Re: MDO Questions
--- Pierre wrote:
overlay', there is also a 'high
density overlay', HDO. In my
experience it is used commercially
for concrete formwork, to give the
cast concrete a smooth finish, and
for durabilty for reusing formwork.
Also, I hear it is used by sign
makers for durablilty in exterior
signs.
The local lumber yard that caters
to the Building Contractors stocks
the stuff in my town.
You want the 'paint grade' because
they also sell the 'concrete formwork'
grade which I think is coated with
some chemical to assist the concrete
from not sticking, and probably would
mess up the adhesion of the epoxy.
> I thought MDO was the generic termMDO stands for 'medium denisty
overlay', there is also a 'high
density overlay', HDO. In my
experience it is used commercially
for concrete formwork, to give the
cast concrete a smooth finish, and
for durabilty for reusing formwork.
Also, I hear it is used by sign
makers for durablilty in exterior
signs.
The local lumber yard that caters
to the Building Contractors stocks
the stuff in my town.
You want the 'paint grade' because
they also sell the 'concrete formwork'
grade which I think is coated with
some chemical to assist the concrete
from not sticking, and probably would
mess up the adhesion of the epoxy.
I have used a lot of MDO. For the topsides of my Dakota I used good two
sides. The results were excellent. Where one side would not be seen, I used
good one side. I always put the best (paper) side out. It has the better
grade in the outer ply. Some of the good one side 1/2" came with paper on
both sides, but the bad side (a few small voids) was marked with the word
"BACK". I sheathed the outer side with epoxy and cloth. The inner side of
the hull got epoxy (probably unnecessary) and paint. There was already epoxy
at the filleted and taped corners, so I just kept spreading over the whole
surface. The cabin interior just got paint.
The paper side of MDO really sucks up the resin. I spread two layers of
epoxy before I rolled out the cloth.
BTW, I am mainly referring to 1/2" which is 5 ply and pretty good quality.
The 3/8" is 4 ply with thick inner plys running 45 degrees to each other and
thin outer plys. It is not nearly as strong. i used 3/8" mainly for
cabinetry and the ceiling and cabin top where I wanted to save weight.
I went to a local lumber yard, not H.D. or one of the chains, and spoke with
the contractors' outside sales rep. They usually are more knowledgeable than
the people at the counter or the loaders in the yard. Lots of residential
and commercial builders use MDO for such things as decorative sheathing of
steel porch columns, etc. He was able to order what I needed from their
regular sources and there was no shipping charge. I ordered at four
different times and got MDO from more than one mill. The best was Canadian.
Unfortunately it was a somewhat more expensive due to that ridiculous tarif.
Vince Chew
sides. The results were excellent. Where one side would not be seen, I used
good one side. I always put the best (paper) side out. It has the better
grade in the outer ply. Some of the good one side 1/2" came with paper on
both sides, but the bad side (a few small voids) was marked with the word
"BACK". I sheathed the outer side with epoxy and cloth. The inner side of
the hull got epoxy (probably unnecessary) and paint. There was already epoxy
at the filleted and taped corners, so I just kept spreading over the whole
surface. The cabin interior just got paint.
The paper side of MDO really sucks up the resin. I spread two layers of
epoxy before I rolled out the cloth.
BTW, I am mainly referring to 1/2" which is 5 ply and pretty good quality.
The 3/8" is 4 ply with thick inner plys running 45 degrees to each other and
thin outer plys. It is not nearly as strong. i used 3/8" mainly for
cabinetry and the ceiling and cabin top where I wanted to save weight.
I went to a local lumber yard, not H.D. or one of the chains, and spoke with
the contractors' outside sales rep. They usually are more knowledgeable than
the people at the counter or the loaders in the yard. Lots of residential
and commercial builders use MDO for such things as decorative sheathing of
steel porch columns, etc. He was able to order what I needed from their
regular sources and there was no shipping charge. I ordered at four
different times and got MDO from more than one mill. The best was Canadian.
Unfortunately it was a somewhat more expensive due to that ridiculous tarif.
Vince Chew
I thought MDO was the generic term and that different manufacturers
had their own branding, i.e. Crezon, Duralite ,ect
I contacted "Goodfellow" a manufacturer/importer/whoesaler various
ply and lumber www.gdfellow.com when I asked them about MDO, crezone
they directed me to one of their retailers, he in turn offered me one
and two sides with only the one side being stock.
Thanks
Pierre
had their own branding, i.e. Crezon, Duralite ,ect
I contacted "Goodfellow" a manufacturer/importer/whoesaler various
ply and lumber www.gdfellow.com when I asked them about MDO, crezone
they directed me to one of their retailers, he in turn offered me one
and two sides with only the one side being stock.
Thanks
Pierre
--- Inbolger@yahoogroups.com, "chodges31711" <chodges@a...> wrote:
>
> >
> > I think if its good one side, it's Crezon, not MDO.
>
> MDO comes in different grades. Crezon is one.
>
> MDO comes one sided or two sided. If you are painting a sign on
just
> one side and attaching it to a wall, you buy one sided (cheaper).
If
> you want to put it out front with a message on both sides, you buy
> two sided. You can also get it already primed, ready for final
> painting.
>
> With one sided MDO the other side is regular plywood. If you are
> going to glass sheath the outside for protection, glass the ply
side.
> Let the smooth phenolic impregnated paper sheath the inside for
you,
> just prime and paint. Glass on top of the paper side would be a
waste
> except that the smoothness as a base may save some sanding.
>
> My opinion,
> Charles
>MDO comes in different grades. Crezon is one.
> I think if its good one side, it's Crezon, not MDO.
MDO comes one sided or two sided. If you are painting a sign on just
one side and attaching it to a wall, you buy one sided (cheaper). If
you want to put it out front with a message on both sides, you buy
two sided. You can also get it already primed, ready for final
painting.
With one sided MDO the other side is regular plywood. If you are
going to glass sheath the outside for protection, glass the ply side.
Let the smooth phenolic impregnated paper sheath the inside for you,
just prime and paint. Glass on top of the paper side would be a waste
except that the smoothness as a base may save some sanding.
My opinion,
Charles
I could be wrong, after all, "mistaken" is not a condition I'm
totally unfamiliar with, but....
I think if its good one side, it's Crezon, not MDO.
MDO is smooth finished with a paper like coating on both sides,
Creson is smoothish white on one side. Whenever I've been forced to
use Crezon, I've put the bad side facing the interior, to save
finishing time and effort on the exterior.
An earlier post about getting MDO from signmakers is a good tidbit,
that's where I've always found mine. Home Depot, Lowes, etc just give
you a blank stare.
Bruce Hector
totally unfamiliar with, but....
I think if its good one side, it's Crezon, not MDO.
MDO is smooth finished with a paper like coating on both sides,
Creson is smoothish white on one side. Whenever I've been forced to
use Crezon, I've put the bad side facing the interior, to save
finishing time and effort on the exterior.
An earlier post about getting MDO from signmakers is a good tidbit,
that's where I've always found mine. Home Depot, Lowes, etc just give
you a blank stare.
Bruce Hector
I manage to find some MDO "Duralite" good one side. This leaves me
with some question.
If the MDO is "good one side" does the "good side" go on the inside
or outside of the boat?
and the bonus question, what treatment does the "bad side" get, i.e.
Epoxy, glass, ect
regards
Pierre
with some question.
If the MDO is "good one side" does the "good side" go on the inside
or outside of the boat?
and the bonus question, what treatment does the "bad side" get, i.e.
Epoxy, glass, ect
regards
Pierre