What is the difference between a rip-cut and a cross-cut?

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In this answer talks about rip and crosscuts and that one saw is better for ripping than one that is more suited for crosscutting.

What is the difference between the 2 cuts and why would a saw-blade be more suited for one or the other?

ratchet freak

Posted 2015-03-20T23:53:14.513

Reputation: 3 324

Answers

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With the rip cut, you cut along the grain; while with the cross cut, you cut across the grain.

Cutting along the grain is a very easy cut; even before you had mechanical saw, you had saws with few but large teeth so you cut as fast and as straight as possible. Essentially, you "rip" the wood apart, like you can split it with an axe, except you'll get a straighter cut as you may still cut some of the wood fibers. This cut has a tendency to bind the blade as the wood fiber relax.

Cutting across the grain is much harder for the saw (you need to cut a lot of fibers), and you typically use a saw with smaller teeth, but many more of them.

One other reason why you have more or fewer teeth has to do with the amount of saw dust you need to evacuate after each cut. As the rip is easier, you'll need more space between the teeth to carry it out.

http://www.rockler.com/how-to/blades-101/ Image comes from http://www.rockler.com/how-to/blades-101/

Pascal Belloncle

Posted 2015-03-20T23:53:14.513

Reputation: 668

"Smaller gullets prevent too-fast feed rate" --oh, if only that were the case. In reality most people just push harder and end up with a wavy cut and scorch marks, then they blame it on a crappy blade instead of realizing they were using the wrong blade for the job! – rob – 2015-04-20T23:17:28.987

1What about cuts at angles? (Say 45 degrees) Do you use a rip, a crosscut or an hybrid blade? – Maxime Morin – 2015-03-22T13:14:41.110

1As @Damon shows in his pictures, any type of blade will make the cut, but some more poorly than others, or slower than others. When in doubt, I'd use the crosscut type blade, it might just take longer (if using a manual saw). – Pascal Belloncle – 2015-03-22T22:53:28.767

2@MaximeMorin: You can (and typically would) use a crosscut blade for 45° cuts, since it gives a much better miter. – Damon – 2015-03-27T19:18:34.600

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Pascal Belloncle has already given a good explanation of why there are two different kinds of blades, but what is the practical aspect of it?

An image speaks more than a thousand words:

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All cuts are done on the same piece of wood with a ryoba saw (one side rip, one side cross).

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You can immediately see that the rip cut with the rip blade goes twice as deep (both cuts were done pulling the blade along its full length 3 times). Also, you can immediately see that the cross cut with the cross blade comes out nicely whereas the cross cut with the rip blade is... well, far from perfect.

Damon

Posted 2015-03-20T23:53:14.513

Reputation: 2 909

didn't think of the japanese saws when answering, but this looks very illustrative! – Pascal Belloncle – 2015-03-22T22:51:25.857

@PascalBelloncle: The direct 1:1 comparison came out much better than I had even hoped. In the left cross-cut picture which was done with a rip blade, you can see how the rip blade literally rips the grain apart. One can probably hide this by carefully sanding the surface if it's visible, or you can just pretend it didn't happen if the surface disappears inside a hidden joint, but factually the grain/fibers that make up the wood have been torn apart brutally, and the wood's internal structure is broken. In comparison note how cleanly the grain is cut in the cross-blade cross-cut. – Damon – 2015-03-23T14:47:45.747

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Thinking back to something Roy Underhill said on The Woodwright Shop, probably 30 years ago, I thought that the teeth of a crosscut blade were angled perpendicular to the stroke of the saw, so as to work like a knife blade slicing through the wood fibers. The rip blade teeth pointed straight down, so as to work like a wood chisel splitting the wood fibers apart. Granted he was talking about hand saws, not power saws. Amazing that I still remember that after all this time.

Steve Connell

Posted 2015-03-20T23:53:14.513

Reputation: 11

2This post would probably be better suited as a comment. Part of my thought process when determining whether to put my response as an answer or comment is whether what I'm saying is a direct, concise answer or if it is more a point of discussion (and too much of that is also best taken to the appropriate discussion forum/thread etc.) I encourage you to review the tour again and read some more about Q&A on this particular SE. Good luck – Otto – 2017-12-08T15:55:26.937

1People can't comment until they have 50 reputation, which is probably why Steve chose to put this as an answer. Still, I agree it is more appropriate as a comment. I encourage Steve to ask a question or leave an answer on a recent question -- I think he'll find it isn't hard to hit 50 rep on this site! – Charlie Kilian – 2017-12-08T16:31:57.753

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The answer is in the name Cross Cut- Cut aCross the grain Rip Cut- cutting along the grain where the wood fibers can Rip out in long strands.

user1505

Posted 2015-03-20T23:53:14.513

Reputation: 1

3Can you backup the "long strands" claim? – Ast Pace – 2015-12-09T23:25:57.627

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To precisely answer the question: A rip cut is a cut along the longest dimension of the board or sheet. A crosscut is a cut along the shorter dimension of the board or sheet.

An example of a rip cut would be cutting a 4 foot by 8 foot sheet of plywood into a 3 foot by 8 foot sheet. In that case you would be ripping 1 foot off the sheet.

An example of a crosscut would be cutting a 1 inch by 6 inch by 6 foot long board down to 4 feet in length.

The differences in blades used for these types of cuts are described by Pascal's answer.

cathode

Posted 2015-03-20T23:53:14.513

Reputation: 593

8I like the grain explanation better. I get that the longest side if often in the grain direction. – ratchet freak – 2015-03-21T23:38:05.520

7But... it doesn't have anything to do with the longest or shortest dimension. All that matters is the direction of the grain. It is admittedly unusual to have the grain in the direction of the shorter dimension, but that's nevertheless totally possible. – Damon – 2015-03-22T17:10:31.120

I guess it depends on what you're doing: choosing a blade, or completing a cut. If you ask someone to "rip this board in half" and for whatever reason the grain is running along the short dimension of the board, you probably would still expect them to make a cut down the long dimension of the board. – cathode – 2015-03-22T17:28:04.087

4Rip vs. cross cut is in reference to the grain, the grain is 'usually' the long direction of a piece. that is why it tends to be a synonym for 'cut this the long way'. However, that is usage, not actually correct. if the grain was the short way but you wanted to split it the long way, you would still need to use a cross cut blade for best results, not a ripping saw. – bowlturner – 2015-03-23T13:03:07.747