Boat Builder Central - Builder Forums

Some of you may be aware that while building my C17 build thread I bought an old glass boat to use as a donor craft. Basically I bought a trailer, motor, rodholders and battery, not so much the boat. I did plan to use the boat until my C17 is ready to go on the trailer at which point I'll either sell the hull for a $1 reserve auction, or take it to landfill.

Enough background. I was drilling holes in said donor boat to epoxy fill for a transducer. The wood is completely rotten through. Black and powdery at both the original screw holes I drilled out and the two new holes I intended to put the new transducer in to.

I don't want to spend $$$ and a lot of time to replace the entire transom for a boat that I'm only using a couple of years tops if I can help it. But I don't want it to be unsafe either. What can I do at this point to determine the risk?

1. drill more holes and see what the damage is?

2. Reinforce somehow as a quick fix?

3. Ignore and use? Will be mostly harbours and calm conditions.

Photos of holes and also some cracks in transom above. Transom about 5/16” of grp over ‘wood’.

Shitcan

Landfill? Eventually.

Drill holes to determine the extent of rot? How much until it's unsafe?

Stringers were redone about 5 years ago apparently.

I don't mind spending a smallish amount of money and time on it, but if it's a full replacement I'd probably pass on it. I'm thinking I'll check near some other places to see how much is gone.

Buy a good life raft.

The problem is the premise owt.

The reason me n Capeman responded universally in the NO is you cannot start out saying you want to use the boat with found rot in the transom and not want to put in the work or money for an adequate repair. It is a dangerous notion.

If you find rot in the transom; you must remove the inside lining of fiberglass in the area of the found rot and continue the removal of the liner until you have found all the rot. Unwise to shortcut the outside liner removal because the outside glass can be structurally compromised.

This may require holding the boat in shape and removal of the cap.

There is no such thing as a get by transom repair for calm water.

Those two guys in Florida in the Robalo perished at sea. We don't know for sure why, but it was likely one of two ways. The boat's transom may have broke off, filling the boat with water. Inadequate flotation foam in the Robalo finishes the job. The other way is the boat flips.

Anyhow, you either cut in and assess the damage or the boat is unsafe.

Sorry to say if it's already to the powder phase of rot it's way to far gone to save. If it were just wet wood you might be able to salvage some part of it. You could do a seacast fix, but it will still run you atleast $600 and it's time consuming.

silentneko wrote: ↑Thu Jan 14, 2021 9:54 am Sorry to say if it's already to the powder phase of rot it's way to far gone to save. If it were just wet wood you might be able to salvage some part of it. You could do a seacast fix, but it will still run you atleast $600 and it's time consuming.

There is no like button on the forum, but he is right. Powdered wood means the rot has been going on for awhile and reaches up into the wood pretty far which is why I advise the trashcan.

fallguy1000 wrote: ↑Thu Jan 14, 2021 10:36 am

silentneko wrote: ↑Thu Jan 14, 2021 9:54 am Sorry to say if it's already to the powder phase of rot it's way to far gone to save. If it were just wet wood you might be able to salvage some part of it. You could do a seacast fix, but it will still run you atleast $600 and it's time consuming.

There is no like button on the forum, but he is right. Powdered wood means the rot has been going on for awhile and reaches up into the wood pretty far which is why I advise the trashcan.

Understood all. I'll have a look at drilling away some from the inside and see just how pervasive the rot is. That costs nothing. If it's spread like you say then trashcan will be the solution. I don't mind cutting out and replacing wood, but a full transom replacement would be time and money better spent on the better boat. Regardless I'll keep it out of the water.

I must say that I feel pretty good about my own workmanship on the C17 after looking at an old (40 years) production boat. They look nice and shiny, but it's basically chopped glass laid up on pine with all sorts of sins hidden away.

I drilled another two holes from the inside this time. More to follow when I get on a PC.

Edit: OK I'm over my temporary state of denial.

I drilled two holes through the thin inside skin between the lower outboard mounting holes. Same story. Wet and soggy. No strength in the wood at all. There's any number of places where the water could have gotten in, not that it matters now.

Lets see if I have this right: To fix it I would need to remove the motor, aux bracket and wiring harness. Then support the transom, cut out completely from the inside including the back 400mm of the stringers and bottom, leaving the outside skin, Then epoxy in three of four layers of 9mm (3/8") plywood building it up to 20" from the current 15", tie it in to the sides with several layers of tape, glass over it, then glass in some braces to the stringers and hull bottom and redo the motorwell.

Is that the shape of it?