Modern Materials for Stringer Rehab

Hey guys,
Im new to the group and have been loving the conversations through the forums. Thank you!

I recently picked up an SN '80 with less than 1K hours, and considering the age, its in good shape. As most of the early fiberglass SN its likely that ill be doing a stringer job in the near future. With this in mind, Im currently doing some research into Coosa board as a substitute for doug fur stringers. I've read many forums and understand the different arguments pro and con. One topic i haven't seen is the one where modern materials like Coosa are used with carbon fiber or kevlar. Any thoughts in this direction?

Additionally, I'm interested in fully documenting my rehab and recording the updates and improvements including pattern making for the stringers and related bulkheads. unless i can buy them form a reliable source. Any one know of such a thing? As I've worked in the design field for the past 25+ years, I'm computer capable. (CAD Sketch-up etc.)

Any info would be greatly appreciated.

I think it would be overkill. Look how long they lasted originally with what CC used. Use quality conventional materials along with the Coosa and quality workmanship and you'd be good to go IMHO. Either that or just do the glass build up with nice crisp 20's

Hi Guys,

Great quote on the crisp 20"s. I have less of those and more of the time and craftsmanship required no matter the materials. so If only to satisfy my curiosity i feel i need to at least dream of a world where everything is possible. Ha...

Nothing wrong with dreaming Greg. Joe and Tim are the go to guys on Coosa builds. Not sure if Tim had a thread on his or not,I would be surprised if there wasn't. Someone will point you in the right direction.

Yes, Indeed! I lost some sleep last night reading Tim's treads. Loved them and learned a lot. His treads brought me back to my CNY lake where i grew up and where i still visit family. A great series of comments and advice from the CCF community. Cheers!

You may be confusing the players as JoeinNY and I are about 4.5hrs apart.

http://www.correctcraftfan.com/forum/forum_posts.asp?TID=16014

Yes, so sorry for the mix-up. Tim and joe seem to be synonymous with coosa builds in this forum.

still a newbie...

Gneil wrote: Joe's coosa stringer build is a bar well placed. I wonder if the coosa would support an 440 turbo arrangement?

Close to 10 years in and I am confident my Coosa unibody boat would hold just about anything thrown at it, its been beaten savagely by waves regularly, been rained on, snowed in, set on fire, filled up with water over the floor numerous times, pulled enough skiers to bend the pylon, fed enough torque to twist off prop shafts, and trailered tens of thousands of miles. It still feels as solid as the day it was built.

Regarding the more expensive materials it becomes pretty hard to justify, most of the areas the glass layup is doing more than one thing, like providing impact resistance, sealing materials from water, or holding screws, and not just resisting tensile force. The build up needed for the other requirements ends up being more than adequate for the strength requirements so going with a higher strength to weight ration carbon or Kevlar isn’t worth the expense and increased difficulty of use. In general if you are hand laying up multiple layers of composite and not vacuum bagging it then you are using so much more resin weight than what is needed that it is kind of silly to think of saving a couple pounds with fabric.   -

Gneil wrote: Ok, here is another idea....(slightly off topic) Dust collection during the stringer demo and prep. Has anyone heard of grinding and sanding with water? I know this may sound obvious (gel coat wet sanding on the exterior) or even ironic, but the boat is a sort of bowl and the waste could be concentrated in a container for disposal with a simple filtering sys. also it might help with the itchy factor and clean-up could be managed on an ongoing basis. Any thoughts?

Cutting or grinding glass use pneumatics with a water spray, like at the dentist.
Aim and zip tie a small nozzle at the cutting wheel or whatever, just make a slurry, virtually no dust.

of course still don all ppe

following the water grind tread...

Tom,
The zip tie solution may work just great!
I Think Bosch makes grinder attachments that have several attachments similar to what you are talking about that are used for stone and concrete.

I've cut a lot of tile and related materials both wet and dry and you never really want to cut dry if you have the option.

could be a wet mess, but it might be better than a dry one.... Still planning.
Thank you for your insight! I love this tread thing... It's a first for me.   

I'm in the process of doing wood stringers and a Coosa floor. All with epoxy resin.

uk1979 might already have drawings of a factory 70-81 ski nautique structure. However, many of us have chosen to modify the factory design for many reasons.

Again, Thank you Joe!

Ill see what Rodger has to offer. I did realize that your boat is a 2001 hull and mine is a couple years older than that design. But its the concept and implementation that is so impressive to me.

Gary S wrote: ... Either that or just do the glass build up with nice crisp 20's

Pete, any idea what the proper moisture content of US currency should be prior to layup??

Blockchain technology = stronger core material

does it matter what kind of lay-up you use depending on what type of water the boat will be floating in?