transom rebuild help

CharlestonSC · #1 03-12-2011, 06:51 PM

The plot thickens, planed to just do some patch work but as I dug into it the whole thing was wet so I decided to rip it all out from the inside.
looking as I pulled it out looks like wellcraft made the transom out of 1.5'' thick plywood and put 2 relief cuts to let it curve a bit.
so I was think of just using 3/4'' and epoxing it one piece at a time and clamping it to the back of the transom?
any suggestion?
I have seen some pictures where other members make it in 3 pieces.

Richie Rich · #2 03-12-2011, 07:40 PM

That will work fine....in fact, if you want it to bend even easier, use 1/2 inch ply and just add more layers...thickened epoxy will work great....pre-wet both sides. Use a notched trowel about 1/4 inch deep and sweep it in one direction to allow air to escape and the putty to spread and clamp it in one at a time...use as many clamps or through bolts as you can to spread an even load, just don't squish everything out...just enough to see the resin ooze...then the remaining layers can be glued and screwed with self tapping screws and fender washers....just like you see being used on boats being built over a frame with wood...when cured, remove the screws and do the next layer. Since your prepping/grinding the existing glass, I would replace what you ground out with a layer of 1708 to make up any lost glass thickness and uneveness....don't need anything between the layers of wood except epoxy. Post some work in progress pics!

CharlestonSC · #3 03-12-2011, 09:08 PM

Here's the start need to grind the thin layer of wood off so the epoxy has something good to bond to.

Richie Rich · #4 03-12-2011, 10:22 PM

Looks really good.......you're going to need to grind the sides of the gunwales as well to allow you to wrap around each layer of glass for the inner skin.....probably 4 to 5 layers with a 2 or 3 inch progressive overlap on each layer...you want the same total skin thickness or a little more than the original. Also once you get the core in place, make nice fillets around the perimeter with epoxy putty and then tab the perimeter with a few layers of 6 inch tape, then put on your full sheets over everything.

CharlestonSC · #5 03-13-2011, 08:24 AM

Yes, I'll grind the gelcoat on the sides to get a good overlap, fill in any voids with epoxy puddy. I have a a 60'' roll of 40oz cloth with heavy mat then a heavey cloth on top of that, looks as thick as what wellcraft used.
With fiberglass it is best if I do the edges then let that dry then do the large skin?
Meaning if you cover up something you just glassed after it has started to kick will it be best to let that cure out or can it be layered by another?
Thanks for the help, and I'll keep this updated

Richie Rich · #6 03-13-2011, 10:26 AM

Actually, its better to go wet on wet to keep the chemical bond going....just because the resin begins to kick, its still considered wet on wet for a few hours...depending on who's resin you use, they will tell you how many hours you have to continue layering before its required to sand again.....if using slow hardener, you can go several hours after its kicked...even up to 12 hours on some brands depending on temperature....it usually takes up to 24 hours to fully cure.

Once the core is in place....pre-cut all your glass, the tabbing and full sheets and have them ready......then make your putty fillets and let it just start to set up and then add your tabbing tape...if you do it right away, you may squish out the fillet, so just let it set up a bit but still tacky. Wet out your tabbing and let the layers overlap a bit...in other words, if using 6 inch tape, one layer has 4 inches on one side of the joint and 2 inches on the other, then the second layer would be layed on the opposite side, creating the 2 inch overlap......let that start to tack up so it doesn't slide on you when putting on the full sheets....then pre-wet the core, let it start to tack and then add the glass and wet out completely.

The 40oz glass is pretty heavy...I like using 17oz for the sheets and 12 oz for the tape..you will use a lot of resin and it will take some time to completely wet through that heavy material, so be patient......make sure you have resin rollers, bubble rollers and plastic squeegees to spread the resin and remove the air pockets.....you will need to wait until each layer tacks a little before adding the next because of the weight of the glass.....it may want to slide on you being in a vertical position.....maybe you can use some type of plastic to clamp and hold the top of each sheet until it kicks.......but i wouldn't sweat it.....read the working and curing tables of your resin....you should have plenty of time....even overnight if you do a last layer late at night and continue the next morning.....all else fails, just let fully cure, sand with 80 grit, wipe with alcohol and keep going.

Bruce · #7 03-13-2011, 09:20 PM

I have nothing to ad but somebody has a truck exactly like mine. color and all. lol

CharlestonSC · #8 03-14-2011, 01:34 PM

That is my boat pulling truck. 06 F350

CharlestonSC · #9 03-14-2011, 01:54 PM

Update, dry fiting first layer of the transom waiting for epoxy to come in.
still have to do a bit more grinding to do.
Has a HF bisket joiner that I took the guard off of and that did a great job of getting the wood out.

mgarfield · #10 03-14-2011, 06:34 PM

I saw a good description by someone on a forum, might have been thehulltruth forum, where they wrote up a lengthy description on how to make the transom repair. I can no longer find it! Does anyone recall where that might be?