Considering buying a Ply / Ply-Glass boat. What do I need to look for?

[PQDC]

Hi,


Apologies if this has been covered, but I couldn't find "Ply/Ply-Glass" specifically anywhere.


So, the boat I'm looking at is 12 hours away so I want to research it as much as possible before treking over to look at it. My first question is what is Ply/Ply-Glass? It looks like a fibreglass boat so I'm assuming it is ply covered in fibreglass. I'm a little confused by the "Ply/Ply-Glass" rather just calling it Ply-Glass. I've google other boats and many call the boats Ply/Ply-Glass, but there are cats rather than the mono I'm looking at.


If it is just ply covered in fibreglass, then what am I looking for? Wood rot under the glass? I'd most likely get it surveyed as a condition of purchase but wanted to tap into the collective genius of this forum for a heads up too. As a very secondary consideration, would Ply/Ply-Glass make it tougher to eventually get this boat to Cat 2 or 3 for club racing?



The boat I'm looking at is a monohull in the low 30 foot range and the pictures look good (but don't they always?).



Thanks in advance.
Peter

[coopec43]

Things I'd be looking for:

• Who is the designer?
• Who built it? Home built or professionally built?
• What is the design's reputation? (Check forums/Reviews)
• Why is it called ply/glass? Is the deck ply with a fiberglass hull? Is the whole hull ply and it has been glassed over? If so why was it necessary to glass over. I'd be very weary if that was the case because you could be buying a lot of trouble.
• ???

[GILow]

Many of the Hartley designs could fit that description.

Only problem I have heard of with them was some of the motor boat designs had exposed plywood ends on the topsides, which, if not well protected, led to rot problems. Other than that, I've not heard of any particular problems.

Can you give us more info on the design/model?

[GILow]

Oops: Double post

[boatman61]

If its a pro build using Bruynzeel marine ply or similar epoxy ply you should be good.. usually the outer hull is glassed with a couple of layers of 4oz cloth/epoxy for protection against bumps and scrapes.
Quite a few Van de Stadt Doggers were built like this..
I delivered one that is 40yrs old from Perth down to Port Huon in Tassie.. the owners a member on here and did a great restoration on her before the trip so it might be worthwhile sending him a PM and see if he'd care to share knowledge.
His tag is Wotname and he's a very smart guy and a perfectionist as I saw from his refit.
Theres still a few <30ft ply/glass boats from the 70's bobbing around the UK coasts.. Strong boats.
My Tiki 21 Cat was a ply/glass boat.

[Sparx]

Sometimes there are two layers of plywood, then covered on the outside with glass. Devlin has several designs that call for this. The layering of thin ply sheets makes curving the wood easier.

When done well there is a layer of epoxy completely filling the gap between plyies. When done less well there are voids bewteen ply sheets that end up holding moisture, creating rot.

A moisture meter will be very helpful in evaluating a boat built with this method.

Any soft spots are a sure indication of trouble. The plus side is that for someone with modest skills these boats are straight forward to repair.

[44'cruisingcat]

What you're looking for is soft spots, where water may have gotten into the plywood.

Tap with a hard object like a coin, around any fittings such as deck cleats, staunchion bases, winches, hatches etc. If the plywood is wet there will be a dull sound.

Within reason, even if the ply has gotten wet, it can be repaired, cut out and replaced.

[rsn48]

If the original build of the hull was glass over wood, you are much less likely to have problems than some guy covering a problem wooden hull with glass. I have a glass over wood boat and it is 50 years old this year, and still going strong.

One area to look carefully is in the anchor locker where water is more likely to contact wood if the paint etc has chipped when bringing water in along with the anchor, chain and line. Even if it looks good and you purchase the boat, repaint that area with a good sealant paint to doubly make sure of a decent barrier between the paint and wood.

[PQDC]

Hi All,


Thanks for the thoughts. The boat I'm most interested in is a Spencer 32. It's tough to find much info on them online. There was a few forum posts several years ago, but most about larger Spencer boats. Here is the boat https://www.boatsonline.com.au/boats...ncer-32/224373 . Any thoughts would be most welcome.

[Fore and Aft]

John Spencer was a bloody good designer in his day. I have sailed a few Spencers back in NZ and they were pretty slippery. I believe it was his 40 footer Reckless that sailed passed us once doing 17 knots under spinnaker!
I have helped restore a Spencer 32 back in NZ when I was an apprentice. That was over 20 years ago but I think what you are looking at will be double diagonal plywood with fiberglass sheathing. When you survey her look for a wet sponge sound when tapping the hull with a hard object. (You could use the plastic handle of a screwdriver) or any flexing in the timber planks.(glue joins let go). The fact that the owner has opted to spray the antifoul on is a good sign. (he is not a complete tight arse) The red paint (is it rust kill paint?) on the motor also shows he is a fussy owner and obviously likes to keep things maintained.

Good luck, I think for 20g she could be a good yacht
Cheers

[coopec43]

Spencer was born in Melbourne[2] and moved to Eketahuna in 1933. He spent most of his life in New Zealand.[3]
He was a well-known designer of sailing boats of all sizes, including the Cherub, Javelin (NZ),[4] Firebug and Flying Ant classes of sailing dinghies. His designs used thin plywood, hard chines, a vertical stem and stern and light displacement.(Wiki)

[GILow]

Yep, there’s a Spencer 45 next to me in my pen and it looks fast. Needle thin, no room in her despite the length. Fun to sail but I wouldn’t want to spend more than a weekend on her at once.

[Fore and Aft]

Coopec43 Finally someone famous the Aussies can claim as their own. Unlike Russell Crowe, Keith Urban etc!
https://spy.nzherald.co.nz/spy-news/...-by-australia/
Cheers

[Paul Howard]

If the boat plywood was fiberglassed over with polyester resin and is 20 or more years old the polyester may be losing its adhesion to the plywood. If epoxy, it never lets go.

tap around near the water line or just below to see if the fiberglass coating is still well adhered to the wood beneath. Many multihulls were built like this and the polyester resin does not last. A friend with a Searunner 37 regularly pulls off sections of fiberglass with polyester and re applies with epoxy. The wood is almost always OK, just lost adhesion.

[Mike Banks]

Considering a plywood boat is fine.

Buying one is something I would never do again.