Need info on what type of wood to use ?

[macurtis]

Stopped by a used equipment dealer today to drop off some
cards. I gave them to lady behind desk and explained to her
what I did. I was fixing to get in my truck when this man
came running out the door, the owner, I thought he did not
want me to leave the cards. He said he had been looking for
someone to furnish some boards for his equipment trailers.
He hauls everything from dozers to farm implements and
tractors. My question--What would be the best wood to put
on these trailers--all 2x . Wide or narrow? Be careful where
you drop off cards, you might get a saw job!

[Bud Man]

Macurtis --Try -Osage Orange, Cottonwood, Gum Heartwood, White Oak, Cull Hickory, Ash --Someone else will come along with some  more.

[Tom]

The favorite down here for tracked vehicles is Live Oak (generally 3 inch) because it is so tough.  It is one of the white oaks.

For wheeled vehicles it is Treated Southern Yellow Pine.

[Tom]

Here is what Trc^ had to say on a duplicate thread.

The best from what ive seen would be steel plate  ... ..

Not sure about best but usually 2x8's are used .. some times 2x6's .. if have it and the customer will go for it I think a good hardwood like oak probably be real good

Trc^

[macurtis]

Tom----How much should I oversize the timbers?
He wants to let them dry before putting the on--
or could we put them on wet?

Thanks

[Tom]

If he is used to using dressed wood (boards go in channel iron) then cut the 2x minus the saw kerf.  you just use the inch scale and put it on  the inch.  It will dry close to a dressed size and can be dressed to size with a hatchet if you have too.  If it is a deck that doesn't fit inside of channel iron then it won't matter.  I would cut it a full 2 inch or inch and an eighth.  Shrinkage will depend a lot on the direction of the grain in the board so there is not a good answer.

If you make it out of white oak or any hardwood then you would be better off putting it down green. That stuff gets hard when dry.

Treated pine has to be dried to treat it and can be put down wet from the treatment plant if you aren't concerned with opening up cracks.  They don't hurt anything and let water and dirt fall through.  If you don't want cracks then the treated wood should be dried again.

Note: 3 inch or better is used for tracked vehicles because the tracks erode the wood not because they weigh any more.

[Bibbyman]

Make sure you have a source and a price for good long logs before you give him a quote on the price.  

Up here, most everyone wants white oak for decking.  And clear white oak logs 16’-20’ long can be expensive and hard to come by.  You saw into one and hit a rotten spot in the middle and you’ve loss all profit or fallen into the red.

Then you got to figure not all the log will make nice, wide, full length boards so you'll have to find a buyer for them or eat them.

[Frank_Pender]

Out here in Oregon, Our Oak is so hard that  some of the guys would rather have Douglas Fir for the beaver tail ramps and decking as the grousers cannot grab hold enough to climb the tail of the trailer.  If the trailer is a full tilt they sure cannot get started on such a hard wood.  For the Low Boys most of my customers prefer the Oak as they are often getting on and off on the side as opposed to a steep incline.  some have the trailers that drop off the 5th wheel plate and unload forward and they too prefer the Oak. Most all of them install the material when it is green so as when it dries and get wet again and expands it does not buckel.  It merely expands to the point of when it was green.  The best of luck in you cutting ventures.

[ARKANSAWYER]

Macurtis,
 Sycamore works well and it tough to boot.  It and white oak will need to be sawed 8 3/8 inches wide to dry to 8 inches.  1 3/4 thick dries down enough to get into most trailers deck rails and is plenty strong.  Boards wider then 8 inches gets to cracking and warping to much. plus get  very heavy to handle.  Bugs like hickory and ash to well for it to last long unless coated with oil.  Q saw  the sycamore and they will not want to park a dozer on it.  Also figure your price for square feet of decking as it is easier for them to figure out what they need.  IE  My trailer deck is  8x22 ft or 176 sq ft and I sell trailer deck for $1.00 a sq ft so it would cost $176.00 for 2x8's to do it.  That is about 350 bdft of lumber that I get roughly $0.50 bdft for any way.
ARKANSAWYER

[Jeff]

Our Trailer beds on the flat beds and lowboys are all white oak.  If we have to replace them they are installed green because of the aforementioned reason by Frank. We also, and I doubt if this is very environmentally agreeable, use drain oil to thoroughly soak the lumber once it is installed. If it starts looking dry we soak it again.  

One of the reasons we do this would not be what you expect. Ice don't stick to it as well. After an ice storm you can get up there and just push it off, where with raw wood, it becomes part of the wood till it thaws.

[Corley5]

My uncle prefers big tooth aspen on his low boy.  It's soft enough to get some traction as Frank mentioned.  He puts it on dry then soaks it up with used oil so it lasts longer.  We've got a beech deck on our trailer that's been on it for 8 years and has held up good.

[woodmills1]

most of the trailer decking i cut is oak, some white, but most red, as that is the predominate tree around here.  i cut full 2 inch but will special to what ever a customer wants.  i get around a buck per bd ft as the logs usually don't come in under 50 cents.  i have cut hemlock for customers who want a little less weight, but watch out for splinters they are very painful and usually get infected.

[L. Wakefield]

   What do you notice on the oil-soaked boards in the rain as relates to traction? Does the rough cut compensate for the slick of the oil?   lw

[L. Wakefield]

snip

Shrinkage will depend a lot on the direction of the grain in the board so there is not a good answer.

snip

  Hey Tom, eddicate me on this one- I sense a larnin opportunity. I picture wood if it's ripped as mainly having the grain go vertically, in which case if I take your meaning correctly I might expect shrink mostly in the vertical direction. (Now of course, that I think about it I've seen mongo shrink in the crossways direction.) How does shrink relate to grain, then, and what variation can you see in the 'direction of the grain' of (I would assume) ripped boards (cuz if you are getting dimensional lumber by cross-cutting I don't know where your forest might be...trees 8-16 ft in diamater, and chainsaws with 8ft bars..Babe the bleu ox is out there somewhere   )?   lw

[Tom]

LW,

A sawyer has an opportunity to go after grain configurations if the log is large enough.  Some configurations work better for a special application than other configuratios.  Basically there are two.  Flat sawed= grain runs the width of the board  Quarter sawed or Vertical Grain= the grain runs vertical to the wide face of the board.  Bastard grain lies between the two.

Here is a commonly seen diagram of the shrinkage of designs as they are taken from different grain directions.  The grain has more to do with the shrinkage than the shape of the piece.

Longitudinal shrinkage(parallel to the grain) is quite small.
Reaction wood tends to shrink accessively parallel to the grain.
Wood from near the center of a tree (juvenile wood) shrinks accessively lengthwise.
Wood with cross grain exhibits encreased shrinkage along the longitudinal axis of the piece.



Wood is an anisotropic material with respect to shrinkage characteristics.  It shrinks most in the direction of the annual growth rings (tangentially), about one-half as much across the rings (radially), and only slightly along the grain (longitudinally).  The combined effects of radial and tangential shrinkage can distort the shape of wood pieces because of the difference in shrinkage and the curvature of annual rings.  

This is a paraphrased excerpt from the Wood Handbook: Wood as an Engineering material. (U. S. Gov. Printing office 1987)

Longitudinal drying defects as related to the grain:

** Tom's rule of thumb:
            " wood tends to bend toward the Bark".

[L. Wakefield]

   oboy. There are some synonyms in there that I'm going to have to hunt down. That 1987 handbook is clearly one of the fundamental texts I really want.

  I'd heard the term 'cross-grained S O B' (not complimentary..). From your nomenclature it sounds like there's another wood-based term that would do as appropriately.

  I see a little bit where your 'reaction wood' would fit into this. I appreciate the time you took to sketch this out. I should look to see if there's something like it in the 'online toolbox', cuz that wood be a good place for it too.  lw

[Tom]

I thought I had listed this link but maybe not.  Here is the wood handbook and more information than a young feller' can digest in a month of sundays

http://www.fpl.fs.fed.us/documnts/FPLGTR/fplgtr113/fplgtr113.htm

[macurtis]

  Tom, I sure do appreciate the information.
Where else can you get info like this and put it in words
a new mill owner can understand, I say you can't!!!!!
Thanks

[Don P]

Sorry I got thinkin all chemikly
Going all the way back to wood as long strands of polymer cellulose got me thinking about Tom's picture of crook.
To me that is a classic quartersawn board after drying. It's the left center board on the log end drawing, here's what happens.

The cell walls are made up of fibers of cellulose. As moisture(bound water, actually just H's and O's) leaves bonding sites on the cellulose chain the fibers of cellulose (red in my drawing) have room to move closer together. This is shrinkage. The angle of the microfibers of cellulose wrapped around the cell wall determines the direction the shrinkage will take.

Juvenile wood contains cells wrapped by fibers of cellulose at up to a 45% angle, a cell like this will shrink considerably lengthwise. A mature cell wall will contain microfibril angles closer to 5 degrees from vertical, it's shrinkage would be mostly in width.

Back to the crooked quartersawn board. If the right side is the heart containing juvenile cells that shrink lengthwise and the left side contains cells that don't, the board in drying will be pulled shorter on the heart side, or crooked.

In my drawing I tried to show that the MFA doesn't pick a certain time to become vertical but slowly becomes more vertical over time. Another fact I tripped over on the way somewhere, heartwood is not all the same. The deposition of extractives is pretty erratic and low quality the first few years of heartwood production,then it levels off. The least durable heartwood is at the heart :-/.

Saw quartersawn a little thicker if your pushing the planing tolerance tight. The thickness of quartersawn is tangential in direction, its thickness is where most shrinkage occurs.

[Don P]

As long as I'm off in the textbooks again . After the reaction thread I was reading up on it and alot of the same forces are at play...Here's my book report

Reaction Wood

Reaction wood is formed when, for some reason, the main stem of the tree is not vertical. It is the wood formed by the tree in trying to right itself. In softwoods compression wood is formed on the underside of the leaning stem. In hardwoods tension wood is formed on the upper side. If the center of the stem is considered the point of rotation, compression wood is pushing up on the stem or tension wood is pulling the stem upright. Imagine pulling on a stem, the bottom, compression, side would become shorter as the upper, tension, side would lengthen. I find this analogy helps me understand other characteristics of this wood.

Compression Wood

The underside of most branchwood is compression wood, holding up the branch. Weeping or drooping branches would be an exception. Compression wood contains more lignin and less cellulose than normal mature wood. Lignin is what makes cells stiff, or strong as in a strong column. Individual compression wood cells, or tracheids, are typically shorter by almost a third, blunt or even folded on the ends, and rounder in section. It is normally about equal in strength to normal wood, although denser. Compression wood shrinks about ten times more lengthwise than normal wood, 1-2% vs 0.1-0.2%, this is its major drawback. Compression wood tracheid walls typically contain a primary later of somewhat random microfibrils followed by the fairly horizontal S-1 layer, this is relatively normal. The major ply of the cell wall, the S-2 layer, that controls most properties such as shrinkage, lays at a much flatter angle than normal. As bound water leaves the spaces between the microfibrils and they draw closer to one another this causes more lengthwise shrinkage than in cells having a more vertical microfiber angle.

Tension Wood

Tension wood is trying to right the stem from the upper side of the pith, by pulling on, or restraining, it. Tension wood is low in lignin, high in cellulose. Cellulose is the long, straight chained, glucose polymer in wood. This makes a cell that is strong but supple. This analogy can only be taken so far as in reality tension wood is weaker than normal wood, so should not be used in critical structural applications. In cross section tension wood cells walls are thicker than normal, often with the inner secondary cell walls detached from the primary layer. In the secondary layers is an abnormal, thick, gelatinous layer. The fibers in this layer are arranged nearly vertically. Again the analogy of the cable being pulled taught with fibers straightened out or pushed to a flatter angle as in compression wood. Often this gelatinous, or G, layer us pulled loose out of the "shell" of the primary cell wall and dangles there as a tough fibrous "fuzz" that heats saw blades and makes a flat smooth finish very hard to attain. Shrinkage is high in tension wood but for a different reason than in compression wood. Since the inner layers of the cell wall detach so frequently the orientation of the primary layers' microfibrils determines the direction shrinkage will take. This is typically a more horizontal angle than that in the secondary lamellae of normal wood, so the longitudinal shrinkage in tension wood is greater than in normal, although normally about half that of compression wood.