thin. Some very high-priced boats have very thin layups, mostly in the motor boat category, 50' boats that go 50 knots mostly because they are very light.

[psneeld]

Originally Posted by callmecrazy;745526[COLOR=red

]Isn't the gelcoat, primer and paint going to provide a moisture barrier and UV cover[/COLOR]?

I've heard other people say similar things, but after looking at dozens of old hulls, mostly not well taken care of, I've yet to see any delamination of a solid layup. I've seen blistering, and delamination from core material, but I'm thinking it would have to be an extremely poor layup to delam from fatigue. Even hulls where you can see sunlight through the layup are still as solid as new after 40 years..

When fiberglass boats were first bein built, nobody knew how long they would last. I think maybe that's still true today...

UV barrier mostly and gel does slow moisture but only a bit...glass will still saturate I think up to somethng like 15-20 percent in weight.

Primer? If you are talking epoxy barrier...then yes it slows moisture quite a bit but not 50 years I don't think...if you have a true epoxy barrier coat...then get is not needed.

Bottom paint helps a bit but again only very little...

Delam is there...especially up north where you get strong freeze thaw cycles where if there is a concentration of moisture...it does its damage...not common but there...

[osirissail]

Delamination is not something you are going to see easily unless the hull has been in a collision. A bad layup with improper mixture of resin and catalyst along with too much mat cloth or chopped mat and you will over the years (after 10 years) expect to see some delamination. But to see it you need to remove the gelcoat with a gelcoat pealer. Once the gelcoat is removed and the hull sufficiently dried you will notice "dry" white areas and darker areas and areas with coloring in the middle.
- - The really dry whitish area are resin starved cloth and usual sites for delamination. Dark spots are normally blisters which can be physically seen as domes or if deeper seen only as a dark area. Good layup will be in the middle and kind of yellow/brown and uniform.
- - So other than tapping for hollow or delaminated areas, visually there is not much to observe to indicate delamination.
- - Collision delamination is a different story and can usually be found by looking for defects in the faring of the hull in the collision area. Since most FRG boats are done in molds the hull surface is quite uniformly smoothly shaped. A patched hull will be obvious if you look lengthwise down the side of the full and observe irregular areas that don't quite seem fared very well.
- - Finding collision damage should be at the top of your examination list and then looking at the inside surface of the hull for tabbing cracking or separation.

[Gone2long]

More good information. Thanks.

Yes, I know the site. Always try to find an "owners site" when I'm looking at a particular boat.

Regards,

G2L

[VirtualVagabond]

Just a few thoughts...
You are right, Rob Legg is well regarded for his designs and boat quality. The RL 24 particularly. He also built the RL28 and RL34, which at the time was the biggest trailer sailer in Australia. Because of the need to keep the width narrow enough to be legal to tow, they ended up as a bit of a compromise I didn't really like. They also had to be a light lay up to be towable by a family sedan... the 24 and 28. The 34 needed a bit more grunt and were usually behind a 4WD or F250.

The RL 28 was quite popular with hire fleets, so although built to survey, some of them were knocked about.

I only ever sailed on one, and it was a swing keel, not the fixed keel version. I felt it was very tender and way too lightly built for anything other than a weekend trailer sailer, which is what it was designed to be. I certainly wouldn't want to be in it in a big chop or blow.

IMO it would be a big mistake to compare it with the heavy displacement glass boats being built in the 70s and 80s, before accountants got involved and worked out just how little GRP you could get away with.

I would never consider the RL 28 to be a serious liveaboard cruiser.

Now that's got to worth at least 2c!

[David_Old_Jersey]

Short answer = yes (it is a factor).

In the "Good old days" boat builders also knocked out boats down to a price / designed on back of fag packet etc - they were not all hand carved from a single Oak (or Fibreglass) Tree............

But biggest caution I would say (apart from look at and assess everything) is - the PO(s), the older the boat the more likely will have a PO (or 2?) from planet NFI..........

But that's all part of the fun :-)

[osirissail]

Forgot to mention that on centerboard (or swinging keel) boats inspect the centerboard trunk very, very carefully. It is quite common that there are cracks and separations where the trunk joins the main hull. The stresses generated by a centerboard are very high and frequently the engineering of the swing joint and trunk are greatly underestimated.

[smurphny]

As in generally misunderstood building construction moisture technology, the moisture that creates problems is molecular moisture, the kind that goes right through all kinds of materials (steel, concrete, etc.), not water per se. With fiberglass, any microscopic void area will collect water through condensation inside due to temperature differentials in both directions. Warm will always move to cold, it's moisture content with it, and at some point inside the glass, condensation will form. This kind of infiltration can accumulate rather quickly and then take months to dissipate during which time it may go through freeze/thaw cycles, increasing in volume on the freezes. Burst water pipes experience the same phenomena.