Thread: Qld/northern NSW plywood delamination repairer

try Shooting the breeze... - General Discussion forums | Seabreeze, page 1

Aussie forum that covers every type of non powered water sports there is a huge section somewhere on surfing and defined into states.

Thanks, will try it when I get back from a trip.

If Tony's suggestion doesn't work out, BG, may I suggest that you go to the nearest surf club or even surf beach and ask around. There is an incredible skill base in surf board shapers and restorer's - most do not have a shop front, so you have to find them. Unless they have gone surfing!

Many surfers are interested in the history of their sport and culture, and the 1960's is especially significant.

Thanks Graeme. I asked a vintage board collectors sire and asked a few shapers, so thought I'd try woodworkers. Bob

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Thanks Graeme. I asked a vintage board collectors site and asked a few shapers, so thought I'd try woodworkers. Bob

Couple things come to mind: Do you plan to use it to surf. And who made it.

The reason I ask that is: 1) If you plan to use it and it's made from non-marine grade ply, you're wasting your time and money as it will continue to delaminate, even with the best fiberglass job.

2) Who made it, if that's possible to find out, will hopefully allow you to find out what materials it was made with to determine whether 1 is feasable

I believe it was non-marine
ply and glue. The guy who made them is long dead. West epoxy was suggested as an option. I had thought I'd ride it.

I'm in my late 60's and grew up on the beach with a chippy for a father. There were a few common types of plywood 'surfboard' in use in our area in the 60's and dad made some of each type.

The simplest was a precursor of the foam boogie board, and was a single piece of plywood with the corners rounded to a fairly large radius (30-60mm radius) and the edges rounded to minimise the chance of splinters. These were either steamed or heated and the front end curved up over about 300mm to prevent the nose digging in to the water. These were typically just coated with marine paint or varnish.
The second type were surf skis, with upper and lower plywood skins separated by framework of ply or lightweight timber. These could be for single or tandem paddlers, and were equipted with loops that acted as foot bindings for the paddler(s). They had a significantly curved side profile along their length, narrow bow, spreading to full width around the seating positions, then tapering completely to the stern. These averaged about 5m in length and 700mm width at the seating position. Paddled with a double ended paddle similar to a kayak paddle but maybe a little longer, with seated paddlers. Typical finish was marine varnish.

The third type were a plywood version of a typical stand up longboard finished with marine varnish or marine paint. These tended to be superseded by units with carved balsa cores and poly resin and fg cloth then later with carved poly foam cores and poly rein and fg cloth.

I don't think that there is much that you can do if the ply has delaminated, short of removing it and replacing it with marine ply. Then the structure becomes important, as it may be delaminating as well, meaning that you really are making a new board and using the original as templates or patterns.

Delamination occurs because there were voids in the ply when the unit was made, it has been misused which has caused micro cracks in the surface finish and veneers allowing moisture to penetrate and break up the glue bonds between veneers, or it has been left exposed to weather and UV radiation and the surface finish has been allowed to deteriorate and allow moisture to penetrate the veneers.

If delamination occurs, the individual veneers in the ply start to loose the bonds between them and the structure is significantly weakened, and generally the outer layers start to expand and bubble, creating recesses to trap moisture and continue the delam process. It becomes almost impossible to get the these buckled layers back to their original position, or to seal the entry points for moisture to prevent further ingress. I suspect that encasing delaminated ply with an epoxy or similar will increase the weight, make a start to sealing the points of moisture entry, but probably result in the the epoxy coating delaminating from the ply within a couple of years due to poor bonding (you can't get the failed original paint/varnish out of the pores of the veneer to allow the epoxy to key into them) and movement in the ply during use, transport, or as a result of environmental change, board dry and in the sun heats up, then enters water and cools rapidly, then heats slowly when it is bought ashore.

Pretty good advice from Malb.

One thing you learn fast, or at least should learn, with wooden boats / surfboards etc is that preparation is everything! then maintenance is king! That includes selection of the appropriate materials for the task.

I'm also a 'boomer' but was never a surfer however I dabbled around in wooden boats, from making them (amateur & professionally) to sailing or fishing from them. In the 1960's & '70's we did not have the glue technology we have today, both in the manufacturing of ply's or assembly. Quite a few of the early Game Boats in FNQ were built from marine ply in boat yards in Cairns. I earned pocket money in boat yards doing all sorts of tasks from careening, construction, fairing hulls, to 'tie wiring' frames & reo mesh for 'ferro' hulls and pontoons.

We built hulls from marine grade ply (ply fishing flatties, 'Moths' 'Gwens' 'OK's' 'Sabots' etc) and also from triple diagonal veneers (amateur builds of 16' racing sailing skiffs) before the "tupperware" (light weight fiber glass) hulls emerged. We used epoxy glue - a fore runner to the West style systems in use today. Also done quite a few repair jobs.

Voids in any of the materials used are a killer! Once water is trapped inside the construction or materials it becomes a slow process of degradation. Unless its a clinker or carvel hull, then moisture is your friend. IF the internal surfaces were not originally sealed - then it will never be practical to put the board back into service.

No amount of "applied finish" can fix poor substrate materials, or construction IF the board is to be put back into active service. As a restoration for display only there are way and means to cosmetically fix the board.

Firstly, the board will have to be thoroughly dried, internally and externally! This will require stripping of all of the existing finish and perhaps even cutting holes into any and/or all void spaces in the board. Then its the long slow process of de-humidification. Once you are confident that it is fully dry then the painstaking process of removing bubbles, filling substrate voids and repairing / replacing veneers, or sections can commence.

There are all sorts of tips / tricks available such as using a steam iron to activate the lignin in the veneer to make it supple enough to "press" back into shape / conformity with cauls and weights or braces or what ever "device" it takes to do the task.

Then there ways and means to fill voids using injection techniques - syringes etc. Tap the affected area lightly to identify the extent of the drummy delaminated area then carefully drill shallow 'thru' holes into the veneer for entry and exit "ports." It may require multiple "ports" for each area. Again use cauls etc and your friend wax paper or 'cling wrap' as a mould release between board and cauls. Card scrape off later.

... and .... the steam iron + glue injection can be done in the one operation for small voids IF one is organized and efficient.

Excellent posts by Malb and Mobyturns.

Thanks malb and mobyturns. When I'm home in a week or so I'll post photos. For simplicity I called it a surfboard, it's a 1960s Hawaiian Paipo Nui paipo board, a bellyboard. Malb how long were the bellyboards you described, do you have any photos of them? I have a website documenting the use of these boards.

Nice read - Before the boogie board: Hawaiian paipo boards (brisnet.com.au)

Thanks Mobyturns. If you search bgreen + bellyboard + Australasia you'll find the Oz pages

I know it's not looking good. The first photo is the most delaminated section, the second photo is the deck and the third, the fibreglassed bottom, which should be sanded. The plan was to reglass top and bottom with 2oz cloth. Turps was recommended to remove glue residue, but there are still some stubborn patches. Any other suggestions?HPD6.jpgHPD7.jpgHPD9.jpg

Further to my posts, here is an updated photo. Restoration by Mike Taylor ( MTOARS - Carpenter /Joiner) of not only the board but a surf ski paddle that was missing a blade. Great job.

PN1.jpg