Fitting out - wood - ply and MDF
Michael J Wooding
<bill...@gto.net.om> writes
>I had always assumed that THE ply to use when fitting out a boat
>is marine ply.
For internal fitting out Bill true marine ply is considered by many to
be unnecessary. High quality interior grade is OK
>
>I am now hearing that several well known fitter outers use
>exterior grade ply. Any comments?
>
Maybe, but personally I think it not necessary in a modern steel boat,
wooden/elderly iron boat maybe.
>Also is there any form of MDF which could be considered to be
>exterior or marine grade?
NO! - MDF is somewhat deliquescent!
Mike
--
Michael J Wooding - nb DRACO http://www.thewoodings.freeserve.co.uk/
NABO Webmaster http://www.clearlight.com/~nabo
CIBC Webmaster http://www.cutweb.freeserve.co.uk/
The Cutpics site: http://www.vhfcomm.co.uk/cutpics.htm
Michael J Wooding
<delt...@netcomuk.co.uk> writes
>From Michael J Wooding <Mic...@thewoodings.freeserve.co.uk> ...
>
>>NO! - MDF is somewhat deliquescent!
>
>
>Jim Pulling
Behave !
Me :->
Chris N Deuchar
told (by the listmaster no less) so is there a little troll from the desert
here perhaps? :-)
Nevertheless:
Jim Pulling wrote:
> From bill...@gto.net.om (Billyboy) ...
>
> >I had always assumed that THE ply to use when fitting out a boat
> >is marine ply.
> >I am now hearing that several well known fitter outers use
> >exterior grade ply. Any comments?
>
> Nowadays, many (?most) of the narrowboat builders are using blockboard with
> a veneer finish (eg oak) where the wood is seen and exterior ply where it
> isn't (which isn't many places). The blockboard used for carcase
> construction has veneer on both sides. Hull lining is only veneered on one
> side.
I think you meant to say 'oak-faced ply'. Block board is quite a different
animal. It is like a ply wood but the centre layer is far thicker than normal
ply and is made up of lots of lengths of laths 1" x 1/2" or whatever to make
up the thickness. It is generally only an interior material and is only
suitable for where strength is required in one direction only (ie the laths
length should be supported at the ends). Across the laths it is far weaker and
the outer veneers are likely to crack and split open if stressed.
My reply below to the other bits is copied from my original response to the
list can...@ukwaterways.net
For exposed plywood, then there is no substitute for proper BS1088
kite marked marine ply. If it doesn't have a kite mark (or modern
equivalent) refuse it.
For many years I used exterior ply quite happily but within the last few
years the quality (of the adhesive in particular) has deteriorated rapidly
and I have had such ply - from 'reputable' DIY stores like B&Q and
'Doitall' delaminate within weeks when samples were placed in water (an
extreme and probably invalid test) and split and crack within months on
other external uses. Even well, painted three years seems to be the limit
- at least that's how often our 'rolling programme' of replacement of
Herefords cladding seems to work.
Exterior MDF *is* obtainable - but only from the 'real' timber
merchants who normally only supply to the trade. For applications
where strength is not an issue (eg signwork, cabin cladding) it
seems wonderful. As an example, Jan did some signs for a pub a
couple of years ago. Some were in an expensive (ie 'better') exterior ply
and others were in exterior MDF. The MDF ones are perfect, the ply ones
are showing signs of cracking.
I therefore intend to make much more use of exterior MDF in future
and only use exterior ply for the interior and never use interior ply at
all.
Cheers
Chris D
--
Chris N. Deuchar, Nottingham University,
Sutton Bonington Campus, Loughborough, LE12 5RD
tel 0115 951 6264, NEW fax 0870 088 2339
http://www.nottingham.ac.uk/~sbzcd/
Author & Publisher: "A Boaters Guide to BOATING" 3-75GBP +0-75 p&p
A mixture of old and new waterway techniques. ISBN 0 9531512 0 4
Details at: http://www.canals.com/books.htm
DR S NEILL
>>
>>Does that mean you can see it at night?
>>
>>Jim Pulling
>Behave !
>Me :->
Yes but delinquent MDF doesn't behave itself at night!
Sean
Paul E. Bennett
Just for those who are unfamiliar with the term "deliquescent" it means to
disolve in water absorbed from the air (Oxford Concise Dictionary). Whether
MDF has this property is a bit debatable but it certainly will disintigrate
if left, untreated and unprotected, in the open air.
I have seen some quite amazing wood treatments. Some of them claim to be able
to keep wood looking good for a very long time. I think I have found one that
will do so but I am awaiting better proof.
--
Paul E. Bennett ................... <p...@tcontec.demon.co.uk>
Forth based HIDECS Consultancy
Tel: +44 (0)7971-620145
Going Forth Safely
Michael J Wooding
<ed...@csv.warwick.ac.uk> writes
>>>>NO! - MDF is somewhat deliquescent!
>>>
>>>Does that mean you can see it at night?
>>>
>>>Jim Pulling
>
>>Behave !
>
>>Me :->
>
>Yes but delinquent MDF doesn't behave itself at night!
>
I suppose I should have known better !
Mike
Chris N Deuchar
> From Chris N Deuchar <Chris....@nottingham.ac.uk> ...
>
> >I think you meant to say 'oak-faced ply'. Block board is quite a different
> >animal.
>
> No, I meant oak-faced block.
>
> My hull sides and ceiling are oak-faced ply;
> floor and work surface underlay is Far East exterior ply;
> internal bulkheads and carcases are oak-faced block;
> hatch lining is exterior MDF
>
> Jim Pulling
Sounds like Jim "Guinea-pigs 'R' Us" Pulling to me?
:-)
Cheers, (I shall watch with interest)
Paul E. Bennett
bill...@gto.net.om "Billyboy" writes:
> On Wed, 16 Jun 99 18:24:30 GMT, p...@tcontec.demon.co.uk ("Paul E.
> Bennett") wrote:
>
> > I have seen some quite amazing wood treatments. Some of them claim to be
> > able to keep wood looking good for a very long time. I think I have found
> > one that will do so but I am awaiting better proof.
>
> You can't keep us hanging in the air like that!!!!!!
Oh all right then. The product I found quite interesting was "Le Tonkinois",
(I hope I spelt that right) a tree oil based product that is mixed in China.
It is apparently used by the French Navy on some of their craft. It seems
to have a very high penetration into the wood. I am going to be visiting the
local rep in Reading with a few sample bits of wood on which I shall be
setting up some long term testing. I'll let you know what the results are
when they are available (probably next year).
martinp
"Paul E. Bennett" <p...@tcontec.demon.co.uk> wrote in message
news:929656...@tcontec.demon.co.uk...
> In article <37695758...@news.newsguy.com>
> bill...@gto.net.om "Billyboy" writes:
>
> > On Wed, 16 Jun 99 18:24:30 GMT, p...@tcontec.demon.co.uk ("Paul E.
> > Bennett") wrote:
> >
> > > I have seen some quite amazing wood treatments. Some of them claim to
be
> > > able to keep wood looking good for a very long time. I think I have
found
> > > one that will do so but I am awaiting better proof.
> >
> > You can't keep us hanging in the air like that!!!!!!
>
> Oh all right then. The product I found quite interesting was "Le
Tonkinois",
> (I hope I spelt that right) a tree oil based product that is mixed in
China.
> It is apparently used by the French Navy on some of their craft. It seems
> to have a very high penetration into the wood. I am going to be visiting
the
> local rep in Reading with a few sample bits of wood on which I shall be
> setting up some long term testing. I'll let you know what the results are
> when they are available (probably next year).
single component varnish, lasts for years. It contains a lot of UV barrier.
It was the only product in a Dutch ANWB, independent test of all the major
wood treatments, that lasted more than one season in bright sunlight. We
have used it since 1994, on boats and also on our south facing front door.
It is also cheap if not the cheapest available.
Phil Major
J Wooding <Mic...@thewoodings.freeserve.co.uk> writes
>In article <edraa.426...@csv.warwick.ac.uk>, DR S NEILL
><ed...@csv.warwick.ac.uk> writes
>>>>>NO! - MDF is somewhat deliquescent!
>>>>
>>>>Does that mean you can see it at night?
>>>>
>>>>Jim Pulling
>>
>>>Behave !
>>
>>>Me :->
>>
>>Yes but delinquent MDF doesn't behave itself at night!
>>
>>Sean
>
>I suppose I should have known better !
>
>Mike
>
I'm a bit late coming to this subject but 30 years in the timber trade has given
me a little knowledge in this area and currently I stock and sell MDF,Marine
Ply, Exterior Ply, Interior Ply and other sheet materials.
All Exterior ply whether Marine or not uses the same Phenol based glue and
should be stamped WBP (water and boil proof) The main difference between Marine
Ply and Exterior is the make up of the Plies ie individual thickneses of each
veneer and the fact that Marine ply does not allow any core voids which ordinary
Exterior ply does. In Marine ply all cross veneers must butt up tightly and no
knot holes are allowed, this is for obvious reason.
Thier is no difference in the quality of the face veneers, this will stem mainly
from the region that the ply originates from. Most of the Hardwood ply comes
from either Indonesia, (the best very modern plyplants with good sanding
processes,face veneers mostly Meranti, or dry Keruing), Malaysia, (not quite as
good, older plants some meranti but a lot of quite poor keruing,and some pin
holes in most grades, and Brazil (ok but they do tend to play games with grades
and gluelines, and you sometimes get Virola veneer which looks OK but smells of
cats pee!, and no it doesnt go away).
A reputable company like B&Q would stock the right grades and are very
environmentally concious. All hardwood plywoods (when in 8x4 sheet) are marked
in one corner normally with the name of the mill, the country of origin, and
either the words exterior, WBP,MR,or Type1. Exterior wuold generally be OK but
not if followed by the words type1.WBP is what you need to build boats!.MR is
what it says--Moisture resistant ie not waterproof. A good independant Timber
merchant wuold be able to supply the right stuff be careful of some of the
national merchants however staff often lack any real knowledge.
Softwood Plywoods ie Douglas Fir, Elliottis Pine, or Southern Yellow pine all
use proper Phenol glue and are fine for the Floors but the grain is too coarse
for other use.
Blockboard is OK and uses Phenol Glue but is sometime stamped interior, only
because in theory when immersed in water for some time the small core blocks are
of such a size that they could expand and break the glueline.
For every day use Exterior plies with or without face veneers and blockboards
are fine, as are softwood plywoods. they will take wetting no problem, and if
your boat sank and was raised a week later all the plywood would still be
structually sound, if soggy!, however if this happened with MR or Type1 then all
you would have would be apile of loose veneers floating around.
Pricewise marine ply is about 50% higher than Exterior, we love it and the nice
margins it gives us!.
Re exterior MDF this is manufactured by Willamette (used to be Medite) some
house builders use it for Fascia boards which is quite a tough environment, if
you want more information contact them they are in Warrior square Southend but I
do not have thier Phone numbers handy. It would certainly perform OK day to day,
but in a sinking situation I am not so sure. It has only been manufactured about
5 years, so I think it safer to let someone else try it first.
Sorry about this long diatribe,but you now have the full SP --
Phil Major
nb TAIGA at Braunston Marina
Martin E Phillips
<ph...@taiga1.demon.co.uk> writes
>I'm a bit late coming to this subject but 30 years in the timber trade has given
>me a little knowledge in this area and currently I stock and sell MDF,Marine
>Ply, Exterior Ply, Interior Ply and other sheet materials.
<snip>
Looks like a ready-made FAQ.
Wassail!
--
Martin E Phillips http://www.g4cio.demon.co.uk
Homebrewing, black pudding, boats, morris dancing, ham radio and more!
Michael J Wooding
>Phil Major
>nb TAIGA at Braunston Marina
No problem for me Phil - many thanks for the useful info.
Malcolm Nixon
<mar...@g4cio.demon.co.uk> wrote:
> In article <ptqXvHAI...@taiga1.demon.co.uk>, Phil Major
> <ph...@taiga1.demon.co.uk> writes
> >I'm a bit late coming to this subject but 30 years in the timber trade has given
> >me a little knowledge in this area and currently I stock and sell MDF,Marine
> >Ply, Exterior Ply, Interior Ply and other sheet materials.
>
> <snip>
>
> Looks like a ready-made FAQ.
>
My thoughts exactly - I think Phils posting wins the best of the
week prize - many thanks
--
Malcolm, (remove the X to reply )
Steam narrowboat President's website -last update 19/6/99
http://www.users.surfaid.org/~nixonm/president/p_home.html
President on TV - Songs of Praise Sunday 27th June
Brian J Goggin
<ph...@taiga1.demon.co.uk> wrote:
[...]
>I'm a bit late coming to this subject but 30 years in the timber trade has given
>me a little knowledge in this area and currently I stock and sell MDF,Marine
>Ply, Exterior Ply, Interior Ply and other sheet materials.
[...]
Great stuff. Many thanks.
bjg
Adrian Stott
adr...@enable.telinco.com
Tel. +44-956-299966 (from UK, 0956-299966)
martinp wrote in message <7kfmcg$72e$1...@news.worldonline.nl>...
>
>> Oh all right then. The product I found quite interesting was "Le
>Tonkinois",
>> (I hope I spelt that right) a tree oil based product that is mixed in
>China.
>> It is apparently used by the French Navy on some of their craft. It seems
>> to have a very high penetration into the wood. I am going to be visiting
>the
>> local rep in Reading with a few sample bits of wood on which I shall be
>> setting up some long term testing. I'll let you know what the results are
>> when they are available (probably next year).
>Epiphanes Hard Hout Olie - Hard wood Oil, which in fact is an old fashioned
>single component varnish, lasts for years. It contains a lot of UV barrier.
>It was the only product in a Dutch ANWB, independent test of all the major
>wood treatments, that lasted more than one season in bright sunlight. We
>have used it since 1994, on boats and also on our south facing front door.
>It is also cheap if not the cheapest available.
>
well. It is Ronseal Hardwood Garden Furniture Protector. Still a little
hard to find even at the larger DIY places which sell other wood
preservatives and Ronseal products. But I think Ronseal spent a lot of
research money on designing it, and my teak is still golden coloured whereas
by now with teak oil or other it would be grey. And because it is not a
varnish, it never peels, and it is not a stain, so it doesn't hide the
natural colour or grain of the wood. Nice spec., I thought.
Adrian
Phil Major
<delt...@netcomuk.co.uk> writes
>From Phil Major <ph...@taiga1.demon.co.uk> ...
>
><snip splendidly informative stuff>
>
>Thank you for all this.
>
>Please can you advise why marine ply somehow seems to have a nicer looking
>finish which often appears to be of 'show' quality and grain-wise is often
>well-matched between different 8 x 4 sheets.
>
>Also where does so-called furniture-ply fit in this?
>
>Jim Pulling
sorry for delay but I am working away at present and only get to read the News
group occasionally. Re better veneers on Marine ply I am not aware that the
mills select special veneers for MP, but only the best Mills would produce MP
and perhaps being a premium product they do a bit of selection.
I'll check comparative costs but I suspect you will pay more for a sheet of MP
than a normal WBP ply with a decorative veneer face ie Oak, Ash, so why bother?
Thanks for you comments everyone, as I say I do not get on the Newsgroup very
often at present, but any other Queries re Ply or Softwoods, ie Species and
availability of product,put them on the group and I will answer ASAP