Straightening a board
If you have a 3/4" X 8" X 8' piece of oak that has a bow in it, and all you have is your table saw to straighten it, do you typically cut the cupped side first, or the bowed side?

Thanks  Greg
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I'd probably clamp the straightest 2x4 I had to it and do it with a circular saw. If it had to be done on the table saw, I'd screw said 2x4 into the cupped ends to run across the fence as a reference.
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O.k., first can we determine if the board has a bow or crook (as a reference, let's just use wiki;

If it's a crook you're going to need a straight edge to run against the fence. The board doesn't have a straight edge so you're going to have to make it straight (jointer, hand or power plane, skilsaw) or attach a straight edge to go right to the T.S.. This could be a long sled or just another straight board with 2 or 3 screws to keep it place either on top or underneath depending on width. Just be forewarned that when you rip that oak down the middle you might not have any straight edges. 

If it's straight but cupped, I rip a little wide with concave side up. then I move the fence a wisker closer, flip the board and rip with convex side up to remove the slight bevel, then move the fence another wisker and rip the other side. This procedure gives me reasonably acceptable square edges even though the board still has a portion of the cup remaining. (Although, same as above, it may not still be straight.)

If the board has a twist (what most generally call warped), good luck. With a cup, you can usually rip into several pieces, flip a few, reglue, and end up with something relatively flat. Not so with a twist. You can still rip it into several pieces, but flip them over, flip them end for end, or spin them around, and every piece will still have the twist in the same orientation. If you do glue it back together, you'll have the same twist but the grain pattern won't match.
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What are you wanting to straighten? Do you want to straighten the long edge of the board? Do you want to remove the bow from the board? Do you want to preserve the length of the board?
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If it is just bowed (not cupped) your best bet might be steaming it.

Sometimes, steam bending is the only real option to take out the twist in a board.

There is doing it with a steam box and doing it with a hot pipe.
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Cup = bend in the board across the width
Bow = bend along the length

By "cupped" I assume you mean convex side of a bowed board. I don't think it matters which side you straighten first, you're going to cut the other side parallel , right?

There are all sorts of jigs, I suppose if you did this a lot they would be worth the effort.

But the best way IMO is to fasten a straight edge to the board which will ride along the fence. It can be nailed or screwed to the waste side, so I usually attach it to the concave side and screw at the ends.

Be aware in a day or two some of the bow will likely return, so you may need to repeat the process. IOW do NOT rip it to size right way!!

A track saw is a very excellent way to straight line rip, too.
I don't see where the OP mentions the final dimensions he's shooting for.  3/4" doesn't leave a lot of material in many cases to be removed and still have a useful piece, depending on the amount of cup and warp present in the board.  They could be cut a little oversize in length and split down the middle, once done it could be jointed on the concave side and glued back together and eventually planed flat but you're going to lose thickness.
Something some have had luck with is leaving the boards on the lawn and letting the dew soak in and then let the sun hit it.  I've heard of some that this had worked to some degree.
I've never tried steaming a piece of wood that long, and if it's not air dried wood, not sure if steaming will work or not as the wood would have already taken a set due to the steam in the kiln.
Personally, I've not had the best of luck straightening wild boards like that except for jointing and planing shorter lengths and widths.  You will loose thickness and some boards are going to eventually cup and twist no matter what you do to try and straighten them out.  
You can try flattening the wood, but I wouldn't work it for a month or more after initial machining to see if the warp or twist comes back or not.  If it does, then I'm consider getting some different wood and use that wood for small projects.
My 2 cents.
Wow. From his question I’m assuming he has a crook, or what I call a cast and doesn’t know which side to present to the TS fence.
Hahaha. 4, 5 days and half a dozen replies later, we still have no clues what the op wants to resolve. Everybody (including the op?) seems to shooting in the dark. I've seen posts like this all the time in forums (mostly due to the ambiguous questions or non-responses from the ops).

Clarity would certainly help:

[Image: Wood_warping.png]

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