Need Help With Stortriss Sailboat-Keel bolt,rudder and wet foam question

[Stortriss]

Just wondering if anyone knows of this sailboat. I an a complete newcomer to sailing and had this boat almost given to me. Its a Stortriss 5.25 meter fiberglass sailboat(quit making them in 1972 think) and i just want to clean it up and throw it in the lake here in sweden before the summers gone.The boat has been setting in the weather on land for some years,not used.
My questions are- THE KEEL :?:- 1-wonder how important it is to check the keel bolts, the seal(of some kind of hard filler like fiberglass,is cracked in places and loose. Thinking of just cleaning it up and painting it. Its pretty rusted.
2-Also wonder if i should try to drop it down a bit and look at the bolts.(its hanging on wooden stands on a trailer.
3-Would really like to know if the filler around the keel is structural support, thinking of just sealing it up with a type of silicone adhesive they use here for boats and taking it apart next year when there is more time.
WET FOAM BETWEEN DECK AND HULL:?:-- Seems some water(probably a lot got inside and soaked the foam. Even has opened the fiberglass in the back (theres a space for keeping things at the back so its no damage to the hull),
Been letting it drain and air, seems to be stopping, but it must be wet up inside and i wonder about mold..? Wonder if anyone has experienced this, and what can be done about or if its ok to as is (at least for this season-summer is VERY short here..
RUDDER:?:-Anyway to find out the size and shape of the rudder ,i must make one.
Blueprints would be nice to find out about the keel support and the rudder.
Thanks for any advice!!!Just hope to get in the water and play around this summer with the family!!!

 

[PAR]

Welcome to the forum.

Is this your boat? They built about a thousand of these across the 1970's. The ballast is only 180 kg, but checking to see if it's solidly mounted is a good idea. This is because it's a big hunk of iron, not lead and the problem with these is once the joint leaks, the iron rusts and swells up, eventually bursting open seams, joints, etc.

There's not a lot of value in this boat, though others by this designer are praised (like the Vega). The seam sealant isn't likely structural so much as just a seam sealant, so reef out what's in there, and apply new, then go have some fun on the local puddle. You can make serious repairs this winter if desired.

 

[Stortriss]

Thanks Par!!
Yep thats the boat....was looking at the joint today , mostly loose around the front and rear ends where theres a big gap of about an inch. Was happy to see some black silicone stuff sticking out from under the hull between the keel. At least there is some chance the bolts/keel isn't completely rusted out inside.Took out fiberglass filler here and there and cleaned it up a bit. Gonna use some sikaflex sealant they gave me at the boat store and think about MAYBE dropping the keel over the winter and checking it out...I hope to be in the local puddle in a couple a weeks!
Any tips on rudder design ? Have a good idea but have no clue of the dimensions....any rule of thumb i can use for width ,length,thickness, if i can't find the right dimensions....
Have some 20mm plywood was thinking of using that and painting it.....maybe i can find one to measure...
Happy sailing!!!

 

[PAR]

Plywood makes lousy appendages, but if you want a temporary one, it'll be fine. A strip planked rudder blade is easy to do and much stronger and more durable than plywood. West System's site has a good primer for this build method, so have a look over there.

Also this thread:

http://www.boatdesign.net/forums/fi...building/dimensions-kick-up-rudder-49139.html

 

[Stortriss]

Thanks Par! I just need a temporary fix for now, (I`ve heard here in Sweden that summer is "the warmest day of year"....comes and goes fast,so i think speed of getting it into the water is priority). I have some 20mm plywood, was thinking of trying it,not sure if would need fiberglassing,maybe just paint it... since we are newbies don't think we´ll be getting crazy with it....or going far. Just want go out and cruise around. If all goes well this summer then we can think of doing everything right for next season....I´ll check the West Systems site......

 

[PAR]

If you must use plywood, multiple layers is better than one thick piece. For example, 3 layers of 1/4" (6 mm) will be much better then one of 20 mm. I just made a centerboard of 4 layers of marine meranti. 20 layers of wood veneer (total across 4 pieces), plus 3 epoxy glue lines. To further stiffen this board, I canted the inner layers at 22 degrees to each other, to improve cross grain stiffness and help stave off "rolling shear" between the veneers, which is the most common failure point with plywood appendages.

For a temporary board you 20 mm will get you by for a while, at least time enough to to consider other options.

 

[SukiSolo]

I'd second PAR's advice, but add that if you 'cap' the edges of the board with solid timber it will help seal and protect the vulnerable edges. Use a moderately dense fine grain timber like Khaya, Sapele even sycamore/maple. This will also act as a protective capping for when you hit something, or scrape it. A large lump of epoxy with suitable fillers will substitute reasonably and should definitely be used at the bottom and tip of the leading edge.

Note, if you use sycamore and the protective coating is breached it WILL turn black especially in sea water.

Strip plank is definitely better + glass sheathed, as a long term solution.

 

[PAR]

On plywood and solid wood (striped or other wise) I use rope (single braid polyester usually) set in a groove with epoxy, around the leading and bottom edges, if not all around. This is very tough and will save the edges of the board from strikes and moisture ingress. On bigger boards, I've sometimes used a thickened mixture of pulverized stone (decomposed granite typically), again set into a groove with epoxy. I use the stone as the bulking agent in the epoxy mix. This is especially hard and offers great protection, but is harder to form without some practice (I often make a mold for the edge and cast the stone thickened goo edge).

Both of these tricks don't require a fabric sheathing, but it's a good idea anyway, if only for additional abrasion resistance. I recently made a ballasted board and cast the leading and bottom edges with lead. This will serve the same protective role and is easy to repair if struck, plus places the ballast aspect of the board at the lowest point in the boat, when it's retracted. This particular board carried about 60 pounds of lead, most along the leading and bottom edges, with some depth behind it to make up the weight. The board was pre-sheathed with two layers of 6 ounce cloth, but the lead was left natural (painted) and set into a centerline groove with epoxy and a few stainless pins holding it in place. Bullet proof, easy to repair and an ideal weight placement.

There's lots of ways to skin this kitty, so while you're enjoying your temporary board, you can dream up it's eventual replacement. Lastly don't skim on the epoxy. 3 coats as a minimum all over every thing. These things by their nature take a beating, so you want any breaches to be heavily protected. A substantial film thickness is the ticket, especially if coupled with fabric.

 

[Stortriss]

wow! Thanks for the great advice SukiSolo and Par! Sounds like theres lots of years of knowledge on this site...Sounds like a project for the long winter here........Sure i can fix something up for now......
Just one more question....
Not sure if i can find the pins that hold the rudder to the boat so I´m hashing around ideas in my head and wonder what yous think about using one long piece of threaded rod(its about 10mm DIA) to somehow attach the rudder to the boat. Should be strong enough and i can keep an eye on it while I´m looking for the right parts ...
Thanks again!!!!

 

[SukiSolo]

Use 10mm solid rod, not threaded. The threaded will chew up the gudgeons pretty quickly and you need a tightish smooth fit. Personally I don't like long through pins, had one come off and bend in the Round the Island race 2010 at 10-12 Kn and bent itself. When you try and remove a bent long pin through the top fitting, expect to curse. Naturally they are almost impossible to straighten whilst sailing....or even afterwards! We did jury rig a large clevis, to get ourselves home.

At that size boat, 10 is a minimum, maybe 12mm might be better. On dinghies I prefer the Seasure brand type fittings. Your boat is bigger and will require something a bit more substantial to allow for bad weather. I'm sure you can googly something suitable for your craft. Maybe I'm just old fashioned but a well mounted 'traditional' pintle and gudgeon set up with lock down still takes some beating.

 

[Stortriss]

Thanks SukiSolo! I think 12mm is for sure better, was just guessing at the size from looking at the size of the holes on the mounts on the boat. Will have to measure them to be sure. I`ll figure something out, was just thinking threaded rod would be easy to mount but I´m sure your right about it chewing up the mounts.....was just an idea....Thanks....

 

[PAR]

Pintles and gudgeons are easily available though online or mail order services. A continuous rod pintle is possible though I don't like them much. This said a fabrication shop can also easily make up a stout set too, for not a lot of money.