Tablesaw Issue

[Jeff Bartley]

Jack,
Problem with lumber like this is that even after it's processed it will likely still move. Depending on its use this can be no big deal or catastrophic in a finished piece.
If you decide you can continue to use this lumber I would use a bandsaw to process it from rough. Reaching past the blade on a tablesaw, riving knife or not, seems like a bad idea!

[Al Launier]

Unless I missed this above I'm curious what the tooth count is on the blade you've been using...24?

[Jack Frederick 135]

I have been running Diablo 10 in. x 40-Tooth General Purpose Saw Blades

[Richard Coers]

The next time you apply paste wax to the table and rip fence, apply some wax to the riving knife as well. It really helps. You might also change hardwood suppliers, the place you use is not the best at kiln work.

[Michelle Rich]

yes, wood stress, check fence for parallel, and when this happens to me, I stop the saw, pull out the wood...turn it end over end, and start cutting from the other end. Most times this works. A real stubborn board will jam again, but most won't

[Peter Christensen]

I would advise you clamp a board to the front half of the fence stopping at the front of the blade when you rip. Basically making a European style rip fence. This time the wood was pinching. Next time the internal stresses could cause the wood to spread. With the long North American fence the spreading wood can pinch the blade, possible kicking back. Get a dedicated ripping blade rather than the combination blade. They work way better.

[Tom Bender]

I always have a few small wooden wedges handy for a lot of purposes. They are easy to make on a sled. Grab an offcut of Maple or similar 1/2" thick and at least 6" wide and 3" long. Prop it away from the fence 1/2" at the end that is 6" from the blade and cut one off. Remove the prop and cut the next one. Make a few, sand and wax.

[Tony Bilello]

This has absolutely nothing to so with your saw, fence, blade or anything other than the fact the wood is under stress. probably that slab was taken from an area near a crotch.
I would relegate that piece to the wood pile because there is no predicting what it might do in the future as a furniture piece.

[Gordon Stump]

I religiously use a power feeder now to rip thick hardwood. Sometimes a stressed board can kick back and hit a feller in the stomach and cause that feller internal bleeding. Do not ask me how I know this!

[Günter VögelBerg]

It sounds like the wood may be "case hardened". If that's the case the solution is a different wood supplier.

[Dustin Bullard]

I spotted elsewhere that the Freud Diablo blades now come in a super thin kerf option...

A regular kerf blade is 1/8in = .125"
A thin Kerf blade is 3/32 = .0937
The Diablo D1040X (10" General Purpose Blade) should have a kerf of .098 so it should be ok...

However, they sell a 10.25" General Purpose blade with a kerf of .079 and if you somehow ended up with a 10.25" blade it would probably fit on your saw and absolutely explain your issue...

Everyone else here is on point, its probably just unstable wood under stress and your blade is just fine but its still worth taking a peek at the blade... If you can, see if you can track down some calipers and check the thickness of the teeth on your blade as well as the kerfs it cuts and finally the thickness of your riving knife...

I do want to mention that I also use the Diablo 10" general purpose blade as my "I'm not so sure about this piece of wood blade" and save my nice blades for other things and I've never had an issue...

[Marc Jeske]

A great example of a situation for a knee bump off switch.

Marc

[lowell holmes]

Another alternative is :

https://images.search.yahoo.com/sear...-web&fr=mcafee

[Rich Aldrich]

When not properly stress relieved during the kiln drying, the wood will either pinch the blade or try to spread out after cutting.

I work at a hardwood lumber and veneer plant. Lumber is stress relieve at the end of the kiln dry cycle. The process our kiln dry operator uses is really good for stress relieving and our customers are very happy with the minimal issues with stress when using the wood. I cant go into the details, but I really doubt that it is an industry secret. Some plants don't want to spend the extra time or money to stress relieve. Steam is used to dry the wood.

Our daily production is about 70,000 bdft per day with a 400,000 bdft predryer and 400,000 bdft kiln drying capacity (10 kilns at 40,000 bdft max). Hard maple, soft maple, oak, birch, cherry, beech, and ash are the primary species.

I had a guy with a dehydrating kiln drying process dry 650 bdft and it was really good.

[Tom Welch]

Jack, is your blade a full kerf? like 1/8"? If your running a thin kerf blade like the ones that the box stores sell, then your blade is not opening up the kerf wide enough for your riving knife. You do need a full kerf blade for that riving knife. That said the above condition can still happen with the right set up. But if your set up is correct, you lessen the chance and can avoid problems unless your wood does have a lot of stress in it. Also I would recommend a ripping blade for thick hard woods, but the combo blade can do it, but you sometimes have to rip slower. I do use a Woodworker 2 combo blade, but mine is full kerf. When ripping thick or hard maple I do favor installing my 24 tooth rip blade.