Transom replacement.

[PeteyD]

Hi Iboats first timer here, been reading a lot of topics, some very helpful people here. Ive been collecting info for my project all over the net but thought specific advice would be a good idea.

I have a 14 ft Larivee with a bad transom, flex's, cracks, even water draining out the bottom while installing a new fish finder, great. I started tearing out the wood while drinking beers, which yes is a great idea. I was going to go through the back and top, but have read cutting the back of the hull is not desirable. I would go in through the front but seem to figure its more work to cut out the benches on either side and the angled structure coming up to the transom from the floor, which i figure is a stringer, not to keen on cutting through a stringer to transom joint. I may have cut away to much inner and outter skin already making things more difficult. Any advice to move from this point would be great thanks guys.

 

[Woodonglass]

Re: Transom replacement.

Welcome to iBoats!
If you want to do it right, you're gunna need to cut the boxes back at least 10 -12 inches. You will also need to cut the decking back that far as well to gain full access to the entirety of the transom. I suspect when you start cutting you will find more rot. If the transom is this bad there's a very good possibility that the stringers are rotten as well. You will need to decide just how far you want to go with her.

 

[PeteyD]

Re: Transom replacement.

You mean cut an opening into the boxes 10-12 inches up from the transom and remove that 10-12 inches of material to access the transom? I would need to cut flush with the transom inner skin correct? This boat seems odd i just tore up a peice of decking a foot or so up from the transom which is only a thin piece glass. You can see in the picture undernearth the deck is just a wet peice of plywood. The stringers on the left and right side of the pictures dont appear to have any defined core material it just seems to go into the plywood.

 

[ondarvr]

Re: Transom replacement.

The problem is as WOG said, if the transom is rotten there is a very good chance the stringers are too, that is if they're wood. The boxes are probably framed in wood and may be rotten also.

It can be done from the outside, but unless you know for sure there is no rot elswhere you will typically end up cutting out out everything on inside too, which makes it even more work and money.

 

[BonairII]

Re: Transom replacement.

Before tearing into your boat any further.....do some reading on the hell that you are likely walking into.

From your description, your boat is probably completely rotten(transom, stringers, waterlogged foam etc). LOTS of time/money will be required to rebuild your boat.

It'll much cheaper/easier to ditch your boat and start over.

If you insist on restoring it....you're in the right place. There are many resto pros here that will walk you through the process.

 

[Woodonglass]

Re: Transom replacement.

Your Stringers have completey rotted away. IMHO you will need to fully gut your boat and do a total restore. It's your decision on whether or not she's worth the time, money and effort. A Guess-ti-mate would be $1,500, 150 hours and Lots of ITCHY YUCKY work. Up to you!!!

 

[PeteyD]

Re: Transom replacement.

Well its hard to give up on this since ive gotten myself into this mess, dont wanna turn tail and run. I have read extensively all over the net and here on this forum about the hell that is boat restoration, But buying a replacement boat is also expensive, i think im to stubborn to give up.. so im gonna go start grinding now.

 

[BigLee324]

Re: Transom replacement.

if you're gonna grind, get your self a tyvek suit and a full face respirator, the fiber glass goes eveywhere.
Be sure to use talcum powder on your skin prior to suiting up, it will cut down on the itch later.
proper protection now will save you alot of problems .

 

[GT1000000]

Re: Transom replacement.

Welcome to the drydock PeteyD,

You will get all the information here to do it the right way...

My first suggestion is to do a lot of reading, to get familiar with what you are up against...

You can start with these two...
http://forums.iboats.com/showthread.php?t=234392
http://forums.iboats.com/showthread.php?t=510077

Post up a ton of pictures...Here's how...
http://forums.iboats.com/showthread.php?t=410147

Get the proper safety gear...fiberglass dust is very unforgiving...

And most importantly...Stock up on lots and lots of Beer!!!

Best of luck and before you know it you will end up with a boat that looks like mine...

Have Fun!

 

[BonairII]

Re: Transom replacement.

Well its hard to give up on this since ive gotten myself into this mess, dont wanna turn tail and run.

There's no shame in NOT restoring it. How much money do you already have into the boat? Throwing good money after bad doesn't make much sense.

If you feel that you'll have a boat that you'll keep for years and years(and be happy about it) after the restoration than go ahead and go for it.......BUT

if you're doing it just because you're stubborn, you'll be miserable during the entire resto process.

"Discretion is the better part of Valor" - William Shakespeare

 

[PeteyD]

Re: Transom replacement.

Not miserable at all. Demo is going well, just a quick question about the plywood for the transom itself. Its hard to measure the original width of the transom, at the best spot with the least amount of delamination i can measure about 1 and 3/4 inch with the laminate included, but other areas where the plys have come apart is wider, ive also counted 9 layers of ply total which seems odd, 1/2 inch ply has 4 layups, 5/8 5 layups and 3/4 6 layups. Anyway just wondering if im good to use two half inch plys? ive read that a slightly smaller replacement core is better than a larger?

Also for protection im using a 3M half face mask with P100 cartridge, liberated from work hehe(ive heard these are suitable for fiberglass) heavy glasses, and coveralls.

 

[Woodonglass]

Re: Transom replacement.

I'd go back with either two 3/4" lams or 2 -1/2" lams with a 3/4" piece sandwiched between the two. 13/4" is a fairly standard thickness for a boat transom. As for the plys, different mfg's use different # of plys. Marine Grade usually has more plys than construction grade so you can't really go by the # of plys.

 

[PeteyD]

Re: Transom replacement.

Well the demo is going swimmingly, 60 grit sanding discs is my new favorite thing. Single stringer up the middle with what appeared to be a piece of plywood up the middle on top of the center stringer, with a thin glass layer as the floor, looking at materials and next steps. and thoughts or comments? Thanks guys.

 

[PeteyD]

Re: Transom replacement.

Easy question, il be sealing the transom and stringer with csm, when it comes to 1708 does it matter what side goes down ? the matt side or what? Thanks.

 

[Woodonglass]

Re: Transom replacement.

Matt side down. Make sure and coat the wood with resin first. When it tacks up roll on some more and apply the CSM. Just use enough to wet it out and make it go clear. Don't over roll it and lift the glas fibers. Use a bubble roller to make sure you don't get any air bubbles.

 

[PeteyD]

Re: Transom replacement.

Thanks for the reply Wood, so I guess i need to invest in a better clamping method. Anyways I had to cut out the front part of the bow under the casting deck to get to the front of the stringer. Took out a bunch of foam it was glued i guess on the underside of the deck. Whats the deal with this foam? why is it there should I replace it? thanks.

 

[PeteyD]

Re: Transom replacement.

So the transom is ready to go. Just double checking some things, resin with one 1.5 csm layer done first? Should I drill holes to allow pb to ooze out? What kind of mixing ratios should I use for the resin, cabosil and csm strands? I was going to tab in two layers with 1708. Been reading that csm should be used? Also what can I use to thin gelcoat for use in a spray gun? Thanks.

 

[GT1000000]

Re: Transom replacement.

The foam is there for floatation, in case the boat gets swamped...it is a safety feature and should be replaced...

Check out 'woodonglass' signature for a layup schedule for the transom...

Drilling the holes is a good idea, some drill through the outer hull skin, while others drill through the transom plates...which act sort of like PB nails...they also allow the PB someplace to migrate to and hopefully prevent any air pockets.

Don't forget to have a good way of clamping the transom plates solidly to the hull skin and do a rehearsal or two with an assistant, to get familiar with the procedure and timing...once you mix up the PB, you will only have about 15 minutes of working time...

BTW, pre-prep several small [quart] batches at a time without adding the MEK-P, have it pre-measured and add it to the batch as needed...if you make one huge batch, the heat generated will kick of the batch very quickly...one trick that has been used is to pre-cool the resin to fool it into kicking off slower...

Can't remember exactly what part of 'friscoboater's' or 'oops!' threads show the making of PB, but you should be able to find them...

Also plan on using the PB that oozes out as some of the filleting...

 

[PeteyD]

Re: Transom replacement.

For pb I have cabosil and csm fibers. I was under the impression this was all that's needed to mix pb. Do I need the glass bubbles if I'm not sanding?

 

[GT1000000]

Re: Transom replacement.

For pb I have cabosil and csm fibers. I was under the impression this was all that's needed to mix pb. Do I need the glass bubbles if I'm not sanding?

Nope, don't need the bubbles...