Trojan Boat Forum

The upper deck floor on our 73 tri cabin has begun to sag to the point where I think I have to deal with it this winter. I thought there was a posting a few years ago about this issue, but when I search I can't find anything on this repair. Can anyone that has made this repair give me a few pointers?

There's two ways to deal with this. The correct way is to remove the upper fiberglass layer, then remove the rotted core material, replace the core material with either balsa or foam coring, and then put a new fiberglass layer on top of the coring. While this is the correct way, it is also the expensive way.

A less expensive way is to use expanding polyurethane foam. For coring you will want to use 8 lbs. density foam. You can purchase the foam at www.uscomposites.com/foam.html as well as other places on the internet. To use the foam, drill 1/4 inch holes where the floor is weak. Mix the foam according to the directions and use a syringe to inject the foam into the empty space. Let any excess foam come out of the holes. Once the foam hardens you can cut the excess foam with a razor knife and dispose of it. I used MagicEzy 9 Second Chip Fix (www.magicezy.com) to repair the 1/4 inch holes with very good results. This approach isn't as good as replacing the coring, but it will provide the needed strength to stop the floor from sagging.

That's a great idea for soft deck repair and I plan to use it this winter to repair a soft deck around my anchor.

The problem I need to fix is at the helm or rather the deck above the aft cabin. It's a teak deck. Most likely a plywood. The structure below which is the ceiling in the aft cabin needs structural support added. I haven't taken down the headliner yet to look. I'm just wondering if anyone has done this repair to their tri-cabin.

I would not expect it to be plywood under the teak floor, not rigid enough.
My guess is you have a fiberglass cabin roof and floor under the teak which is balsa cored for strength. I wouldn't touch the headliner. Does the Teak floor have poor seam caulk &/or screw holes? If so it may be worth taking it up to do the process Big D suggested.
If the Teak is good then maybe you could do it from underneath..... I don't like working against gravity

I have had portions of the headliner pulled back in the past and the deck is plywood. The teak may be planking laid on the plywood. It's not soft, it' has bowed over the years. The entire floor is bowed in (sagged). I was planning to use a car jack and push the floor up from inside the aft cabin using the stringers for vertical support and then install a header made out if white oak. If the oak can't do the job I guess I'd have to fabricate something more expensive out of aluminum. I remember seeing other comments about this repair for the older Tri cabins.

I stand corrected.....

I need advise my 32ft flybridge the floor on my bridge is geting soft in a 2ft sguare area i have researched a product called injectadeck even spoke to inventer anyone have this prob

The right way is to cut it open and replace the bad coring . But that's not real easy Injectadeck looks interesting . I never heard of it before . It is pricey but if it worked and lasted it would be worth it but it could no better then spray foam at 30 X the cost . Wish I could give you better info . You could try it but you could be throwing your $$$ money away and have a mess to clean up or a solid deck .