Re: The Dumb-Ox -- replies and a question or two
--- In bolger@y..., "rnlocnil" <lincolnr@m...> wrote:
for a given weight. That has nothing to do with how the knited
fabric backs up wood fiber. Even glass is not as stiff as wood, and
sheathing will not stop a pooch from forming. We went into this
Xynole thing at length in a thread a few months back, and I sure
learned some stuff, but I wouldn't be using it for the repair.
Sounds like you will get some heavy glass on it from the chine tape.
By the way I know you are "supposed" to use a strongback for this
design, but that doesn't mean people always do, so it is best to
check. Using one is presumably an advantage with this kind of
incident, since you won't loose much symmetry
> I'm very skeptical of that understanding. Fiberglass as a materialis
> VERY strong. I suspect Xynole may be tougher, but not stronger.Isn't
> Xynole supposed to be very flexible as well? In that case the woodmay
> crack before the Xynole gets a significant load on it. Before youuse
> Xynole structurally, I think you should make up some plywood testthat
> pieces with fiberglass and of Xynole, let them set a few days, and
> break them. I know that Parker says it is stronger for it's weight,
> but I really can't believe it. If they really had something like
> it would be marketed right up there with carbon and Kevlar and soon.
> Sounds like it's good for a protective covering over wood, tho.Agreed, "stronger" may just refer to the tensile strength of the yarn
for a given weight. That has nothing to do with how the knited
fabric backs up wood fiber. Even glass is not as stiff as wood, and
sheathing will not stop a pooch from forming. We went into this
Xynole thing at length in a thread a few months back, and I sure
learned some stuff, but I wouldn't be using it for the repair.
Sounds like you will get some heavy glass on it from the chine tape.
By the way I know you are "supposed" to use a strongback for this
design, but that doesn't mean people always do, so it is best to
check. Using one is presumably an advantage with this kind of
incident, since you won't loose much symmetry
I'm very skeptical of that understanding. Fiberglass as a material is
VERY strong. I suspect Xynole may be tougher, but not stronger. Isn't
Xynole supposed to be very flexible as well? In that case the wood may
crack before the Xynole gets a significant load on it. Before you use
Xynole structurally, I think you should make up some plywood test
pieces with fiberglass and of Xynole, let them set a few days, and
break them. I know that Parker says it is stronger for it's weight,
but I really can't believe it. If they really had something like that
it would be marketed right up there with carbon and Kevlar and so on.
Sounds like it's good for a protective covering over wood, tho.
VERY strong. I suspect Xynole may be tougher, but not stronger. Isn't
Xynole supposed to be very flexible as well? In that case the wood may
crack before the Xynole gets a significant load on it. Before you use
Xynole structurally, I think you should make up some plywood test
pieces with fiberglass and of Xynole, let them set a few days, and
break them. I know that Parker says it is stronger for it's weight,
but I really can't believe it. If they really had something like that
it would be marketed right up there with carbon and Kevlar and so on.
Sounds like it's good for a protective covering over wood, tho.
--- In bolger@y..., "pseudodion42" <pseudodion3@a...> wrote:
snip
> Xynole, as I understand, is as strong or stronger than fiberglass.
> There is some discussion about this at the Woodenboat forum, but my
> main source of information was R. Parker's "The Sharpie Book."
snip
Dip in the side? A tiny little "wow"!
I won't confess that I put frame two in frame three's place and vica
versa on my Diablo. And therefore I can't tell you how glad I was
that I noticed it before I epoxied either in place.
In any case, a gallon or two of epoxy thixkened to a peanut butter
consistency with micro balloons will fair an awful lot of "dip", sand
quite easily, only ruin a couple of shirts and help the Gougeon
Brothers top up their 401K all at the same time.
Bruce Hector, wondering if any epoxy manufactures have shares listed
on the NYSE or any other exchange. Perhaps with an aging boomer
population, having time on their hands and always wanting to build a
boat or two it would be a good investment. Or maybe I could just take
my dividends in epoxy.
I won't confess that I put frame two in frame three's place and vica
versa on my Diablo. And therefore I can't tell you how glad I was
that I noticed it before I epoxied either in place.
In any case, a gallon or two of epoxy thixkened to a peanut butter
consistency with micro balloons will fair an awful lot of "dip", sand
quite easily, only ruin a couple of shirts and help the Gougeon
Brothers top up their 401K all at the same time.
Bruce Hector, wondering if any epoxy manufactures have shares listed
on the NYSE or any other exchange. Perhaps with an aging boomer
population, having time on their hands and always wanting to build a
boat or two it would be a good investment. Or maybe I could just take
my dividends in epoxy.
Thanks to all for your answers and suggestions regarding the stress
failure in the ply. To answer some questions:
Xynole, as I understand, is as strong or stronger than fiberglass.
There is some discussion about this at the Woodenboat forum, but my
main source of information was R. Parker's "The Sharpie Book."
Secondly, the Dobler is not instant boat style construction. Its
frames are set up on a strongback, two longitudinals run fore and aft
on each side of the boat, and then the planking is hung and screwed
and glued to the longitudinals. The bow panels are stitched and glued
together, as well as the seams aft of station one.
The boat has come out surprisingly fair although there are two
trouble spots that I'm not sure that I can do anything about now that
the panels are glued in place. There is a slight hump at the knuckle
of the lower bow panel at station two -- about midway between the
waterline and the sheer. This is on the port side. On the starboard
side there is a dip between station 1 and station two at the sheer.
How I missed these while fairing is beyond me. Is there a possibility
of a fix? Or must I consider these glitches "design elements?" :}
Thanks,
Dennis
failure in the ply. To answer some questions:
Xynole, as I understand, is as strong or stronger than fiberglass.
There is some discussion about this at the Woodenboat forum, but my
main source of information was R. Parker's "The Sharpie Book."
Secondly, the Dobler is not instant boat style construction. Its
frames are set up on a strongback, two longitudinals run fore and aft
on each side of the boat, and then the planking is hung and screwed
and glued to the longitudinals. The bow panels are stitched and glued
together, as well as the seams aft of station one.
The boat has come out surprisingly fair although there are two
trouble spots that I'm not sure that I can do anything about now that
the panels are glued in place. There is a slight hump at the knuckle
of the lower bow panel at station two -- about midway between the
waterline and the sheer. This is on the port side. On the starboard
side there is a dip between station 1 and station two at the sheer.
How I missed these while fairing is beyond me. Is there a possibility
of a fix? Or must I consider these glitches "design elements?" :}
Thanks,
Dennis