Cracked plank, repair of replace??????

[NPeth]

Crack 2.jpg (94.87 KiB) Viewed 7149 times

Crack 1 (450x600).jpg (86.31 KiB) Viewed 7147 times

Wel guys this is the crack along the keelson, its kind of three cracks, the first is 2150mm long and around 10mm wide, the next close to it is 700mm long and is again around 10mm wide, the last is a hairline crack. The previous restorer filled the crack with apoxy resin. No tape or reinforcing was used and only the crack was filled, no resin was on the plank. Not surprisingly this repair did not work The goal is to have a non sinking non leaking usable ski boat at the end of this but money is an object. so what should I do, can the plank be repaired or do I need to replace it? If it needs replacing I am not confident to do this so who in Victoria should I go to?
All advice and opinions greatfully recieved.
Cheers
Nick

[piquet95971]

Hi Nick

For my 2penny worth I would replace the planks.

It would be more fiddly and time consuming than difficult.

It would be a case of removing all the nails and roves from where the plank is fastened through the keelson and where the plank is attached to the second plank and sliding/working it out at the transom end of the boat.

Using the original plank as a template to make a new one then try and slip it back in across the boat. Renail and rove and then repeat for the other plank on the other side.

Is the planking solid timber or plywood? If it's solid timber it will possibly be Meranti or Pacific Maple.

If you decide to give it a go, let me know the dimensions of the timber and I can source it down here in Melbourne and machine it up for you.
Regards
Peter

[bootlegger]

Replace it but dont get your hopes up it wont leak from somehwere else

If you dont replace it now you will be doing it not long after you get it in the water.

[NPeth]

OK You have convinced me, a repaint before using means taking out planks I am pretty sure that the wood is pacific maple, certainly solid planked and I need planks 5m long, 170 mm wide and 15 mm thick. Still not sure that tis something that I want to tackle myself but I guess her goes. Suggestions of timber merchants greatfully received. Any useful videos, hints etc also. Ray you are so wise, milestone to mill stone but here goes

[piquet95971]

These days you are not likely to get PM 5 mtr long but no problems just scarf it together to achieve the length required. I will add more details later
Peter

[piquet95971]

You would probably need timber for the plank wider than 170mm because of the curve in the keelson.
The stock timber that I know of is nominally 19mm thick and up to 300 mm wide. Next time I'm down in Oakleigh I will see what stock they have and get you an idea of the costs of the timber.

The most costly part will be the nails and roves for this exercise. I have a rove punch and nippers that you can use. I'll even come and give you on site advice and help if necessary.

Cheers
Peter

[bootlegger]

If you are painting the hull you are probably better off replacing the plank with plywood. Its stable and will never crack again.

[piquet95971]

Agree with Dave. Get the best ply you can. Plyco in grange rd Fairfield have good stuff.

They stock Hoop Pine marine ply in 2400x1200 sheets.
It will probably work the same or similar price as solid timber.

[NPeth]

Thanks for the information guys, The quest for pacific maple is not going well. The best I have come up with so far is First grade victorian ash which I can get in 5m lengths. Is there anyreason this is not used in boats. The timber merchant seemed to think that it was a more stable timber than pacific maple. I take on board your point about plywood but still like the idea of keeping with the solid planks. I am also not sure about the scarfing, with 2400 sheets and 4850 planks three pieces would need to be joined to rplace one plank. Would the joins be weak spots?? Forgive my ignorance but I am not sure what scarfing wood together involves and what it means to the strength of the boat.
Keep the advice coming guys I really appreciate it.

[Damo]

Hey Nick,
The scarfing of the timber pieces together is pretty straight forward once you have a go. Basically its just bevelling either end of your pieces to suit each other. The longer the scarf / bevel the stronger the join, I have included pics of the ones I did on the side of my hull which were only about 50mm long and joined with epoxy. These turned out extremely strong so I thing you should be pretty confident if you decide to go down this road. I had to join mine on the boat using a piece of channel to hold pressure on it but doing on the work bench you can clamp it together which will be so much easier for you and provide a better job. Cheers mate and good luck!!!