Exterior grade Lauan
mjes...@my-dejanews.com
the skin? How well does it hold up?? Thanks, Mike
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Mike Goodwin
like 'Smith's ' or 'Rot doctor's cpes ' and some times a laminating epoxy
for a harder finish.
Mike
mjes...@my-dejanews.com wrote in message
<72ro11$gkb$1...@nnrp1.dejanews.com>...
Dave Carnell
(Wilmington, NC) recently told me over the phone they had some. When I got
there to look at it, no one had ever heard of it. Twenty years ago I was sold
some "exterior lauan". The boat I built was stored outside upside down and the
bottom delaminated over the first winter. I don't believe there is honest
exterior lauan.
Dave Carnell <http://home.att.net/~DaveCarnell>
Ydissacm
No, or in any case, I've never seen a label printed on it as one might see on
APA rated ply. I only reply here to report that I have experienced a wide
variety of results using 3/16" (they call it 1/4") building-store luan as
concerns delamination. I have used it, over the years, to construct various
covers, boxes, and other (mostly unpainted) utility-type applications and some
of these have been exposed more-or-less continually to the weather. My
experience is that for years it held up well, but in a few more recent projects
some of this material has delaminated the first time it got wet for a day, or
so. Other pieces have lasted through many dozen wet-dry cycles as one would
expect from exterior ply. I have also noted both characteristics within the
same sheet!! Part of it delaminated almost immediately and was cut off and
discarded. The remaining piece seemed intact and was reused as a temporary
(two years now) cover for a dog food-and-water area with no noticiable
deterioration (gluewise). Go figure.
> Twenty years ago I was
>sold
>some "exterior lauan". The boat I built was stored outside upside down and
>the
>bottom delaminated over the first winter. I don't believe there is honest
>exterior lauan.
I agree, nothing dependable, in any case.
Mike Cassidy ydis...@aol.com
North Carolina, USA
Ron Wilson
mjes...@my-dejanews.com wrote:
> Has anyone had any experience building boats using exterior grade Lauan for
> the skin? How well does it hold up?? Thanks, Mike
>
> -----------== Posted via Deja News, The Discussion Network ==----------
> http://www.dejanews.com/ Search, Read, Discuss, or Start Your Own
You might take a look at the wood sciences column in the most recent
Woodenboat magazine. If I remember correctly, the drift of the info on lauan
was that it is poor both for resistance to marine critters and for dimensional
stability. Delamination would probably be more a question of whether the
adhesive used in making the plywood was water-resistant, but I suppose the poor
dimensional stability could cause rupturing of the adhesive in some situations.
As I understand it, sealing the ply with epoxy is merely postponing the
inevitable. Unless somehow you are able to hermetically seal the material,
prevent osmosis, avoid any damage that breaks the seal and keep an inherently
unstable surface from checking, you will end up keeping moisture in, rather
than out, with the epoxy. Whether this will shorten the life of the boat
unacceptably in real life, I don't know, but I'd love to hear data from actual
experiences. My wild guess would be that on stitch'n'glue boats, that are
essentially fiberglass boats with the form left inside, it doesn't make much
difference in the long run if the form rots. On designs where the ply will
continue to be a structural part of the boat, it might be a more important
issue.
ron wilson
Mike Goodwin
in Chesapeake , Va.( I live about 8miles from the plant) I have talked with
their tech-reps. and it is indeed made with exterior glue and the sheets
that I buy at Home Depot ,are labeled as such ,the stuff at Lowes is
interior grade and so labeled. I know several local lumber yards that carry
both grades aprox. $8 int. or $10 ext. Home Depot sells ext. for $7.80 per
sheet (when they have it )
I have seen the interior grade nailed up on the ceiling under a porch roof ,
no direct exsposure to rain and it peeled down in six months .
Anyway,if you are looking for a retailer in your area call Chesapeake
Hardwood Products 757-543-1601
Mike
Dave Carnell wrote in message <36519520...@worldnet.att.net>...
>Has anyone ever found exterior lauan? Lowe's Contractors' Yard here
>(Wilmington, NC) recently told me over the phone they had some. When I got
>there to look at it, no one had ever heard of it. Twenty years ago I was
sold
>some "exterior lauan". The boat I built was stored outside upside down and
the
>bottom delaminated over the first winter. I don't believe there is honest
>exterior lauan.
>
>Dave Carnell <http://home.att.net/~DaveCarnell>
Marcel Charpentier
old. Both are fiberglassed on the outside of the hull and sealed throughout in
epoxy. Both boats have held up extremely well. I'm now building a Cape Charlie
for my son with this material. I've also had a piece of lauan lying on the
ground for three years under snow, fallen leaves and constant wet conditions.
It has held up as well as I would expect any exterior grade plywood. It's
cheap, splinters easily, not as good looking or pleasant to work with. You need
to pick through the pile carefully to get the best pieces. If you can afford
it, use okoume but you can build a serviceable boat with lauan in my opinion.
gabriel
recently tested a piece of luan that i wanted to use
and found it unsuitable. I boiled it for about ten minutes and it delaminated.
Other samples from other lots did not delaminate when
boiled. I dont know of a rating system for this material. The junk I am seeing from
the big retailers is from indonesia and it is really
very poor as far as the glue is concerned.
Ron Wilson wrote:
> mjes...@my-dejanews.com wrote:
>
> > Has anyone had any experience building boats using exterior grade Lauan for
> > the skin? How well does it hold up?? Thanks, Mike
> >
> > -----------== Posted via Deja News, The Discussion Network ==----------
> > http://www.dejanews.com/ Search, Read, Discuss, or Start Your Own
>
Migchelsen
fiberglass tape on the seams. Prepared that way and with a good paintwood,
costwise it beats marine plywood.You can build a good 12.5 ft skiff for under
$300. I will never go back to marine plywood.
Migchelsen
The glue is marine quality. If they don't know what it is in your
neighbourhood, go to a flooring company. It is used under other names as
subflooring under wall to wall carpets. In Quebec it is called Philippine
Mahogany. In the Canadian Maritimes they call it Meranti. and sold in BB grade,
perfect for small boats and canoes.
Classic Boatworks of Maine
Luan, one is meranti, and the other 2 names do not come to mind at this
early hour. But there is NO mahogany in the Philipines! :^)
--
Good Luck and Fair Seas
Marshall and Jo Duhaime,Jr.
Classic Boatworks of Maine - We build and restore classic wood boats.
http://www.nemaine.com/classicboatworks
Migchelsen <migch...@aol.com> wrote in article
<19981117225902...@ng37.aol.com>...
Migchelsen
usually slighty reddish. People who don't know all the specifics called it
Philippine Mahogany. And the name stuck.
Migchelsen
anybody who has boiled his boat to find out how good it was?
Glenn Ashmore
> Why is boiling of plywood considered a fair test for its quality? Is there
> anybody who has boiled his boat to find out how good it was?
Boiling is the standard test for marine glues used by most standards
organizations. A fundimental principle of engeneering is the margin of
safety. There are so many unknowns in designing for actual use of any product
that almost everything where human lives might be at risk is designed with a
large safety margin. Notable exceptions to this rule are special purpose
single use products where safety is sacreficed for performance as in some
Whitbread boats.
I think the boil test must have been concieved by the screw and nail industry
shortly after the introduction of marine adheasives. Oddly enough, only a few
epoxy formulations can pass the boil test.
All that said, I have not found any luan plywood in the last 5 years that I
would consider using in a boat that might be subject to any stress or that
would remain in the water for any lenght of time. Of course, I could say the
same thing about a lot of the "marine" plywood sold in many retail outlets
these days.
--
Glenn Ashmore
I'm building a 45' cutter in strip/composite. Watch my progress (or lack there
of) at: http://www.mindspring.com/~gashmore
DSmith3426
using marine ply vs other types of wood. In my opinion afer spending countless
hours removing and replacing the floor in my 19ft ski boat I chose to use
marine ply. The cost of the material is nil compared to the hours i have
invested in the project. $80./sheet of 4x8x3/4 so what. Unless you are in
a high production environment where every penny counts why not use the best
materials available?
alma
mjes...@my-dejanews.com wrote:
> Has anyone had any experience building boats using exterior grade Lauan for
> the skin? How well does it hold up?? Thanks, Mike
>
> -----------== Posted via Deja News, The Discussion Network ==----------
> http://www.dejanews.com/ Search, Read, Discuss, or Start Your Own
Exterior grade plywoods are susposed to use the same glues as marine grade.
However they are inferior because of the quanity of laminations thereby greatly
reducing it's strength.
As a boat builder I would not recommend it on any craft of speed or size.
ART
Chas
have a lot of small (half inch or less) voids in the inner plys. It is only
3 ply with a thick center ply. What is the standard for marine ply, does it
only cover the glue or does it regulate the minimum number of plys and
plugging?
Thanks
Charles
Freezing my butt off in Alaska, but dreaming of sailing.
Migchelsen
small boat that only goes in the water on a very nice sunday afternoon. You
don't use a 10 pounds hammer on a penny nail either. See my other message about
Lauan PLUS epoxy. I once built a 16 ft. Dutch scow with leeboards. Used quality
marine ply for the side panels, exterior ply for the bottom. Covered the chine
seams with fiberglass tape and epoxy. After 10 years the tape on the bottom was
OK, the tape on the sides started to come loose. The epoxy had not soaked in as
deep into the quality marine plywood as into the soft, open grain of the bottom
plywood. It is the combination of ply plus epoxy that does it. And only for
small boats for leisure.
alma
have a stronger material. But would you save in expense? I've built wooden boats
for a long time and there is no real substitute for good marine plywood. Using
exterior for decks,bulkheads,and other non-important items will work but make sure
you seal all edges and surfaces not covered but glass. As for framing, plywood does
not hold fastenings as well as oak,pine,and such woods it's the nature of the beast.
ARTHUR W. STAPLES
Frank Ellinghaus wrote:
> On Thu, 19 Nov 1998 22:35:52 -0500, alma <mem...@injersey.com> wrote:
>
> >Exterior grade plywoods are susposed to use the same glues as marine grade.
> >However they are inferior because of the quanity of laminations thereby greatly
> >reducing it's strength.
>
> If you use 1/4-inch exterior lauan and laminate this together with
> epoxy (for frames, seat-tops, bulkhead) - wouldn´t this give similar
> strength than marine grade plywood?
>
> Frank