Transom and Stringer Repair Advice

[Pierce89]

Good morning,

I am restoring a '97 Maycraft 1900 as a winter project and had a couple questions I'm hoping someone could help with. I almost have all transom wood exposed and ready to cut back stringers.

1. Either Maycraft or the original owner drilled into the stringers many times for the deck before fiberglassing over it. The outside stringers look OK besides the screws in them. The inside ones look more rotten and split. Has anyone reused the old stringers by grinding down the fiberglass and laying 2 layers of 1708 over them?

I've read some people use foam for stringers and fiberglass over them, which is why I'm thinking I can reuse the outside ones as templates for new fiberglass regardless of the wood inside. The inside ones I'd cut the wood a little taller to account for the 2 additional 1708 layers on outside stringers.


2. Where to make the cut for the transom cap to make it easiest for later to make everything uniform. Cut on inside edge of boat leaving the top of transom cap intact, or cut on outside edge of boat to remove transom cap. I may be overthinking this part

Thanks for any advice

 

[tpenfield]

Get rid of all the old/rotten/wet stuff. Keeping it there does you no good, even if you glass over it.

Yes on the foam core stringers. It is pricey, but worth it IMO. Divinycell is a structural foam commonly used for stringers.

Not sure what you are asking about the transom cap . . . looks like you already go it exposed.

 

[Scott Danforth]

if your boat had wood, redo it in wood

if you want to go without wood, use coosa or other.

if you want to go over foam, talk to a naval architect for proper layup. you may have to go with 4 layers of 1704 minimum

no use attempting to keep the old stringers

 

[KJM]

Wet rotten stringers would add a lot of unnecessary weight, you gone that far, may as well strip her out and rebuild properly.

 

[tank1949]

Wet rotten stringers would add a lot of unnecessary weight, you gone that far, may as well strip her out and rebuild properly.

There is great advice above!!!!! U may want to invest in air tools and a compressor. I have restored 2 boats built with crap and not sealed well. The air chisels work great to quickly eliminate crud and rot. However, access below deck make require cutting deck out to access forward stringer material. I had to on a Proline. Once a new and clean stringer cavity is created, u can decide on the best options. LET IT DRY!!!!! The real work is removing ALL METAL and storing before attempting to replace a transom. If you have rotten stringers, then chances are ur transom needs replacing. Outboards are easier. I/Os are a nightmare. U may have to pull heavy V8s and store them. I stored 2 in my cockpit area using standard cheap Harbour freight tools.

 

[Pierce89]

Thanks for the responses, I'll take the advice and rebuild the stringers from scratch. I don't have the boat in a cradle so I'll cut a foot off from each stringer, replace transom, then remove and build each stringer one by one. This is my 3rd restoration and I do have the compressor/pneumatic tools. The idea to keep those outer stringers was just because I remember it was quite difficult to set the stringers in poly resin peanut butter, have them stay vertical while drying, and have them all level for the deck. Was hoping to avoid having to do another 2 if it wasn't necessary!

For the transom cap, I left the top of the cap on and haven't cut anymore yet. I wanted to see if anyone had advice on best way to cut to make it easier later. I can't find any videos showing when after the new transom is tabbed in, wrapping 1708 over the transom to create a new cap, then gelcoat, but make everything blend in. In my head, once I wrap 1708 over the transom there will be a bulge on the outer skin and I can't make it uniform to the exterior.

 

[KJM]

Thanks for the responses, I'll take the advice and rebuild the stringers from scratch. I don't have the boat in a cradle so I'll cut a foot off from each stringer, replace transom, then remove and build each stringer one by one. This is my 3rd restoration and I do have the compressor/pneumatic tools. The idea to keep those outer stringers was just because I remember it was quite difficult to set the stringers in poly resin peanut butter, have them stay vertical while drying, and have them all level for the deck. Was hoping to avoid having to do another 2 if it wasn't necessary!

For the transom cap, I left the top of the cap on and haven't cut anymore yet. I wanted to see if anyone had advice on best way to cut to make it easier later. I can't find any videos showing when after the new transom is tabbed in, wrapping 1708 over the transom to create a new cap, then gelcoat, but make everything blend in. In my head, once I wrap 1708 over the transom there will be a bulge on the outer skin and I can't make it uniform to the exterior.

What I did was not wrap 1708 over the top. At the cut down part for the outboard, I just used PB to level and smooth the top surface off. Its tabbed in to the sides, the stringers and the floor. As well there is a splash well just below the area where the motor mounts thats also tabbed in. That should be enough to hold it all solid, at least it has for the last 2 years since I did it! I used "thermo lite" board for the core and stringers so I won't have to worry about rot anymore.

 

[Pierce89]

What I did was not wrap 1708 over the top. At the cut down part for the outboard, I just used PB to level and smooth the top surface off. Its tabbed in to the sides, the stringers and the floor. As well there is a splash well just below the area where the motor mounts thats also tabbed in. That should be enough to hold it all solid, at least it has for the last 2 years since I did it! I used "thermo lite" board for the core and stringers so I won't have to worry about rot anymore.

This is a really good idea! Thanks for sharing. I will do the same