sea cast

[gw204]

While we are the subject....

Has any one used Coosa board in there transom rebuilds?

Any stories pro or con about the stuff?

The only con I have heard about Coosa was that in can "gas out" (or something like that) and cause bubbles in the glass that you lay over it. This info. came from a very reputable builder on the eastern shore of MD that told me they have seen this first hand.

That being said, I've talked to a few shops about different coring materials for the transom of my Mako and each and every one of them have told me to us marine ply.

 

[TBone]

Thats interesting, Ive never seen the the stuff (Coosa)in person, is it

porus like "foam"?

I agree ply is tried and true when kept dry, but the problem I cant over look is that

it rots, no matter how well it was made there is alwasys a chance of

water intrution, even from the slightest defect, or just from age.

And once its starts thats it.

People are always replacing "plywood" trasnoms that have rotted out.

Heck, if i was in the business of replacing transoms, I would want them

all to be made from ply.

Im not saying that a well mantained plywood transom wont last, its just

there are so many that dont.

My reseach yet still has not produced any true instances where a Seacast

transom had to be replaced.

And yes I have found some of reto-sites that say they use it in their post.

Im not totally sold on the stuff, but I have yet to find any thing that says

it isnt any good other than "feelings".

Gradyfish 22:
"I do agree the product looks neat and in the future it might be great,
but I'd be a bit leary of it honestly. It might be ok for a fix for
a year or two but I would not recommend it for a lifetime fix."

Like I said before, not being wise, just looking for info, My question is why

you say that, have you had, or know someone that has had experirece with it?

From what I have learned people have been using the stuff over 25+ years.

You would think if there was bad experiences with it people would shout?

Did you guys check out that link with the drop test?

That was interesting....

Like I said Im not sold on the stuff but I cant find anything bad about it.

 

[Grog]

The invisionboatworks one looks decent. According to the picture, they remove the skin and get the old wood out. That's a lot better than the drop in the chainsaw method posted on one of the other sites.

 

[NOTHING ELSE MATTERS]

The transom of my skiff is made with coosa. So far no complains. I don't think i saw a boatbuilder company using sea cast at their transoms. But i would also say plywood is the best bet, tried and prooven for a lot of years, just seal it much better than the boat manufacturers do, it will last for a life time. Just my two pennies.

 

[gw204]

water intrution, even from the slightest defect, or just from age.

Wood doesn't rot just because it gets old. The floor in my 1981 Mako is made of plywood and it is rock solid and completely dry. I know that for a fact as I had to cut the aft portion of the deck out to do the transom. The floor was done right, the transom wasn't....that's the difference.

That's why so many Grady's have problems with transom, stringer and/or deck rot. The builder and many owners don't take the necessary precautions to keep the wood dry.

 

[TBone]

water intrution, even from the slightest defect, or just from age.

Wood doesn't rot just because it gets old. .

What I meant there was the Fiberglass sealing it in getting old, wear and tear over time, age, on the fiberglass of the transom letting the water get in.

And like I said before, Im not saying that plywood is not the way to go,

Im just trying to find some EVIDENCE that Seacast IS NOT the way to go,

other than that of tradition.

 

[BobP]

One of the web sites showed a job where the equivalent of stripping off the outer skin, removing all the wood clean, I guess prepping the surface of both skins, then replacing the outer skin, last followed by pourind in the seacast. So it saves the cutting, fitting out, and clamping of plywood sections. Similar materials costs, somewhat less labor. Cutting off the outer skin seems like the easiest way to assure the surface on both inner sides can be prep'd properly, or getting a long handled chisel and pole sanding pad, especially for the deeper transoms. Shallow transoms are easier enough to get into the bottom reaches from above.

Can I take it Seacast is similar to silica thickened polyester resin with chopped glass added ?

When using plywood it makes sense to add glass between layers, per Dunk method. Then the new plywood and glass sandwich is going to be way stronger than the original plywood transom.

I expect seacast to be of similar weight to plywood (?)

I wonder if seacast will warp over time and load like starboard does? vs. same thickness of marine plywood layered with glass in between?

Gotta keep water out of the transom, all transoms, if water can find its way between the skin and seacast, better not plan to keep the boat in freezing climates.

 

[boxer123]

sorry guys i wanna give an update on yhe seacast project but it needs to be 65 or above no luck with that in ny but iam looking to get the boat inside so when i do so i will have some pics

 

[gradyfish22]

water intrution, even from the slightest defect, or just from age.

Wood doesn't rot just because it gets old. .

What I meant there was the Fiberglass sealing it in getting old, wear and tear over time, age, on the fiberglass of the transom letting the water get in.

And like I said before, Im not saying that plywood is not the way to go,

Im just trying to find some EVIDENCE that Seacast IS NOT the way to go,

other than that of tradition.

Fiberglass doesnt get old and wear, poor maintenance or poor layup by the builder are causes of problems down the road. If the hull uses the right skins and mat layup it should be able to take a beating for years and years and never show age, the problem is too many builders try to build lighter boats and cut corners and push the limits of "modern" materials for their time. You can either lay a boat up where it is like a tank, or make it strong enough for most conditons, a Grady is laid up fairly well so it should be able to take a beating and last for years. I do see that for some years they did have issues with transom and stringer layup...probably an issue with quality control and allowing air bubbles in the resin and glass which severly weakens the glass. Where I work we sand those spots out if they occur which is rare and reglass them over to ensure strength and wuality and a long lasting hull. If the job is done right with wood and fiberglass there is no need to worry. As some have mentioned, wood does not rot from age it rots from moisture. I like Bobp's thought's and he knows his stuff as well, prepping both sides of fiberglass is the only way to get good adhersion and for the job to last long.
As asked above, no I have not worked with seacast and never plan to. I've seen 35 year old boats with wood transoms in them come back to our factory after years of abuse and have no structural issues, the ones that did have issues were from poor maintenance or hurricane damage...or idiots driving over jeeties...boy I've seen that more then a few times.

 

[BobP]

Boxer, just build a tent around the transom and get a couple of electric or propane heaters in there.

It's probably a viscosity issue.

Even if you are using plywood and cloth insstead with epoxy resin to rebuild the transom, the resin viscosity gets thick and takes much longer to pump, mix, and wet out wood and cloth with. Big difference when it's above 70 deg.

I expect Seacast has to pour readily to push out the air pocket voids. Further, you may want to check with the vendor to see if making up the mix batch indoor at 80 deg. is advisable.

 

[TBone]

Boxer, any updates on how you transom is coming?

 

[BobP]

Tbone, do you intend to do the job yourself or hire out?

If you are a DIYer, there is a lot of prep work you need to doing irrespective of which way you go later on material choice. Let us know, and have you worked laying up glass before ?

As any good prefessional painter would say, 90% of the work is in the preping.

 

[TBone]

typo

 

[TBone]

Bob, yup, Im gonig at her my self! With full confidence.

I just got most of the supplies to start the glassing I need to do.

I had a nice long talk with my glass supplier and he gave my great instructions and tips.

Which is why I like to get my stuff in person. You may save on the internet, but the things you can get for

free from face to face interactions in instances like this, out weigh any discount.

It worked out quite well because I have been going to this guy for years when I was restoring my wooden Gradys.

He had all the fasteners I needed to use (silicon bronze). As well as the paint and varnishes I used (Epiphanes).

Ive always gone to him, so when it came time to get glass supplies, it was no problem for him to take

a few hours out of his day to look at my pics and hear my plans, then give me step by step instrutions and tips on what to

do. Best a of all, he said if you have any troubles just give me a call.

I also dicussed the the Sea cast with him, (he does not sell it) and he says it is a great product.

He personally knew of people using it and have had great results.

I also told him how the original was transom was set up, and he said Grady makes such a great hull

I don't know why in the heck they do that with their transoms, your not the first one in here getting supplies for a Grady transom.

So next is to start grinding away and get her all prepped. All the wood is out.

Im going to glass back downs the stringers and seal them over the top. The only have resin and gelcoat from factory.

They way he told me to do it, this transom will be strong as a tank.

I have some more pics, and I plan on starting a new thread on the project.

I will keep you all updated.

It will be my first glass job, but Im confident.
Thanks,

Tony L.

 

[BobP]

Glad to hear it is working out.

Nothing better than to have someone knowledgable guide you on the first one.

Besides personal gradification, your next season's gas bill will be on the house!