Advice on transom , stringers and floor rebuild

[carlos515]

I am restoring a 1991 Sunray Prelude 20 footer. I have used epoxy to glue the plywood panels together for the transom. I am not sure of what to laminate the transom back in the boat with. Epoxy is what I would like to use as it is the strongest , but it is expensive if I will have to do the stringer and floor also. I have 1808 glass and csm stitched mat which is binder less.
My question is would I be wise to use polyester resin for the restoration or vinyl ester ?
I have 1 stringer removed and I will have to remove 4 feet of the second stringer from the transom forward. I also need to redo my engine mounts.
Thanks, Carlos

 

[carlos515]

I have opened up the motor mounts . They were composed of layered plywood. I will use Douglas fir 2x6 stacked on flat to remake the mounts. The second stringer is wet for 4 feet from transom forward. The stringer looks like Douglas fir 2x10 . I asked about polyester or vinyl ester because I was hoping to gel coat the floor when done and put an anti slip finish on.

 

[Scott Danforth]

Is there a reason you want to use epoxy? Your boat was poly resin

If it was me, laminate ACX exterior plywood with titebond III, make new transom, stringers and bulkheads. Tab in with CSM and 1708

Drop in floor and tab in, foam

Cover with 1708. Finish with gel

 

[tpenfield]

Vinyl Ester, if you are concerned that polyester resin is not good enough. I like using VE resin, because the working time before the resin starts to harden is longer than poly resin and the adhesion is better.

No real need to use epoxy in a general re-build, and Poly and VE won't stick to epoxy very well, if at all.

 

[jbcurt00]

....No real need to use epoxy in a general re-build, and Poly and VE won't stick to epoxy very well, if at all.

Nor will gelcoat, as its polyester based

 

[carlos515]

Thanks for the replies all .
I was just concerned about strength and waterproofing with epoxy. I have not worked with polyester nor vinyl ester. But I will order a few pails of poly and some ACX exterior plywood. This is half the price of the Baltic plywood.

Scott , when you say make new stringers , do you suggest making them out of plywood instead of Douglas fir 2x10's ?

Thanks,
Carlos

 

[tpenfield]

I would make stringers out of plywood . . . I think you will have better strength-to-weight.

 

[carlos515]

Thanks for the suggestion of plywood for the stringers.

 

[carlos515]

One more question .
Would it be wise to put the stringers directly on the hull , or put some rigid Styrofoam 3/8 inch thick between the stringers and hull? My thinking is to reduce hard spots .

 

[tpenfield]

1/2" of Urethane Foam would be good - the resin will dissolve styrofoam.

 

[todhunter]

Use something to space them up and then pipe PB underneath. I only had mine lifted 1/8 - 1/4 inch. It doesn't have to be much.

 

[GSPLures]

I used tile spacers then piped PB in the center and both ends to lock it in place. Once that cured I removed the spacers then PBed under the rest, made the fillet, and tabbed all at once. I did it that way so it was all wet on wet. They came out super solid.

 

[carlos515]

Good suggestions .
Thanks

 

[carlos515]

I have been reading that replacing the stringers on a roller trailer is not a good idea. I am at the point of grinding down the old stringer tabbing . I decided to look under at the hull.....needless to say , The rollers are making a small dent in the hull. No cracking in the gel coat.
So , would it be wise to take the boat off the trailer and block my boat at the stern chines and bow center hull? Before installing the new stringers. I have not removed the cap .

 

[GSPLures]

I have been reading that replacing the stringers on a roller trailer is not a good idea. I am at the point of grinding down the old stringer tabbing . I decided to look under at the hull.....needless to say , The rollers are making a small dent in the hull. No cracking in the gel coat.
So , would it be wise to take the boat off the trailer and block my boat at the stern chines and bow center hull? Before installing the new stringers. I have not removed the cap .

If you are noticing any deformity in the hull I would. Possibly you can slide a board between the roller and hull, as long as you are 100% sure the setup will be stable. I did that to mine because my bunks were sagging before I replaced them and it worked well.

 

[carlos515]

Thanks, I put some boards under and a couple of jack stands under the rear chines.

 

[carlos515]

What is the consensus regarding a below deck ski locker? I was thinking of filling the void with foam. Was thinking to build a wake tower with brackets for skis and boards. My thinking is that the least amount of holes in the deck....the better. Have I overlooked anything ?

 

[KJM]

What is the consensus regarding a below deck ski locker? I was thinking of filling the void with foam. Was thinking to build a wake tower with brackets for skis and boards. My thinking is that the least amount of holes in the deck....the better. Have I overlooked anything ?

I saw that you were grinding down the old tabbing for the stringers. If you have the old bad wood completely out, i left the channels as guides and supports to keep the new stringers in place. Just filled the channel bottom with thickened resin and dropped the new ones in. The channels were only about an inch deep. worked well and then i tabbed on new 1808 after the resin hardened. As for the ski locker, I'd leave it. Get a new hatch and it will look great and you can never have enough storage. Also it don't hurt to have a place where you can see whats going on below the floor, as in a leak....

 

[carlos515]

Thanks, Good points.

 

[todhunter]

The storage is not worth giving up. Just seal the edges of the opening with fiberglass.