Wood strip building question
 

I understand the need to plane and sand the outer side of the hull of
wood strip built boats so that it is fair and smooth. You'd
definately want it as smooth as possible to facilitate passage through
the water.

But doing the same to the interior makes me wonder. Fairing the
interior reduces the thickness of the wood strips. Maybe this isn't a
big deal, and it also has the benefit of reducing weight. But I just
wondered.

If you aren't going to show the boat, wouldn't it make sense to just
clean it up and apply the fiberglass?

Thanks, Corky Scott

Wood strip building question
 

If it is not fair, it will be uneven, bumpy

which among other things, means that your glass will not lie flat, but
rather be uneven/bumpy with the potential air pockets, and although I
have no scientific language to back me up, my *experience* over 25 years
of playing with glass and different resins is that bubbles and air
pockets are eventually trouble.

They are weak spots to drop an anchor, crack, and create a pocket for
water/rot, or step on and crack.

Plus, one has put so much effort into the construction by the time you
get to what you are talking about, why stop short and create an ugly
mess that will forever require explanation? I would think that any
potential *extra* strength you might save by not fairing will be loudly
offset by the loss of pride in a finely finished object.

I don't know, the suggestion just give me chills.

My opinion only, worth exactly what you paid for it :)

Jonathan


wrote:
I understand the need to plane and sand the outer side of the hull of
wood strip built boats so that it is fair and smooth. You'd
definately want it as smooth as possible to facilitate passage through
the water.

But doing the same to the interior makes me wonder. Fairing the
interior reduces the thickness of the wood strips. Maybe this isn't a
big deal, and it also has the benefit of reducing weight. But I just
wondered.

If you aren't going to show the boat, wouldn't it make sense to just
clean it up and apply the fiberglass?

Thanks, Corky Scott


--
I am building my daughter an Argie 10 sailing dinghy, check it out:
http://home.comcast.net/~jonsailr

Wood strip building question
 

This may sound like heresy to some but I used a belt sander to rough fair
outside and for all the inside. I knocked off the edges on the outside and
then faired to the second stage with a ROS. Final stage was power
longboard. Inside I sprayed with Dykum blue machinist ink diluted with
alcohol. Then put some rubber under the wear plate on the belt sander to
give it some curve and sanded on the diagonal until there was only a thin
stripe of blue along the seams. Inside was not completely fair but it was
good enough for the glass to lay tight.

Started out with 1 1/8" thick by 1 3/4" wide strips and ended up with a
pretty even 1" thick.

--
Glenn Ashmore

I'm building a 45' cutter in strip/composite. Watch my progress (or lack
there of) at: http://www.rutuonline.com
Shameless Commercial Division: http://www.spade-anchor-us.com

wrote in message
...
I understand the need to plane and sand the outer side of the hull of
wood strip built boats so that it is fair and smooth. You'd
definately want it as smooth as possible to facilitate passage through
the water.

But doing the same to the interior makes me wonder. Fairing the
interior reduces the thickness of the wood strips. Maybe this isn't a
big deal, and it also has the benefit of reducing weight. But I just
wondered.

If you aren't going to show the boat, wouldn't it make sense to just
clean it up and apply the fiberglass?

Thanks, Corky Scott

Wood strip building question
 

For light boats which will be finished bright on the inside, you need to do
a reasonably good job. After all, when using the boat, you'll be looking
at the inside. For canoes and dinghies, i start with a 3" paint scraper
that's been ground to a curve that's tighter than the hull's tightest curve.
Actually, i have several. If the planking is lying fair, this step only
needs to remove the glue dribbles and the feather edges of the strips'
coves. This is followed with a a random orbit sander (P-C 7335) with a soft
pad and a 40-grit disc. Then another pass with 80-grit on the same sander,
then #120 on a foam block and i'm ready for glass. Be careful with the #40.
I've seen folk sand through their canoe.

If the interior isn't to be bright, i'd use the scrapers, the #40, then
epoxy-microsphere fairing putty in major divots and the #40 again. Then
glass.

In either case, even if aesthetics aren't an issue, you want the surface of
the strips to be flat enough that the glass lies flat without ridges or
furrows. Currugated glass would be heavier and weaker.


wrote in message
...
I understand the need to plane and sand the outer side of the hull of
wood strip built boats so that it is fair and smooth. You'd
definately want it as smooth as possible to facilitate passage through
the water.

But doing the same to the interior makes me wonder. Fairing the
interior reduces the thickness of the wood strips. Maybe this isn't a
big deal, and it also has the benefit of reducing weight. But I just
wondered.

If you aren't going to show the boat, wouldn't it make sense to just
clean it up and apply the fiberglass?

Thanks, Corky Scott

Wood strip building question
 

On Tue, 15 Nov 2005 15:59:46 -0500, "Jonathan W."
wrote:

If it is not fair, it will be uneven, bumpy

which among other things, means that your glass will not lie flat, but
rather be uneven/bumpy with the potential air pockets, and although I
have no scientific language to back me up, my *experience* over 25 years
of playing with glass and different resins is that bubbles and air
pockets are eventually trouble.

They are weak spots to drop an anchor, crack, and create a pocket for
water/rot, or step on and crack.

Plus, one has put so much effort into the construction by the time you
get to what you are talking about, why stop short and create an ugly
mess that will forever require explanation? I would think that any
potential *extra* strength you might save by not fairing will be loudly
offset by the loss of pride in a finely finished object.

I don't know, the suggestion just give me chills.

My opinion only, worth exactly what you paid for it :)

Thanks for taking the trouble to respond. Once again, I have left off
crucial details. The boat in question is a cedar strip canoe. The
strips of cedar are normally ripped 1/4" thick and 3/4" in width,
making them as long as necessary.

The edges are then milled using a routing table so that one side has a
bead edge, the other has a cove edge. This means that when the boards
are glued together as the hull is formed around the sixteen stations,
it is already pretty smooth, with no ridges or bumps. It's analagous
to tongue and groove boards.

Since the cedar strips are already pretty thin, and I've heard of
people actually sanding through in spots in their zeal to achieve the
perfect curve, I just wondered if anyone had made a canoe this way and
decided not to fair the interior.

Reading through the book by Gill Gilpatrick about how he builds cedar
strip canoes (he teaches kids to build them in shop and also teaches
adults to build them and has written a book about it, and has build
many many canoes.), he is a bit of a minimalist. He doesn't lap join
his strips, he just butt joins them and doesn't even care if they
don't meet at a station. He advocates the minimum sanding necessary
to fair the hull and stop there.

As to the interior, well lets just say he'd rather be paddling than
sanding. In addition he does not advocate using either bow or stern
stems. He just bevels them with a rough hand saw and clamps them
together with glue. He does lay a large bead of resin mixed with flox
or the like into the bow and stern area and he claims that makes as
strong a bow and stern as adding stems does. He is a Maine canoe
guide and takes folks down some very rocky rivers and claims he's
never seen one fail, even though the rest of the canoe might be
trashed.

Anyway, no need to worry about dropping an anchor onto the hull: it
won't be carrying an anchor.

No need to worry about looks either, it should have the look of a
carefully assembled wooden hull with no ridge, gaps or bumps, if I do
a decent job of milling the strips and adding the bead and cove edges.
One more point, once I mill the strips, I will be running them through
a planer to get them to the exact 1/4" thickness so they will be very
smooth before they are assembled. No saw marks to remove through
sanding.

Thanks again.

Corky Scott

Wood strip building question
 

On Wed, 16 Nov 2005 12:31:16 -0500,
wrote:

As to the interior, well lets just say he'd rather be paddling than
sanding. In addition he does not advocate using either bow or stern
stems. He just bevels them with a rough hand saw and clamps them
together with glue. He does lay a large bead of resin mixed with flox
or the like into the bow and stern area and he claims that makes as
strong a bow and stern as adding stems does. He is a Maine canoe
guide and takes folks down some very rocky rivers and claims he's
never seen one fail, even though the rest of the canoe might be
trashed.

After reading this I felt it was difficult to understand what I was
saying.

Cedar strip canoes are built using thin cedar strips that come
together to a narrow profile at the bow and stern. Some kit's and
plans recommend a stem at each end, some do not. The stem can be an
inner stem AND outer stem, or an inner stem only. You can also build
the canoe with no stem at all.

The stem is usually very thin laminated strips that form the curve of
the bow and stern. They are layed up around the stem forms and then
beveled so that the outer end is more narrow than the inner end. This
is all so that the strips can bond flat against them as they narrow to
the bow and stern.

But you can also bevel the strips themselves and simply glue them to
each opposite side's strip around the stem form. The stem form is
usually bevelled too, to allow the strips to come together where
they're supposed to.

Done the latter way, there is no reinforcement for the bow or stern.
That's what the large bead of thickened resin, squeezed against the
inside of the bow and stern does, it becomes the stem, so to speak.

Corky Scott