Stringer repair

[Scott Danforth]

My floor is cored with end-grained balsa. You can core with a variety of materials....its just time and money

 

[ondarvr]

Has anyone any experience with the cored foam on flooring

It works well, the actual strength isn't an issue, you just need to make the top skin thick enough so you don't get any impact damage.

 

[bjf66]

No Title

well had a busy weekend took motor, Z-drive out, and proceeded in cutting stringers down
managed to take off 35mm in height, this should be plenty
The centre stringer on outside is still 230mm Hx60mm (9"x2.4"), so still plenty of strength
Gave me a good opportunity to check my lamination skills, seems a little air pocket when I was filleting the radius to blend sandwish plate into new stringer, but the rest seems okay

I was counting on how dam had this stuff was
I was using a Ryobi saber saw to cut, I broke one I had been using since the start of the boat rebuild, and then went an got a replacement under 12 month warranty, and then broke the new saber saw 1/2 day latter
Needless to say took that back and got a new saber saw, i love Bunnings hardware, great service

opened the drain holes through inner stringer so water can drain into centre cavity
Both stringers level backwards and across

Cut floor section
cleaned by some of the older chop matt in outer stringers

Will put some cloth down on the inside of the outer stringer and across on to inner stringer just to strengthen a little

In two mines to use the Gurit 13mm ore board or marine ply which I have for the floor

will fibreglass in new small centre stringer to finished off
will fibreglass top of inner stringers in fabric and Vinyl ester

More dust in garage
after cleanup

will start attacking the front section, to remove ballast tank and trim down the centre stringer

 

[bjf66]

glassed outer, inner stringer 600SM, an 17oz fabric

 

[Deroct53]

Would anyone happen to know if the stingers of a 1987 Sea Sprite 175 Fish N Ski are fiberglass or wood? I was given one and the floor has to be replaced but haven't gotten into it.

 

[Scott Danforth]

Would anyone happen to know if the stingers of a 1987 Sea Sprite 175 Fish N Ski are fiberglass or wood? I was given one and the floor has to be replaced but haven't gotten into it.

I suggest starting your own thread vs hijacking someone elses thread

 

[bjf66]

No Title

cleaned up between stringers, around floor, added 40x30mm hard wood centre stringer, to fill the void left in removing the old stringer
filleted either side with PB, needs to be cleaned up
However ready for next step to add 600 CSM and 17 or 27oz fabric along floor

 

[bjf66]

No Title

had big weekend in garage flbreglassing
saturday
- aid the (2oz) 600CSM, 3m x 0.350m long
- then (17 oz) 637 grm fabric over top 3m x 0.45m long

sunday
- laid more 600 CSM x 2m x 0.3m long on inside stringer on both sides
- then 637 grm fabric over this 2m x 0.4m inside stringer
- capped RH stringer with 600 CSM, coming over stringer either side by 0.2m x 1.5m long
starting to see end of the floor/stringers
need to make decision on whether to put the floor back of leave exposed

Purchased some other aluminium water cooled exhaust that may offer a little more clearance
I've decided I'll run the twin turbo 8.3 litre (509") BBC in boat

 

[bjf66]

No Title

 

[bjf66]

No Title

decided to cut some wings/supports between stringers, as need to support floor so thought add some strength
PB in, need to clean them up, and tab them in
not sure whether should be adding some foam under the floor for buoyancy

anyone have an opinion on when to/or not add some foam buoyancy????

 

[Scott Danforth]

Add the foam

 

[Baylinerchuck]

+2 on adding the foam

 

[bjf66]

Was in discussion with another boater last week who has ocean raced 25ft mon hulls and used fixed surface drives in past
He was suggesting to use a urethane disc in between the Dana spicer flange/yoke as a shock obsorber to give drive train a little movement

The companies which were suggested were polyflex or isoflex

Has anyone used these types of flexible couplings as interested in some feedback

 

[bjf66]

http://isoflex.com.au/
http://polyflex.com.au/flexible-disc-couplings

 

[bjf66]

No Title

after some discussion ended up purchasing the Isoflex IFC 4700HT flexible coupler rated to 2100 Nm (1550lbs) torque, 2 days delivery, US$320, nicely machined even fits on the Dana 1410 male/female universal flanges
a few pictures fitting to drive and gearbox

 

[bjf66]

No Title

tabbed in using 600 CSM the 50mm pvc pipes cut in half fr the drainage to rear

 

[bjf66]

No Title

picked up sheet of Gurit cored board, for approx A$105 with tax for 2.18x1.02x12mm sheet
cut out left hand side approx. 1500x230mmx12mm
wet board first
rolled 1 x 2oz CSM and 1 x 18oz fabric onto bottom,
took approx. 0.5kg of resin
made sure the the cored board was siting on straight supports

will most probably use for top floor boards 2oz CSM + 33oz fabric, should be strong enough
will do the top glassing tomorrow

 

[bjf66]

No Title

foaming plan:

Now starting to look at how to go about the placing of pourable foam under floor
so will pour foam into the pockets where have supports on inner stringer

Now thinking about how to pour the foam into outer stringers, marked in red on attached photo, as far as Im aware this stringer is open moving all the way forward, although most probably easier to cut a hole into floor and see if I can get my phone in there to have a ,look
Im assuming would cut some 50mm Dia holes at 1 metre lengths and pour in at different interviews
I calculated I needed:
open stringers: 1.2kg each side
Red cavity: 1.2kg each side
Green cavity: 6.6 kg either side
approx. 16kg not incl wastage...20kg

Not sure whether I should be adding the foam up into the bow?
Have been looking at Ecofoam GP330, approx. A$330/20 litres
http://media.erapol.com.au/wp-content/uploads/files/products/foams/Rigid/GPFoam/Ecofoam GP330.pdf

Or does anyone know of a polyurethane foam which is more closed cell??

 

[bjf66]

one other question I have
I haven't touched the front half of the fllor of boat, as stringers were in good condition
therefore the cavity under floor is open

There are no drainage pipes there
would i be best to
1. just pour the foam into cavity, as back half under floor has drainage pipes, working on principle the water should run to back of boat ?

2. cut into floor and add the drainage pipes and partly remake floor as I have in rear of boat, prior to pouring the foam?

Or any other suggestions???

 

[Scott Danforth]

Pour foam.....go boating....you wont have the boat 20 years from now