Iroko Wood Tearout
This tropical hardwood (a good substitute for teak) can be tough on saw blades and moulder knives. December 1, 2005
We are having trouble with tongue and groove, experiencing tear-out of the grain and inconsistent profiles after 8 lineal feet of production. We are looking for suggestions to fix these issues.
(Solid Wood Machining Forum)
From contributor A:
Although Iroko wood does have a tendency to splinter somewhat like Douglas fir along its edges, I don抰 know why you are getting inconsistent profiles. I just ran about 700 feet of mouldings and didn't have any of that. The worst thing about the stock I worked with was that it was very unstable as far as ripping to width, and tended to warp and bow and twist.
From Dr. Gene Wengert, technical advisor Sawing and Drying Forum:
Note that another name for this wood is Milicia excelsa. This wood will sometimes have lumber pieces with stone-like (calcium carbonate) deposits (very small; check with 10x magnification) in the wood that cause rapid dulling. These deposits may be related to the tree being injured while it is growing. Incidentally, this is good substitute for teak and is often cheaper.
From contributor B:
Do you have the ability to change the hook angle of the tooling, maybe in the range of 12-15 degrees? The doctor makes a good point about the quick dulling of the knives due to the abrasiveness of the product. Also, the smaller the hook angle of the cutterhead, the less life of the knives. Is carbide an option for you? If so, you might look into that option - it will be costly but effective.