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train kiln issues 'the wood', "pallets" and what they're made of:

updated sat 9 mar 02


Philip Poburka on fri 8 mar 02

Ahhh...just this note:

'Pallets' may be and are made of any kind of Wood as had gone into them.

My impression from having looked at pallets, is that they are made of
'scrub' or other Wood as likely comes from eclectic Trees being removed from
land being cleared, or where the size and species or condition of the Trees
as well as their species-numbers does
not recommend them to other more remunerative commercial destinies.

If 'Poison-Oak', 'Poison-Ivy' or 'Poison Sumac' grew to thick enough
section, they'd make pallets outta them too.

Pallets appear mostly to be made from 'Green' woods which Season in situ as
pallet elements, distorting and shrinking as they may in that configuration.

I heat my shop with a big Wood Burning Stove whose principal fuel is
Hardwood pallets.

I slice 'em up with a 'Skill-Saw' usually, and wince when I spoil or detooth
a nice Carbide Blade with the occasional unexpected or unseen Nail, Screw,
Staple or other nasty, as may (and inexorably will) be lurking.

I have had Cherry, Various Oaks, Mahogany, Elm, Ash, Sycamore, Butternut,
Walnut, Pecan, Hickory, Beech, Maple (both 'Hard' and 'Soft'...)
Campher-Wood (once!) and assorted (to me) 'ambiguous' Pacific Rim or other
Equatorial species I do not know or recognise.

I have had all manner of Pine, 'Pitch-Pine', Sugar Pine, yellow Pine and
Spruce...Doug-Fir, 'Hem-Fir' and whatever else as is more or less in that
balliwick of Conifers as I maybe do not distinguish too keenly from

I avoid the 'Softwood' ones when I can, but will use them if desperate,
preferring the 'Hardwood' ones.
Generally, the heat one will get is greater and or more prolonged with
Hardwoods, and there is less soot or other, which 'soot' tends in my case,
to clog the screen I have over the top of my flue (as a 'spark arrester'),
clogging then obliges the Stove to choke up and fill my Shop with smoke,
obligeing me to ascend the roof and ammend matters...

The difference between 'softwood' and 'hardwood' becomes easy enough to
espye with some little practice, and the distinction traditionally of the
term, lay in
whether the Tree is deciduous or not.

Trees whose 'leaves' (needles or what) remain all year long are deemed
as all the Pines, Firs, Cyprus and 'Evergreens' so to speak.
Some Softwoods may be 'harder', denser or heavier than some
'Balsa-wood' is a 'Hardwood'...

Whilst those trees who dispense with their leaves in Winter , as the Oak -
and all the 'Nut'
Woods,The Cherry - and all the 'fruitwoods', and as Ash, Mahogany, etc etc,
are called deciduous, and are traditionally designated 'Hardwoods'.

Deciduous Trees who are pleased to grow in mild or consistantly warm climes
may not actually be disposed to trouble themselves to dispense with their
seasonally, but
remain none-the-less understood to be Hardwoods whether they exercise their
talents of deciduosity or not.

Hardwoods are understood to give more and longer heat for their volume than
do Softwoods, and
usually are found to be more dense or heavy, excludeing the moisture either
may have to them at that moment of examination.

Moist wood will allways feel cool to the touch, or to the cheek or lips, as
one may,
and too the terms 'dry' or 'kiln-dried' especially, being relative terms.

Kiln dry means it were brutally rushed through a 'drying' process usually
being saturated with Steam and some chemicals, and thence persecuted to a
subsequent heat dessication, not so much to 'dry' the wood as to stabalize
it, or
save it the time and troubles of those distortions normally associated with
drying out from the 'green' state...

Distortions which to some degree, it will then be pleased to do anyway at
it's liesure, and is stated to have been to a certain dryness when it
left the kiln...who knows what dryness it may have some while after that, as
it absorb whatever moisture from the Air or other as it may be wont to do,
and will do.

'Kiln-Drying' is an Industrial or Commercial time-saver that
accomplishes a poorer version of what letting the Wood dry out at it's own
pace would have done.
Nothing more....other than stinky chemicals being often pumped into the
Kiln-Dried product which bye happier or 'Natural' means (ie just letting it
dry...) it would not have had.

Lastly, those pallets which have been allowed to soak up 'PCB's or (if
older) 'DDT' , or other sundry and maybe not-so-sundry chemicals as may be
and WILL be now and again spilled on them, will likely liberate some
heat-affected version
of those pesky Chemicals when being burned.

I have heard more than once of people getting woozey, sick, mighty sick, or
from such mis-hap.

I have found a few times that I was not feeling quite so perky as I might
otherwise have, oweing - I supposed - to the discrete waft or other of some
unknown nastiness in pallets I am burning.
Generally I run my stove in a way thet you could burn about anything in it
and not smell a hint, as I like a good draw and regulate it for effecient
aspiration and heat.

But be aware of this...for what it's worth!

Las Vegas

Where it DOES get 'cold' enough to freeze the water in the kitchen sink now
and then, and where 'pallets' make a happy difference to that sort of thing.

----- Original Message -----
From: "Julie Milazzo"
Sent: Thursday, March 07, 2002 8:24 AM
Subject: Re: Train Kiln issues 'the wood'

> Hey Marv and Kevin, I don't know what pallets are made
> of, but I did a few pit firings two years ago, and
> noticed a huge difference in result when I switched
> from softwood (pine) to hardwood, like cherry or oak.
> That switch upped the temperature enough to get the
> copper to work it's magic, whereas previously I
> couldn't even get glue to burn off of the pieces...
> Good luck! Jules
> --- "MOORE, Robert J."
> wrote:
> > Marvin, there was a thread a week or two ago on here
> > about the importance of
> > dry wood while wood firing. Check out the archives,
> > there are several posts.
> > On this point alone your temperature should be
> > better using dryer wood. You
> > may even want to combine cured wood w/ the wood you
> > are using.
> > Other possible places to get scrap, wood flooring
> > manufacturers, Sawmills,
> > or anyplace making wood products in volume.
> >
> >
> > -----Original Message-----
> > From: Marvin Bjurlin [mailto:bjurlin@FREDONIA.EDU]
> > Sent: Wednesday, March 06, 2002 5:36 PM
> > Subject: Train Kiln issues
> >
> >
> > fellow wood firers,
> > i am an undergrad at SUNY Fredonia NY, who has
> > recently built a train
> > kiln from brick taken from an old salt kiln. The
> > condition of the
> > bricks reflect my recent attempts at reaching
> > temperature - poor. its
> > loose stacked two hard bricks thick in the walls to
> > the basic
> > proportions of the Neely design. its covered with a
> > homemade castable
> > material to seal in air and heat. i have a few
> > questions for whomever
> > may be inclined to answer:
> >
> > What basic rules of thumb are there involving the
> > stacking configuration
> > of the pots to promote airflow?
> >
> > our chimney is currently 12 ft high from the ground
> > and we're planning
> > on adding 4ft of pipe to increase the draft, any
> > suggestions? our
> > stacking chamber is 5 ft. long by 2ft wide by 3 ft.
> > tall.
> >
> > were stoking from one side onto the grate with alot
> > of flame licking out
> > making this a toasty chore. are there any
> > suggestions for any
> > alternative way to feed the fire?
> >
> > are there any basic wood firing principles
> > conscerning the airflow into
> > the kiln vs. the air flow out?
> >
> > we burn hard wood rippings from a local pallete
> > company. all of it is
> > unseasoned green stuff. does this have anything to
> > do with our troubles?
> >
> > we have a damper located in the chimney above the
> > chamber. The proper
> > use of this during certain stages in the firing is
> > still a mystery. any
> > suggestions?
> >
> > do we need to force air into the firebox?
> >
> > all helpful hints are much appreciated,
> > kevin
> >
> >
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