Oleg Lego wrote:
The Mark & Juanita entity posted thusly:

On Fri, 21 Jul 2006 23:28:25 -0500, "sweetsawdust"
wrote:

No dust, No screeching, Everything was going smoothly with no problems and
then BANG it happened. I have performed this operation several times with
no problems. This time was a bit different and exciting.

Is it possible there was something inside the wood you were drilling?
Some piece of metal or something else that, not so much causing an
explosion, but something that caught and caused a "kickback" so to speak? I
know you indicate you smelled smoke and charring, but that is sometimes
normal with high speeds and/or dull bits in hard woods.

Something in the wood could also cause a spark. I used to see
occasional sparks from calcium inclusions when cutting teak. No idea
if oak can have the same, though.

Wood can grow around just about anything, including small stones,
grains of sand and so on.

I have to wonder if there wasn't something like a blasing cap (OK,
that would be too big but something like that) in the wood. A dust
explosion will not leave charred wood in the hole.

Here's a really wild hypothesis: Concentrated
NItric acid reacts with celluose to make an explosive (guncotton).
If somebody splashed a little nitric acid on the tree many years
ago then there might have been a little explosive spot in the wood.
I wonder, if you spilled ammonium nitrate fertilizer on a tree,
could it form an inclusion that would go bang fifty years later?

If you didn;t have a posting history, or this was April, I wouldn't
believe the story.

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