Rwgreen2384

I have a 2000 python and the stringers look to be made out of 2x6 lumber . But they are rotting and need replaced. Is it better to go back with 2x6 or make new ones by laminating ply together. And what material to make them out of would also be a great help. Any info would be great. Thanks

vintage chromoly

iTrader: (3)

Laminated plywood. Scarf it in.

Rwgreen2384

Thanks for the response. I was actually reading up on one or your old threads. How many layers of play did you used l, how thick, and what type of material.

vintage chromoly

iTrader: (3)

I used cabinet grade birch plywood, 3/4" thick. Two pieces clamped up with glass mat and slightly thickened vinyl ester resin. I have 2 layers of 1708 over the stringers with 2 more layers of 1708 tabbing at the hull/stringer joint.

Rwgreen2384

If you don't mind me asking what was the reasoning from switching from the 2x8 to the laminating ply. Strength or rot reasons?

vintage chromoly

iTrader: (3)

Stronger and no cupping or crown like dimensional lumber has.

phragle

iTrader: (3)

RWG where are you located?

hoodoo

Just curious, why is wood still the go to material so often, when there are composites available?

phragle

iTrader: (3)

Wood is cheap easy and pretty foolproof. plus handles compression from tightening motor mounts and stuff better.

glassdave

iTrader: (1)

Yep, the compression loads dont work well with composite materials. I have done several complete structure replacements using Coosa Bluewater 26 throughout with the exception of engine stringers and transom. In low load low HP applications its fine but for our rough environment you can get some failures. If i do do a transom its three layers of half inch with a full layer of 1708 inbetween each and all through bolts are backed by a large stainless plate. Truth be told i still just prefer wood transoms, every race boat we ever had with a composite transom had some sort of issue. Its fantastic stuff but has to be used properly and with VE resin at a minimum. I've got a Donzi F1 race boat in that is getting the works, full composite rebuild but race layup wood transom and stringers.

Dimensional lumber is a poor choice in any marine application. I cant believe any builder would approve for any reason, its not even like your saving that much money either.