What is meant by a rip-cut and a cross-cut (esp. on a table-saw)

[Steve]

I am looking at a new table saw purchase, and have been reading many of the past posts in this newsgroup. I am trying to determine what the essential differences are that define a rip cut vs. a cross cut, particularly as done on a table saw and from a safety standpoint.

One particular question that comes to mind, is the following. When I think of a cross-cut (on a table saw) I think of any cut where the width of the board (dimension left-to-right on the saw top) is greater than the depth of the board (depth front to back) - i.e if one were taking a 1' x 3' panel and cutting it down to 1' x 2.5'. This would seem to be a cross-cut. Am I correct in understanding that this would be best done using a sled or a mitre guage?

If so, then the primary use for a 52" rip fence (as opposed to a 30" fence) would be to rip plywood, for example from 4' x 8' to 3.5' x 8' (in the case of doing cabinetry work)? And the rip fence is not intended as the reference to be used for example, to take a 1' x 6' board and cut it down to 1' x 4' by setting the fence to 48".

Thanks in advance.

[Bay Area Dave]

Steve,

You've got it figured out!

Sleds or miter gauge for cross cutting and the fence for rips of sheet goods or lumber. My sled is about 17" deep so I can cross cut sheet goods once they've been ripped down to

[mel]

Rip cut and cross cut refer to the orientation of the grain of the wood you are cutting regardless of the dimension of the board.

[Bay Area Dave]

what do you call a "long" cut on a 1' x 6' piece of melamine or ply, then?

dave

mel wrote:

[Andy Dingley]

There's only one difference - anything else is a confusion.

Ripping goes along the grain, crosscutting goes across it. As timber is fibrous, this is quite a different cutting situation. A rip saw acts like a row of chisels, a cross cut saw like two rows of knives. If you're using a handsaw, you need to sharpen it correctly, or you're in for a workout. If you're using a powered saw, particularly with carbide insert teeth, then you just throw more power at it. Very few powered saws have what we'd normally think of as knidfe-edged "crosscut" teeth, because they'd be too weak for a brittle material like carbide to be driven at powered speeds.

If you rip a long board, then (depending on the timber and its seasoning) the cut may either splay apart, or it may close up. Closing up and grabbing at the blade is dangerous, so we use splitters or riving knives to reduce the hazard.

As to the fence / sled / mitre gauge issue, then this is one entirely of proportion and not orientation. But trees are long and thin, so we tend to confuse the two - although rarely in a way that's ambiguous.

If you're cross-cutting narrow slices from a wide board (maybe you're making Tunbridge-ware banding) then use the fence - provided the board is short enough for you to still control it.

-- Smert' spamionam

[David Babcock]

The terms are related to the grain of the wood, although sometimes such as with plywood, or other laminated materials the term rip tends to get used more. But anyway rip denotes cutting with the grain (the blade fairly rips through the wood), and crosscut is across the grain, (pretty self explanatory)

Dave

[Doug Winterburn]

...and don't forget resawing - a thickness reducing rip rather than a width reducing rip. Also bevel cuts, miter cuts and compound miter cuts, mostly forms of crosscutting.

-Doug

[Luigi Zanasi]

On Fri, 19 Dec 2003 18:20:16 GMT, "mel" scribbled

Yup. The real issue from a safety perspective is whether your cut is considerably longer than the diameter of your blade. If it is, it's relatively safe vis à vis kickback and you can use the rip fence, no matter the grain orientation. Doesn't matter whether you're ripping or cross-cutting. My only major kickback happened when I was ripping a

5-inch long piece of 2X4 (yeah, I know, stupid). On a large piece of plywood, say 16" or wider, I use the fence rather than a sled. So, the 52" table is useful for "cross-cutting" full length sheets of plywood.

Luigi Replace "no" with "yk" for real email address

[Phil Crow]

Well, Steve, does that about cover it?

[mel]

I know what you are saying but the terminology was used long before melamine laminated sheet goods existed. Plywood has grain orientation does it not? If you were going to cut a piece of plywood that was 1'x4' with the grain running side to side the narrow way which blade would you use, a rip blade or cross cut blade? That being said, let's agree you can cross cut with the rip fence when the size and grain warrants and vice versa. Deal?

[mel]

ok.. before I get flamed that was a poor example.... I wouldn't use a rip blade on ply in either case.

[Bay Area Dave]

you example is so lame as to defy a reply. Please try again!

dave

mel wrote:

[kb8qlr]

Try a SHARP plywood blade.

[mel]

geeesh.

[nospam]

melamine panels have no long wood fibers in them. it matters not a bit which direction you cut- all directions are exactly the same. to get a really good clean chip free cut on the top and bottom faces pretty much requires a quality saw well tuned up with a specialty blade on it. that stuff just wants to chip.

the individual plies have a grain direction, but the plies alternate direction. for all practical purposes all cuts in plywood can be considered crosscuts (use a crosscut blade).

always a crosscut blade for plywood....

Bridger