Bubinga BANG!

[Bill Wyko]

I was bandsawing a piece of 4/4 Bubinga in 1/2. It was about 10 inches long and 6 inches wide. When I got to the end of the cut it looked perfect. Then in the last 1/8th inch it goes POP and warped into a twist I could open a wine bottle with. I tried again and the same thing. everything looked perfect until the end and BANG an instant cork screw. Any Ideas? It was perfectly flat before the cut.:mad:

[Bruce Shiverdecker]

That is caused in "Tension " in the wood. When you cut it, the tension was relaesed, and it corkscrewed. This can happen to any wood.

Bruce

[Peter Quinn]

I think its the trees way of protecting itself form over harvesting. Like instant karma, cellulose style. The tree is thinking "Oh, so you think you can flatten me huh? We'll just see about that!"

May I suggest a different board or a very uniquely curved work piece?

[Nate Rogers]

It happens all the time, I certainly can't seem to tell what piece will and what one won't...

Nate

[Bill Wyko]

I think its the trees way of protecting itself form over harvesting. Like instant karma, cellulose style. The tree is thinking "Oh, so you think you can flatten me huh? We'll just see about that!"

May I suggest a different board or a very uniquely curved work piece?
I still won in the end:D I cut them into smaller pieces, jointed them and glued them back together and drum sanded them. Scared the bejillies out of me when it happened though:eek:

[John Thompson]

Ditto Bruce and tension.. same thing happens on a TS, but it it not as pronounced as you mentioned as the stock is thinner on the TS as 10" saws generally have a max 4" depth..

Sarge..

[Jim King]

This is many (most ?) times the result of an inexperienced kiln operator.

[Brian Kerley]

Bill, if any of that bubinga that you've been gloating about for the past few weeks gets to be too much of a handful, I might be convinced to come down there to Tucson and take it off your hands for you :D

Heck, I wouldn't even charge you for my trouble

[Bill Wyko]

Do you think it will relax over time? That was a lot of stored energy.:o I'm worried about the giant slab I have. If I start to cut that thing and it does that, there goes some big money. That piece is 87 sq ft. It'll probably sit around for years before I build anything with it though.

[Tim Malyszko]

If I start to cut that thing and it does that, there goes some big money. That piece is 87 sq ft. It'll probably sit around for years before I build anything with it though.

Is that some of the waterfall bubinga? There was a slab at our local Rockler, but $2 grand was a little more than I wanted to spend on a slab of wood:eek:.

[Chris Padilla]

Be glad it happend on the BS and not the TS. That is one reason why I do most of my ripping on the BS now...tends to keep the underwear cleaner! :D

[Bill Wyko]

Is that some of the waterfall bubinga? There was a slab at our local Rockler, but $2 grand was a little more than I wanted to spend on a slab of wood:eek:.
Yes it is. This piece was around 1800.00:(

[Glenn Clabo]

Well Bill...sorry to say...it ain't gonna spring back. I seem to remember that it's wood cut from a "leaning" tree...and it isn't going to un-lean.

More...
From Wikipedia, the free encyclopedia



Reaction wood is formed in response to mechanical stress, and helps to position newly formed parts of the plant (http://en.wikipedia.org/wiki/Plant) in an optimal position. Reaction wood forms when a woody plant (http://en.wikipedia.org/wiki/Plant) part is subjected to mechanical stress. This stress may be the result of wind (http://en.wikipedia.org/wiki/Wind) exposure, excess of snow (http://en.wikipedia.org/wiki/Snow), soil movement, etc. The reaction wood appear as asymmetric growth. The cambium (http://en.wikipedia.org/wiki/Cambium) in the affected part of the trunk is more active on one side, leading to thicker growth rings. Branches practically always have reaction wood, since they need support to maintain their horizontal or nearly horizontal position. There are two different types of reaction wood, which represent two different approaches to the same problem by these groups of plants (http://en.wikipedia.org/wiki/Plant):

In angiosperms (http://en.wikipedia.org/wiki/Angiosperms) reaction wood is called tension wood. Tension wood forms above the affected part of the plant, pulling it up. It is composed almost entirely of cellulose (http://en.wikipedia.org/wiki/Cellulose).
In conifers (http://en.wikipedia.org/wiki/Conifers) it is called compression wood. Compression wood forms below the bent part, pushing it up. Compression wood is rich in lignin (http://en.wikipedia.org/wiki/Lignin).As a rule, reaction wood is undesirable in any commercial application, primarily as its mechanical properties are different. Reaction wood is hard, brittle and it breaks the uniformity of timber. It also responds differently to changes in moisture.

[Bill Wyko]

Thanks Glen. Do you think if I let it sit around for a long time it will relax? Otherwise I'll vac press it to a substraight.:D That'll pull it into place.

[Glenn Clabo]

Well Bill...Only old guys, like me, can sit around and relax.;)

[Bill Wyko]

I have a hard time relaxing too. Here's my latest relaxation device. I call it my Festool rapid transport system.

[Roger Bull]

I had the same thing happen a bit ago with some of the Bubinga from WoodWorkers Source (prior to these recent shipments). It was really dry but still not stable.

Here is the thread:
http://sawmillcreek.org/showthread.php?t=77690

Peter Quinn posted a funny story. You can probably relate to it too.

I tried a few things to straighten the pieces but not much helped. Steam and water worked temporarily but went pretty much back to the wild look as it dried.

The ones that were not too bad got fed to the drum sander and after a couple more months stacked and stickered they seem stable.

Some pieces I laminated to use in other areas. Those also seem stable now.

Good luck.
-Roger