Transom- Should I fix it or not?

[Curious]

I would build it from coosa board or marine plywood layered with biaxle then tab it in.

Capt Matt

I haven't ruled this out yet either, although I am leaning toward the pour method.  Would I still cut the back skin off, clean out the rotten wood, build the transom up with the coosa or wood, put the rear skin back on and glass it in?  If I did this, how do you fasten the new wood or coosa to the front and rear skin of the transom?  Thanks for the input.

[Curious]

Fitz, Seabob, etc.:

That transom crack in "Curious"'s first photo is in sort of a strange place, no?  It looks like the outboard "face" is pushed out, and perhaps the inside face too.  I'm wondering what would cause that?   Wood swelling?

If it's getting re-built anyway, it doesn't matter, but I wish I could see more photos of it.

I'm pretty sure it's wood swelling because it got wet.  It could also be that it got wet, swelled, then froze and expanded as well, (I live in the Northest).  Some on this site have mentioned that it is probably just the top cap separating from the transom which seems to happen on occassion as well.  I was almost going to just seal it and mount the motor until I saw how much black mud and moisture came out of the screw holes at the bottom of the transom that I mentioned.  At any rate, here's a couple more pics:

[Curious]

Fitz, Seabob, etc.:

That transom crack in "Curious"'s first photo is in sort of a strange place, no?  It looks like the outboard "face" is pushed out, and perhaps the inside face too.  I'm wondering what would cause that?   Wood swelling?

If it's getting re-built anyway, it doesn't matter, but I wish I could see more photos of it.

I'm pretty sure it's wood swelling because it got wet.  It could also be that it got wet, swelled, then froze and expanded as well, (I live in the Northest).  Some on this site have mentioned that it is probably just the top cap separating from the transom which seems to happen on occassion as well.  I was almost going to just seal it and mount the motor until I saw how much black mud and moisture came out of the screw holes at the bottom of the transom that I mentioned.  At any rate, here's a couple more pics:





You'll notice the main crack on the starboard vertical side in the first pic and then there is another one just to the right of where the motor mounts to the transom.  By the way, I think this cap area has had some repair work done to it before, you can see minor imperfections in the gelcoat that looks like its been fixed before.  Probably should have mentioned that.

[fitz73222]

Fitz, Seabob, etc.:

That transom crack in "Curious"'s first photo is in sort of a strange place, no?  It looks like the outboard "face" is pushed out, and perhaps the inside face too.  I'm wondering what would cause that?   Wood swelling?

If it's getting re-built anyway, it doesn't matter, but I wish I could see more photos of it.

I'm pretty sure it's wood swelling because it got wet.  It could also be that it got wet, swelled, then froze and expanded as well, (I live in the Northest).  Some on this site have mentioned that it is probably just the top cap separating from the transom which seems to happen on occassion as well.  I was almost going to just seal it and mount the motor until I saw how much black mud and moisture came out of the screw holes at the bottom of the transom that I mentioned.  At any rate, here's a couple more pics:





You'll notice the main crack on the starboard vertical side in the first pic and then there is another one just to the right of where the motor mounts to the transom.  By the way, I think this cap area has had some repair work done to it before, you can see minor imperfections in the gelcoat that looks like its been fixed before.  Probably should have mentioned that.

The wood core supports the fiberglass and gelcoat. When the core rots, the support for the fiberglass and gelcoat is gone and it begins to collapse and crack. There is not much to read into this; thats pretty much whats going on. You need a transom. You can either pour a new one or cut the glass from the INSIDE and dig out the core and replace with the material of choice. Cutting the outside of the transom to decore is a carryover from wood boat days and will cause you many hours of fairing in the new transom and less strenght in my opinion.

[gran398]

Absolutely, from the inside, leaving the rear skin on. All of what fitz has just mentioned, plus, the hull stays more rigid.
(Its attached to the stern-most hull sides)

An added benefit: you keep intact the stamped Aqua hull #'s.

[Curious]

Would you guys make my mind up for me, for cryin' out loud!   Now you've got me thinking that the best method, structurally, is to remove the top cap, leave the inner and outer skin in place, grind out the rot, pour, and recap!  Again, keep in mind that I don't want to get involved in a deck off, refoam the stringers, etc, etc complete rebuild.  Anyways, I thought I had this all figured out....

[GoneFission]

Poured transom results are generally pretty good.  Probably less work than a full recore.  Do your prep work well and you are likely to get good results.  Some manufacturers actually advertise a poured transom as an advantage.  

Survey says...   !!!

[slvrlng]

If the core was as wet as you said I would not try to dig it out with both skins intact. You can still pour it just cut out the inside, grind out the old and fix any delams. Then build a dam out of melanine coated with release wax and PVA. With the inside skin gone you can repair any issues with the outer skin much more easily. Then tab the sole back to your pour.

[fitz73222]

I thought melanine was what the Chinese substituted for protein in baby formula that was some sort of glue? Does it work for transom repair also?

[gran398]

Careful here bro...you could be guilty of... a "thread-morph" :!:

 

Like yes like yes you thank. Yes! Melanine yes! Too for good baby!

[slvrlng]

Sorry spellcheck didn't pick it up!  MelaMine.

[Capt Matt]

Poured is going to be the quickest method,  Its all in the prep work
I went all out cutting out the old transom when I did mine. I knew I would be hanging my motor on a porta bracket and it would need to be crazy strong.
Capt Matt

[marco]

Curious,
IMHO and not so HO I'd go with a poured SEACAST transom. I did my 19'6 4 years ago with Seacast, and the transom is rock solid. I cut the rear skin off so I could do a real good job of cleaning out the old plywood. I added a layer of mate and roving to the inside of the skin I cut off and to the inside of the inner transom to strengthen it. Used a 5/8 plywood form and screwed the outside skin to it then screwed it to the back of the boat. This held everything in place and in position for the Seacast pour. It took 2) 5 gal buckets of Seacast to do my transom. I put a mate cap on the top of the transome while the Seacast was still "wet". Had to actually mix up a little resin to fully wet it out. Let the whole thing cure up for a day. Then I made a form that matched the top of the transom and filled that (about 1/2-5/8 ") with 1/4 fileings and resin.
You'll have to grind back about 4 inches either side of the cut line on the rear skin and glass the seam in.
Then there is plenty of sanding to do if you want it to look good. I sprayed gelcoat and sanded it to 1200 grit then buffed it out. The project is a fair amount of work about 40-50 hours but I think it was well worth the effort.
BTW you use all polyester resin when working with seacast, no epoxy.
I posted some pictures of the finished job.
http://classicaquasport.com/smf/index.php?topic=7063.0
Good luck