Oak close up

[fredbelknap]

This may be interesting to you guys. It is a ultra close up of a piece of oak. Bet Dick could do that if he really wanted to.
community.woodmagazine.com/t5/General-Woodworking/Electron-beam-images-of-Oak/td-p/37206

Hope it is alright to link to another forum.

[larryh86gt]

That's neat. It sure splains why painted oak is so hard to refinish.

[Leo Voisine]

AWESOME

As an engineer myself that looks at those electron microscope scans of metals - I have always wondered what wood would look like.

Considering what those microscopes are capable of - those are about as low a magnification as they go.

Looking at metals - they can "see" the metal on an elemental level.

Now we can CLEARLY see why humidity can so dramatically affect the expension of wood.

Sure that is oak - which we know is porous - but even the most tight grained wood is filled with air spaces and cavities.

I will print out those pics later and put them in my shop notes notebook.

[sawduster]

Though he doesn't say it, I'm thinking that is white oak, which is real porous via end grain, but very little through long grain. We've made barrels of white oak for hundreds of years because of that.

Some very cool pics. Thanks for posting.

[dcarter636]

A simple experiment to try during an idle moment:

Cross cut a thin slice (1/8" thick or so) from a straight grained oak board.

Hold the wafer up to a light and you can appreciate why open pored oak was used a filter medium at one time.

[Ruffnek]

or,

cut a piece of Red Oak 3 or 4 inches long and 1" square. Place one end in a glass of water and blow into the other end...hard.

You will see air bubbles formed at the end inside the water.

As several people commented on the WOOD forum, I'd like to see the Oak pics alongside something like Hard Maple just for a comparison.

[TDHofstetter]

The most amazing part of it, in my mind... is that although THAT porous, it's still amazingly rugged stuff.