Core Sound 15 -- The Decision and Some General Questions

[Charlie Jones]

Cabosil. After mixing the wood flour, add about 10% cabosil. When you purchase wood flour ( what ever they call it) from the Gougeon's, it already has 10% cabosil in it. Sometimes you need a tad more.But wood flour alone usually will sag unless it's REALLY thick, and then it doesn't make a good, smooth fillet.

What I do is run all the fillets, say- inside both chines, then go back and roll out the tape as soon as I'm done filleting. Carefully lay it in - I roll the tape and then unroll it onto the fillet. Then I use a fairly dry brush to put it into place, adding epoxy as needed to wet it out.If I get "waves" I brush back the other way til they go away. If you brush lightly you'll usually not disturb the fillet though. Normally a matter of just being gentle.

[Tom Lathrop]

On filets that will be taped over, you can help prevent sagging by adding wood flour, sawdust or cotton fibers to the mix.  These will greatly reduce or eliminate sagging.  Wait until the filet is a bit stiff to lay the glass on unless you are gaining more skill at this.  I like to pre-wet the glass tape on a long piece of plywood with plastic sheeting taped over it.  squeege the epoxy into the tape for a more evenly saturated job,  Paint on a thin coat of epoxy in the joint area and lay on the tape.  If you have done this correctly, there will only be a couple areas that need more epoxy and there will be no runs.  Add any extra layers of glass at this time also. 

On large joints requiring heavy cloth or biaxial glass, peelply and a serrated roller make for a superior job that requires less sanding or clean up later.

[Oyster]

[sneaking in here quietly with all the pros but leaving the door slightly ajar] When wetting tape for seams I  use a high dollar tool, a split three inch pvc pipe about three feet and have the piece glued to a long board with thickened epoxy along the underside edge. This gives me a half moon cup which to contain my resin which confines it from running everywhere and even soaking valuable materials into wood flat surfaces or running off cured and old wooden surfaces being reused.[tiptoeing quietly in reverse and into the darkness of the evening]

[Charlie Jones]

Now THAT'S a decent idea- why didn't you tell me that 20 years ago??? ;D ;D ;D

[Oyster]

Now THAT'S a decent idea- why didn't you tell me that 20 years ago??? ;D ;D ;D

Well you know what they say dontchu, If I had told you, I would have had to.............................to  run your fillets and tape too. ;D

What was that gong I just heard?? HEHE!

[Dale Niemann]

When I was working on "Lively" I used a belt sander belt cut open then stretched over a quarter inch ply board.  I wrapped the ends over and stapled them on the top.  Glued on a couple of broom handles on top and it worked great.

Dale

[Guest Dennis M]

Progress, but no pics!

The foredeck has been cut and dry fitted. I am wondering how folks have attached this. Screws along the centerline and inwale? Will that be sufficient, do I also need some on the stringers?

I have cut and fitted the c/b cap. One side of the c/b case is higher than the other and is not level on top so the cap twists downward to one side. Would taking a plane to the high side and shaving it down be the best way of rectifying the problem? I am not so sure that sanding will do the trick as that is probably what made the top uneven to begin with.

Finally, I am ready to dry fit the gun'ls. How far apart should I place screws? Since this will be "sacrificial" I imagine that screws every 8 inches should be OK, but would like to hear what others have done.

Primer and paint go on the inside this week, or so I hope.

Dennis

[John Burritt]

The c/b cap should be flush w/ the center thwart.  Adjust whichever side of the trunk is necessary to make that happen - plane the high side, or build up the low side.

Screws down the centerline of the foredeck are fine, as long as they're close enough together that you don't leave humps in between.  Same along the inwales.  Can also use ring-shank copper nails.  If the foredeck is to be finished bright, figure on putting on a toe rail to cover the fasteners.  W/ a painted deck, you could recess the fasteners and fair over them.  Toe rail still isn't a bad idea.  A trim strip will cover the centerline.

I'd think the screw spacing you suggest should work.  Might think about shortening it to 6", particularly at the forward part where the bend is most severe.  I'd get the foredeck and side decks on and ready to be finished before messing w/ the gunwales.  They'll tell you where exactly the gunwales should be placed.

[Guest Dennis M]

John, thanks for the tips.

Keeping humps out of the foredeck will mean putting a screw every half inch .

Is there any advantage to bedding the deck in dolfinite or some such thing so that the foredeck can be removed? My previous boats foredeck was glued and screwed and has given no trouble, but when I made some modifications to it a few years ago, it would have been nice to have simply removed the thing without then having to repair the damage wrought by removing the old one.

[Greg Luckett]

.....Keeping humps out of the foredeck will mean putting a screw every half inch ....

You are not trying to bend the plywood deck in more than one direction, or are you? Plywood does not bend in more than one direction at a time very easily.

[John Burritt]

I see no reason to use anything other than thickened epoxy.  Once the foredeck is on, you want it to stay that way.

The screws need to be close enough together that the plywood's natural tendency to flatten out doesn't lift it off the inwale or center king plank in between.  One way to avoid that would be to make cauls (clamping blocks) out of scrap to spread the load along the edge.  I'd make them long enough that they'd almost meet, but short enough that they're not bridging away from the inwale.  Check that shape of the bottom edge conforms to the deck shape - should be almost flat along this length.  Put duct tape on the bottom.  Drill an oversized hole thru it and screw it down w/ a drywall screw thru a fender washer (to spread the load).  Doing this, you'd only have small holes to fill rather than hiding screw heads.

[Guest Dennis M]

What kind of tools do I need to work with the aluminum mast -- attach fittings and etc?

Also, how does one get the aluminum permanently joined? Will wrapping the end of the 2.25" piece in tape and epoxy until it fits snugly in the 2.5" piece work?

Thanks

[Greg Luckett]

I use a drill motor with the appropriate bit, deburring tool, taps of the appropriate size, aluminum pop rivits of the appropriate size and pop rivit tool, and a good hacksaw if needed. I do not like using SS pop rivits on aluminum as they tend to have corrosion problems but I do use SS machine screws.  I suppose the SS rivits would work as well but somewhere over the years I was taught to avoid SS and Aluminum, not remembering from whom or when.

[Guest Dennis M]

No pics. . . but progress.

The inside of the boat is painted; bailer installed, rubrail mostly painted and ready to be attached. The only thing left -- put on the fittings, prepare the masts, and get the rudder, tiller and hiking stick done. I ran out of both primer and paint so the thwarts are naked as jaybirds. I haven't figured out what to do with them. They are clear pine and I have been waffling back and forth about whether they should be a hardwood of some sorts. I will not varnish them, whatever the case.

[Greg Luckett]

Man! I feel your pain. I spend most of the time figuring out what is the best solution, then a very short time actually building.

[Guest Dennis M]

Thwarts-- Is there any objection to using a polysulfide adhesive on the thwarts? This would make for easier repairs, or so it seems.

[Guest Dennis M]

Graham, the plans call for "about 4 ft" of shock cord for the c/b downhaul. Is there anything special for me to attend to when I set it up -- am I trying to achieve a certain tension for it to operate properly? Thanks, Dennis

[Guest Dennis M]

High Winds, Thunderstorms and Rain have made it necessary for me to hold off on launching the boat. Tuesday will be the day if all things go well. Winds are forecast to be 10-15 mph, a good day to put the boat through her paces. A friend of mine will bring a digital camera, so I might even have some pics later in the week.

[Designer]

We just tie the shock cord in a loop so that it is doubled.

Good luck with the launching.

[Guest Dennis M]

Thanks, Graham.

There are a couple of things left to do on the boat.

1. I need to fashion the rowlock supports, but do not know how high to make them. Do you have a recommendation here? I might forego the rowlocks altogether, and get a paddle.

2. I need to place mooring cleats of some kind aft. I was looking at pics of Green Heron from the EC and noted you had some sort of eye screwed or bolted through the transom. What are those and are they better than using a horn cleat?

Thanks