My Turn To Take On A Transom
 

Hello Everybody!!

I haven't been active on this site, but i have been lurking ever since I picked up a 1974 20SF 5 years ago.

The first winter I had it, I rewired the entire boat, as well as new electronics, pumps, lights, etc.. Picked up a rebuilt 96' evinrude 115 , and have been enjoying the boat ever since.

Over the past few winters i have re-cored a few hatches, built a leaningpost/livewell, as well as cushions and other minor upgrades.

As it sits now, This winter I'm planning to remove the motor, rebuild the transom up to 25", repower with something new, replace the 26 gal poly gas tank, new steering, trim tabs, guages, and anything else involved with my upgrades

I figured I'd start a thread to ask all my questions, as well as get opinions on what I'm doing right and wrong.

Wish me luck!

Here's a pic of the my boat "Daze Off"

Nice looking boat. Have fun with your transom.

nice where are you on the project?

I've been chopping away at this for the past few weeks.

So far I have the outter skin removed and all of the old core removed. Getting the old core out of the edges and corners was def a pain in the ass, but I kept at it an got damn near 100% of it out.

Just got all my materials in the mail and next step is to cut the coosa to shape and get all my fiberglass "mise en place" ready. I plan on doing the lay up all in one whack.

I plan to follow this lay up starting from the inside:

Full piece entire shape of transom 1 1/2 oz mat.
3/4" thick coosa, cut into 4 pieces to fit inside transom
Full piece 1 1/2 oz mat
5/8" thick coosa cut into 4 pieces, at least 6" overlap from other coosa pieces.
Old skin on top of it all, clamped down really good.

I'm going to use combination of neat epoxy and thickened epoxy, depending on the layer. Prob thickened for the core and neat for the mat layers.

It's gonna be tough to get the core to fit absolutely snug and tight with the corners and edges of the transom, because of the original construction. There all types of bumps and what not preventing the new core from sliding all the way to the edge. So the plan is to fill the edges with thickened resin, possibly with loose pieces of pulled apart mat, prior to fitting the pieces of core in. There will be about 1/2" space along all the edges of this thickened resin concoction.


Does this sound good?

Your floor is way too nice!!! :)

When FAS redid my transom on a '79 23' I cut away the outer skin like you did but FAS cut the cap on either side of the motor well so he could slide the sandwished marine plywood and glass into the hull as one piece. It doesn't look like you'd have to cut much to do the same. Also save your hull Number!!! Just a thought. Good luck with it .

I'm doing the same thing to my 1978 20'. Got the outer skin off and scraped the old plywood out from where we cut. Got any advice on how to get the rest out around the edges? Yours looks really good...
Thanks

Chisels, drills, claw hammer, pliers, electric chain saw, patients , and beer, lots of beer.

That's about what I figured, but had to ask in case you found a shortcut! Oh well, here we go....
Thanks

Linesider is right! As close to doing it RIGHT as it gets for outboard power.

I got to work the past couple of days and put a good dent in the project.

Got the new coosa core laminated in and the old skin back in place.
Also started scarfing in my joints.

A few questions:

What should the exact height of the new transom be? Factoring in the thickness of the fiberglass of course, what should my finished height be? Should it be measured from the keel along the angle of the transom to the top? Or measured from the keel perpendicular straight up to the top? Right now the new core is at about 25" when measured perpendicular and 26" when measured at the angle of the transom.

When scarfing in the new glass into the splashwell, Should I stick with about 3" of glass around the entire permineter and try to scarf into all the grooves and curves where it meets the hatches? Or just stick with the straight parts of the Splashwell and fill in the edges with thickened resin?

How perfect should I try to grind down my 12/1 scarf? Right now it looks pretty good, but obviously not a perfect even bevel. When applying new glass over scarfs, should I start with biggest pieces first, as recommended by West System, or start with smaller pieces and build up to the largest, as I have read elsewhere?

A lot of work, which I expected, but comping along nice.

See pics for progress:

Your work looks great.

I have replaced 2 transoms from the outside like yours, and I filled the scrafs starting with small strips (2") and progress to larger (3" to 4" to 6"). 14 years on my 20SF using vinylester resin, and 7 years on 23WA using epoxy resin, no issues on either boat after hundreds of hours of use. The West Marine approach does not seem as strong to me.

Keep the updates coming!

Lloyd

The largest first and then smaller is more for corners and laying up over filets. In your case I would start with the small and work out to larger.

A lot of boats are around the 24-25" range but on a seacraft I like to go back to 26-26.5" on the height so that the motor is not jacked up so high off the transom to get the av plate out of the water. It will keep more water out as well.

Do you have to re-gel coat the transom skin before painting
 

I'm a new Seacraft owner and eyeballs deep in the restoration of a 1978 Master Angler. I just realized my transom is pretty much mulch to the portside of the motor well. I found your thread interesting because for the sake of time and expense I need to replace my transom from the outside. I like your use of the coosa board and sectioning it with a second over-lapping layer. By sectioning, can you get a tighter fit along the edges with the coosa core? Once you've replaced the transom skin and faired it, did you re-gel coat the transom before painting? Is it OK to simply paint over the transom after fairing and not gelcoat. My boat was painted before it was put into storage and it's still in excellent condition and I'd rather not ad that step into my hurry to finish so I can get the boat in the water by mid-May. Any thoughts are appreciated

So, I completed this project a few months after I started the thread, and decided to upload the rest of the pics at add the the library of transom replacements on this website.

I know viewing others pics really helped me complete this project, so I figured I’d give back!

Here’s the rest of em

After one season, I had absolutely no issues with the repair

Decided to hang a brand new etec 150 of the back and the boat absolutely flies!

Last couple pics are before and after

Nice work! I am currently re-building a 1970 20SF , thinking leaning post livewell and possibly ETEC 150.

How does that boat sit at rest with the weight of your livewell and etec hanging off the back?

Did you end up raising the transom to 26" as flying frizzle suggested.

Do you have any performance numbers?

Cheers