glass hull transom question...

[screwloose]

I looked at an older 15' Starcraft boat yesterday. The last owner replaced the deck and transom. He's a body guy that specializes in fiberglass truck body repair and trailers.
He did the job where he works. He's got pics of the whole repair. The deck looks fine, he removed the old wood, there's no flotation under the deck, just glass tubes or stringers.
He cut and fiberglassed the new 1/2" plywood with two layers of glass mat on both sides and resin, then glassed the new deck in place feathering the edges into the sides of the hull. That part looks great, it just needs to be painted.
On the transom, since the outer skin had torn away, he worked mostly from the outside. He cut away the area where the motor sat, he dug out all the old wood, ground the surrounding glass a bit and proceeded to lay up a new transom using both glass mat and recycled fiberglass trailer panels and mat. The result is a rock hard solid transom but I've just never heard of this being done before?
I'm sure it added some weight but I doubt its all that much on such a small transom. The solid glass area is about 57" x 15" x 1.5". He left the original corners intact and worked around them fitting the new panels and mat in behind the uncut sections of the outer skin. Other than the lack of an aluminum transom cap, you can't tell by looking at it and the 33hp motor on it don't budge.
My question is if this is an acceptable repair? Does it sound like a repair that will last? My concern I guess is the thickness of the entire glass panel now. I have little doubt about the rear panel being cut, he had no choice since the motor basically fell off tearing the transom rearward.
He also didn't try to hide any of the past repairs, if he didn't mention what was done or show me pics, I'd have never guessed it. I'd probably have assumed it was a poured transom.

 

[jbcurt00]

Re: glass hull transom question...

You need to post some pix for a better assessment of whether or not it was a 'sound' & seaworthy repair.

A 33hp motor is certainly less weight & torque then a larger motor, but it still has weight & exerts a force against the transom. You'll want to be more then moderately confident the repair can stand up to the forces the motor will exert while under way.

 

[screwloose]

Re: glass hull transom question...

I don't have any pics, I can take a few phone pics but I'm not sure how much that'll show. The boat looks basically all bone stock right now, you can't tell anything was done to it other than its been resprayed below the rub rail and there's no aluminum cap on the transom, its just smoothed over and painted. He had no problems demonstrating that the transom has no movement but standing on the lower unit and bouncing up and down, the thing don't flex even a fraction of an inch. He's been using it for while now himself but got a nasty ticket for using a gas engine in freshwater here.

The pics he's got are Polaroid photos hanging on his tool box at the body shop where he works and where he stores the boat. The pics show the boat with the transom wood removed and most of the rear transom skin cut away, with about 6" left intact across the bottom and down both sides. He ground the edges back and feathered them about 4" or so and laid up the final layer of mat and resin once he got to that point. I think the repair was done that way since he didn't know any other way, and didn't want to put wood back. My concern isn't whether its strong, I'm more concerned whether or not a 1 1/2" build up of glass and resin will survive over time or will it crack or separate?
His job where he works is fixing fiberglass hoods and crash damage in a truck body shop. He's been there for 30+ years.

When he first told me the transom was all fiberglass what came to mind was him mixing up a bucket of resin and chopped glass and pouring it in from the top until I saw the pics.

I don't like the idea of him cutting the outer transom panel vs. working from the inside but it was already torn from how it failed. the end result looks fine, if he didn't tell me what he did, I'd have never gave it a second thought and just assumed that someone poured a new transom with Seacast. What tipped me off was the missing transom cap. He's got the old aluminum transom cap but its eaten away where the motor sits so he left it off.
One thing I wish he did was make the transom 20" not the original 15". It would be far more usable boat with more freeboard in the stern. With the cable steering, the transom sides are pretty open, not sealed off, so too much water in the splashwell in rough water and its going into the bilge pretty fast. That's a design of the boat, not his doing.

I figure that I could make up a panel to attach to fill the opening a bit better to prevent any following seas from getting into the splash well. Even if I just raise it two or three inches it'll be a bit safer. If not a rubber or plastic panel, maybe a flared edge to deflect water. I could cut a 1/4 length of 6" PVC pipe and attach it to the top of the transom to deflect water in the event of a big wake or rough water. I guess more for peace of mind than anything else.
With no one in the boat it draws only a few inches of water even at the stern with the 33hp on it. If I left the 33hp, I'd move the batter up front, its not needed for the manual start motor and only powers the running lights, dash lights, and fish finder. If I change the motor, I'd add a separate starting battery for the motor.

I would most likely remove the 33hp and hang a newer 20hp Mercury I already have, I don't need much power its just a boat to fish and crab with. I just don't want the transom falling off while I'm out on the river here.

The boat is white below the rub rail, blue gel coat above. The title says its a 1960 Starcraft FG. The beam width at the windshield measures 71" and the transom measured about 61" across the very top rub rail to rub rail. Its a smooth glass hull, not the type that looks like siding.
He's also got a glass three panel windshield he intended to use on it that comes with it, but the boat has a decent looing original plexiglass windshield on it now. He just wanted a glass windshield I guess. For me, glass is nice but my thinking is plexiglass is much lighter. Especially if I were to hang a smaller motor.

 

[jigngrub]

Re: glass hull transom question...

, there's no flotation under the deck, just glass tubes or stringers.

This is bad!

There's 2 reasons floatation foam is installed in fiberglass boats.

 

[Woodonglass]

Re: glass hull transom question...

How much? How Old? I'm Skeptical.

 

[vintageglass]

Re: glass hull transom question...

From your description, the boat sounds like an old Voyager model. Those did not have flotation foam. The 'stringers' were mearly hollow fiberglass formed over cardboard tubes attached to the outer hull. The deck just sat on top of them.

I would think that the only real drawback to a solid glass transom may be weight, from a strength aspect, I'd say its far stronger than wood or anything else assuming each layer was laid up correctly. Since that's a relatively small transom, the added weight would be negligible.
I agree though, when he did the transom work, that would have been the ideal time to raise the transom height to 20" especially if he was eliminating the aluminum cap. The aluminum cap was mearly there to keep water out of the top of the transom and to cover the seam left from where the top cap of the hull met the lower hull along the outer edge. If he did the whole transom out of glass, chances are the two halves, or at least the transom and splashwell are now permanently attached.

Those were good boats, they rivaled aluminum models when it came to weight. The 1960 brochure lists that hull at only 418 lbs.
The original seating was either one or two bench seats. The rear seat across the back was optional. The front seat attached to tabs on each side. Most people tossed the original seat in favor of back to back or pedestal seats over the years. The original seat meant you had to climb over the back of the seat to drive the boat. They were also flat bottom boats, they rode OK but could be a big harsh in bigger water. They would go places that a V hull wouldn't think of though.

I had one a few years ago with a 25hp motor, it did just fine. In fact it ran almost as fast with the modern 25hp on it than it did with the older 40hp it came with. It did about 25 mph with the original 40hp, and ran 23 mph with the newer 25hp on it, and I gained several inches of freeboard. Keep in mind that back when that boat was new most 25hp motors weighed the same as most 40hp models.

With a small, light motor any concerns about transom durability are far less, but from the sound of what you describe, that transom may be pretty much bomb proof. The best part being that it'll never again rot away or fail. I did know one guy who did a Seacast transom and to save the cost of an additional bucket of Seacast, he cut up an old boat, cutting strips of old fiberglass which he used to fill the transom as he poured the Seacast, sort of like re-bar in concrete. Since Seacast is basically a polyester mix, I'm sure it only made the transom stronger.
Another reason that most boats probably don't have solid glass transoms is cost, I can't imagine what the materials would tally up to if you had build one that way from scratch. I can see using a whole roll of mat and gallons of resin to finish the job. By using preformed glass panels like he did, he in effect made a structure far stronger than any wood transom.

 

[screwloose]

Re: glass hull transom question...

I found this online: http://www.flickr.com/photos/starcraftbrochures/3879241667/in/set-72157622086586835/lightbox/
The boat I'm looking at is the same but with a blue top and two pedestal seats.
The seller only wants $1200 for it and its a running boat. I don't see where it could have had any flotation beneath the deck, there's no room. The 'stringers' are only a few inches tall and there's only 4 of them. The 'stringers' are formed as part of the hull, there's no wood inside. They appear to have been formed over a mold. The deck stops just beyond where the splashwell starts, the battery and fuel tank sit on the inside of the outer hull. You can see clearly how the boat is made. I've looked at a few other boats with the same set up.
I'm pretty much thinking that for the price its well worth the chance. I'll just wear a life vest I guess till I come to trust the repair.
If my 300lbs jumping on the lower unit don't move the transom, I doubt if its going anywhere.
Also, with the smaller motor, its not under nearly as much load.

I don't plan to take it far, just in the river and a few back bays and creeks for crabbing. If it sinks in most of the places I go, it'll only be in a few feet of water. If I were looking to go fast or hang a big motor on it I'd be more concerned. Maybe only after it proves itself for a few years I'll add a bigger motor.