Late 80s Tristar/Prostar Bouncy Floor Panel
Looking for some opinions or suggestions after searching the forum for a similar repair. Floor access panel between the motorbox and the rear seat has seemed a little bit bouncy (deflecting) for a while. Also, the motor box hinges were wallowed out and not holding in the floorboard (common to many years on TT). So, thinking I would try to address both issues at once, my plan was to slot the forward edge of the floor panel (motor box side), insert an aluminum angle, 2" x 5/8" x 1/8" thick that would be long enough for throughbolting the hinges and would also provide for stiffening the edge of the floor panel. The angle would go full length of the panel and sit on the ledges on each side of the opening.
Once the floor panel was removed and the carpet peeled back, some rotten wood was discovered in one corner of the panel as well as around the hinge screw locations. The panel construction on my boat consists of a molded fiberglass floor panel (edges turned down about 3/4" on three of the sides). It looks like a wood panel was then glassed into the area and coated with a layer of mat and resin to waterproof it somewhat. So, I tried cutting a 2" slot of the wood away hoping to get back to some solid wood, no luck. I then decided to go ahead and remove the entire wood panel back to the molded 'glass piece.
I then spent some time fashioning a replacement piece of wood (3/4" thick pressure treated s.y.p.) that I would glass in similar to the original. The long edge where the angle would go was rabbeted down so angle would sit flush. The short ends were tapered down flush the fiberglass turned down edge. The problem was that the fiberglass wasn't level where the wood was going sit. There is a gap of approx 1/4" in the middle area. The thin piece of 'glass left after wood removal is pretty weak and would not support anything by itself.
Stop, three options to consider:
1. add a few layers of mat and resin in the middle of the area to build it up to level with the perimeter. Then 'glass in the wood, the angle etc. as originally planned.
2. forget the wood altogether and just add layer after layer of mat and resin to build up the thickness of the panel until it is flush with the turned down edge. Panel would then be on the order of 1/2 to 5/8" thick of solid fiberglass. I could still insert the angle if desired or just put some backing plates at each hinge location. The question I have with this method is the strength of the panel when complete? Would it support the weight of people standing on the long edge without deflection? (edit) The span of the panel is about 29", ledge to ledge.
3. The other option was to separate (sawcut) the piece of the panel that forms the floor (discard) from the riser and remainder that forms the seat base. Then just build a new wood floor piece, covered and waterproofed with 'glass. This piece would be approx. 10" x 29". If any furture problems developed, it could be fairly easily replaced again. Anyone ever try this approach?
Sorry for the long post. Looking for seasoned and valued TT opinions or other suggestions at this point before proceeding. I like to try to keep things original as much as possible.
Couple things from reading all of the other posts on this subject:
Yes, there is still wood in an '88, at least in mine, in this location (non-structural) floor access panel.
Apparently the later boats had the aluminum honeycomb panel which seemed to present its own problems.
The turnded down edge is waht sits on the ledge on each side. THe edge cannot be any thicker since the floor panel would then project above the adjacnet floor level.
Picture of floor showing the rotted (darker areas) wood. The wood used here is not plywood as one would think but instead was a vertical grain pieces (blocks) of wood (the grain was perpendicular to the floor, not parallel like plywood.
Picture of the fiberglass panel with all of the wood removed. Notice turned down edge on three sides.
1988 Tristar 190 Sport, 351W w/GT-40's, 1:1 Velvetdrive
Last edited by MikeyOrange88; 12-03-2012 at 10:14 PM.