Starcraft Medalist Transom Rot

[kpg7121]

Hi all! I own an '87 Starcraft Medalist 19 ftr powered by a 3.0 OMC Cobra. The transom is shot so I've decided to go ahead & do the repair. I'm not sure how to proceed so I'll run this past the experts here. The transom is approx. 72" wide. I have most of the old wood removed & here's what i found. Starcraft built the transom using 2 layers of 3/4" plywood laminated together which spans approx 4 ft. of the transom. On each side of this span they finished the transom using 1 layer of 3/4" ply, about a foot wide. My plan is to build the new transom using 3/4" ply laninated together & glassed back onto the hull for the 4 foot section, then finish the transom by butting the 2 one foot pieces back onto the hull using pb thickened with Cabosil to finished off the transom. My question is, is this a good idea? Will doing it this way give the transom enough structure & strength so to speak? I'm not sure if I can maneuver a 72" span of new plywood into place as room is tight in the engine compartment. I've already torn out about a foot of solid flooring & stringers on each side so i could remove all the rot & i hate to rip out more good wood. What do you guys think & thanks for your help!

 

[zool]

Hey kpg, welcome to Iboats resto forum

When you make the center piece, make the second ply 12" smaller on each side with the center 2' double 3/4, then make the wing sections 24" wide and overlap the center ply with each wing, pb that all together and glass it all...butt joints are no good for strength, you need to sister the joints.

 

[kpg7121]

Hey kpg, welcome to Iboats resto forum

When you make the center piece, make the second ply 12" smaller on each side with the center 2' double 3/4, then make the wing sections 24" wide and overlap the center ply with each wing, pb that all together and glass it all...butt joints are no good for strength, you need to sister the joints.

Thanks Zool. Looks like it's back to the drawing board! And i think your plan will work....

 

[Redtruck12]

I agree , sistering / overlapping your joints would be the better way to go.
just because that was the way they did it at the factory doesn't make it proper (or al least for a solid long lasting rebuild.

kpg, you mentioned you cut out a foot or so of stringer, I assume they are rotten too?
i am currently doing stringers and transom on my 17 duo vagabond (Starcraft Capri).

i feel your pain

 

[kpg7121]

I agree , sistering / overlapping your joints would be the better way to go.
just because that was the way they did it at the factory doesn't make it proper (or al least for a solid long lasting rebuild.

kpg, you mentioned you cut out a foot or so of stringer, I assume they are rotten too?
i am currently doing stringers and transom on my 17 duo vagabond (Starcraft Capri).

i feel your pain

Nope, the stringers were fine. I had to remove about a foot of decking/ stringers to get at the bad wood where the transom meets the hull. I couldn't tell how Starcraft built the transom, the wood was totally shot. On my Medalist there are 2 storage compartments on each side behind the rear seats which drop down about a foot inside the transom atea. Unless i remove more decking I'm not sure if i can maneuver the new transom wood into place as these compartments will be in my way, but we'll see.

I'm getting ready to start grinding but it won't be today! Heat indexes in my area will be in the high 90's!

 

[Woodonglass]

Did you core sample the stringers??
That's the only way to know for sure that they're fine.

 

[kpg7121]

Did you core sample the stringers??
That's the only way to know for sure that they're fine.

I replaced the stringers & deck about 5 years ago. The wood that i cut out was solid. It's a long story but this boat has been a lawn ornament for the last 4 years. Apparently the transom started going bad back then but i missed it. So it's time to resurrect it. I went thru it about a month ago with a tune up, fresh gas, etc & she fired right up with a little coaxing. The hull is in great shape, drive & engine are good. I've owned this boat for 25 years & i thought of parting her out when i found the bad transom but hell, i think I'll keep her! So away i go.....

 

[Woodonglass]

Ok Gotcha...Well...Git Er Dun!!!!

 

[kpg7121]

Ok Gotcha...Well...Git Er Dun!!!!

I jinxed myself! I pulled the seats yesterday to give myself more room to work & found a soft spot under starboard side. I haven't pulled the carpet up yet but i suspect the worst. The rest of the floor feels solid, but we'll see. I figure the stringer on that side is also shot. I finally got all the bad wood off the transom. Tomorrow i start grinding.

Btw, that oscillating tool you mentioned. I cut most of the transom wood out with mine. Best $30 i ever spent.