1975 Steury 15' Tri-hull Restoration

[boatlex]

Hello everyone!

I've been reading through all these great restoration threads on this forum, and decided to sign up and start a thread for my project. I hope mine turns out half as nice as the ones on here! This is (sort of ) my first boat restoration, I started one a few yrs ago but then ran into issues getting the title. I've done tons of research so I think I know what I'm getting myself into.

Since everyone loves pics, I'll start out with a few before I start asking questions...

I forgot to take some real "before" shots. But all I've done in these is remove the rub rail and set the motor on a stand.






Alex

 

[boatlex]

The backstory:

My buddy gave me this boat. He's owned it since he was 15. The transom is mush, the floors are mush (at least what's left of them), and it's full of soggy foam.

I hear these tri-hulls are very stable and as such are well suited to a bass boat style raised deck. So my tentative plan is to build up casting decks at the bow & stern (storage underneath), remove the console & livewell, and convert to tiller steering.

Sometimes it'll just be me and a friend fishing, but sometimes the whole family (3 kids). And it's a small boat. So I need lots of seating that won't get in the way. The rear is easy - I've seen lots of examples of seats that fold flat to become the casting deck. But the bow is a bit trickier. If I did it the same way, the seats would face backwards. Still trying to come up with a better idea.

Here's a shot from the front showing the toilet - I mean, flower pot - I mean, livewell. Starting to remove soaked foam.


Bow foam removed! You can see here that from the factory the boat came with a raised platform - I will just be raising it even higher

 

[boatlex]

The engine...

Although it hasn't been run in almost 10 years, I believe the powerhead to be good. It turns over smoothly by hand, and has compression (though I haven't actually measured it yet). Unfortunately the lower unit is totally locked up. The prop seal was completely shot, so it was probably stored full of river water. Does anybody know which lower units are compatible? It's a '75 "fifty sizzler". The lower unit it has on it right now came from a 70hp engine. I'll post some pics of the lower unit later on.

I'm also wondering about tiller conversion. Looks like they didn't make a tiller kit for this particular motor, but I've seen several online that look like they might work with a bit of modification (a little adapter plate to mount it). They sure are expensive though! Is there anything else I need to do the modification? Do I need something to add friction to the steering?

Here is a pic of how the remote steering connects to this motor:

 

[Woodonglass]

Uhmmm, speaking from experience, the time, effort, and money you'll spend on making this a viable fishing boat, especially since the motor is a total "Unknown"...IMHO would be much better spent looking for a boat in better condition. This one at a minimum will cost $1,000 to get back on the water. You can find a better one for less. :joyous:

 

[boatlex]

Yep. I'm sure I could find a better one. But I like fixing things, hate throwing things out, and I've got it in my head to do this now, so I'm gonna push on. I'm stubborn like that

 

[Woodonglass]

Alrighty then!!! Just wanted you to be aware of the costs. Lot's of fiberglass work to be done, etc. My guesstimate will be ove 100 man hours of work, and $1K in costs IF you can find a reasonably priced working motor. We'll be here to help in anyway we can.

 

[boatlex]

Thanks for the support. The cost estimate sounds about right unless I spring for really nice seats. And I guess the hours don't count if I'm enjoying myself

Made some progress - separated the deck from the hull!


Looks like 2 pieces of 0.6" ply, with no bonding between them. Probably originally 0.5 but swollen from water.

I have a ton of nice 1/2" douglas fir ply (purchased for the previous project I started), which I'd like to use. Can you guys help me come up with a layup schedule?

I plan to use epoxy. My thought was, since the outer skin is thick, I shouldn't need extra cloth on that side? So I was going to paint skin and ply with epoxy, then trowel on some PB epoxy, then clamp/screw them together. Then fillet, and do one layer of (cloth? woven? biax?), followed by the other sheet of ply. Fillet again. Finally, several layers to create the inner skin, and heavy tabbing around the sides. But I don't know which type of weave, and which weight to use for each layer (and for the tabbing). Most of what I've read pertains to using polyester, which requires chop mat, but as I understand it that's not recommended for epoxy.

I know I need to pick a schedule to match the original thickness of the transom (skins included). Unfortunately, it's pouring out now, so I can't go measure it until tomorrow

 

[boatlex]

Ugh, I guess a couple posts got deleted during the forum upgrade. To recap:

Chopped out console and livewell. Very happy with the space that freed up. But I noticed that the gunwales were sagging without the extra support. You can see the sagging clearly against the 1x2 layed across the deck:


So I screwed the deck back to the hull, and jammed a piece of wood under the sagging splash well:


With everything properly aligned, I cut several 1x2's to brace the sides of the hull, and screwed them in. They are immediately under the gunwales, to make it easier to align when I put the deck back on:


Deck is removed



Transom is out. I took some measurements... original wood was 1.3" thick, inner skin was 1/8" thick, with an additional 1/8" of tabbing at the edges. I was thinking of using a sheet of 1/2" and a sheet of 3/4". Mud puppy (I think?) pointed out that 2 sheets of 5/8" is exactly the thickness of 1/2 + 3/4. I still need some advice on layup schedule. Planning on epoxy and biax for the transom... 1200 or 1700? How many layers would make 1/8"? What weight cloth to use for stringers & floor?

 

[boatlex]

It runs! Had to run it with the lower unit off and a garden host clamped to the water intake. I only ran it for a few seconds due to noise level (kids were asleep). Needs a few minor adjustments, but it's looking promising! Hopefully I can find a good price on a lower unit at the boat salvage yard, it's a few hrs away though :/

Latest picture: all flooring and all foam has been removed. The only wood left is the stringers, and the plywood strip around the deck/hull joint (does that have a name?)


I'm about half way done prepping the hull for the new transom. I always thought an abrasive cutoff wheel was the tool of choice for this, but a flap wheel works WAY better! Cuts faster, gives more control, and lets you see the layers much more clearly as you breach them.

 

[Woodonglass]

You don't have to use epoxy. In fact I'd recommend using Poly resin. That's what the boat is made out of. Transom wood can be glued up using Titebond III wood glue. It's 100% water proof once cured. Use Deck screws to scew the layers together and then pull em out after it cures. Fill all voids and screw holes in the wood with Thickened resin and then apply a coat of resin both surfaces of the wood paying close attention to the edges. then apply a layer of 1.5 oz CSM to Both surfaces wrapping the edges. Cut the layers about 2" oversized and then Tug, Pull and tear the edges of the mat to make it easier to lay it over the edges. Read the info in the link about Decks, Stringers and Transoms in my signature below.

 

[boatlex]

Thanks for the link. I like that you described the layup changes for both poly and epoxy. I've worked with both (for smaller projects) and never really got great results with poly, so I think I'll stick with epoxy. I find it much easier and more pleasant to work with, aside from the strength benefits. So you think 2 layers of 1700 is enough for the transom and stringers? And a single layer of 7oz top and bottom should do for the flooring?

 

[Woodonglass]

Yup, epoxy is very strong along with the biax fabric. It'll be a Tank when all done!!!

 

[boatlex]

Just placed my order for fiberglass and epoxy. There's no turning back now, I've got money in this thing!

 

[boatlex]

Got all my epoxy and fiberglass and assorted fillers! Hopefully this weekend I'll have time to go get plywood. While I was waiting I started stripping the paint off the boat. Sure, it looks pretty terrible now, but it's actually in decent shape, mostly just needs sanding and fairing. The undersides of those lapstrakes are a pain though.

 

[Woodonglass]

If possible, I'd Highly recommend building a stand about 2' off the ground and flipping the hull onto it. It would make working on it Sooooo much easier. Especially when it comes time for sanding, fairing, and painting.

 

[boatlex]

I do plan on flipping it for the finish work, after I glass in the transom and floors and reattach the cap. Right now I think it's too flimsy to flip. Although, it's super light without any wood in it, so it's tempting to do it now.

 

[Woodonglass]

I disagree. Been there done that. Get some tie down straps and wrap em around the hull. Strap her down and get a friend to help you roll her up and over. Eazy Smeazy. Once she's all "Purdied UP" with paint you can put blankets and pads down and roll her back over and lift her back up. Lots easier when she's LIGHT and less chance of damaging your Nice work. With the 2x4's screwed in place to hold her shape you'll be fine.

 

[boatlex]

That does sound like a good idea. I might end up doing that, but that means I gotta hurry up and decide on colors and paint :/ I didn't use 2x4's as braces, just 1x2's... maybe I should reinforce those a bit before flipping? Or maybe I should reattach the cap? I'm just worried about the hull cracking with all its weight on an 1/8" fiberglass side.

 

[Woodonglass]

With the bracing and straps it'll be fine. Been There, Done That!!! That Boat is MUCH tougher that what you might surmise!!!!

 

[boatlex]

Well, I chickened out and added more bracing anyways:


The 1x2's were doing nothing for strength, they were only added to keep the gunwale spacing constant. Probably would have been fine without the massive overkill bracing, but it gave me the confidence to flip it:


I was pleasantly surprised - it went much easier than expected. And no nasty surprises lurking underneath either.