Cross Cut vs Rip Cut

dusty · Post by **dusty** » Fri Mar 16, 2012 8:29 am

Is direction of the grain the only distinguishing difference between a cross cut and a rip cut?

Asked another way: If I am cutting a piece of MDF across the short dimension - would this technically be considered a 'cross cut' AND therefore I should not be using the rip fence?

robinson46176 · Post by **robinson46176** » Fri Mar 16, 2012 8:33 am

dusty wrote:Is direction of the grain the only distinguishing difference between a cross cut and a rip cut?

Asked another way: If I am cutting a piece of MDF across the short dimension - would this technically be considered a 'cross cut' AND therefore I should not be using the rip fence?

That would be my thinking...

Expanding that a bit, as long as the material was narrow one way like a board. If it were more nearly square like a rectangle such thinking would not be automatic...

.

dusty · Post by **dusty** » Fri Mar 16, 2012 8:52 am

I was asked to cut up a bunch of MDF into door panels. The finished size is something like 11"x15".

After getting to an 11" width, I have been cutting them to length using the rip fence. While doing so, I just got to thinking that I might be asking for trouble.

Thinking about it now is rather stupid because I have already cut the thirty pieces. I just thought that some conversation might prevent someone else from doing this if it is inappropriate.

robinson46176 · Post by **robinson46176** » Fri Mar 16, 2012 9:15 am

dusty wrote:I was asked to cut up a bunch of MDF into door panels. The finished size is something like 11"x15".

After getting to an 11" width, I have been cutting them to length using the rip fence. While doing so, I just got to thinking that I might be asking for trouble.

Thinking about it now is rather stupid because I have already cut the thirty pieces. I just thought that some conversation might prevent someone else from doing this if it is inappropriate.

Others might disagree but personally would consider that kind of L / W ratio totally appropriate for what you are doing.

I really believe that one thing that I see done (just this week on TV in fact) that is "asking for it" is a cut where the material is being pushed with a hand on each side of the blade.
Unlike a sled where the push is always uniformly straight ahead, pushing with a hand on each side of the blade can quickly pinch the blade at the end of the cut. I see TV guys "resting" their left hand on the material left of the blade while pushing with the right hand. A "resting" hand can easily become a pushing hand without the intent to.
That and I am amazed at how many times I see a cut on TV where the material is lifting up from the table surface by as much as 1/2". The operator may not see it but the second camera does...

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dusty · Post by **dusty** » Fri Mar 16, 2012 9:59 am

robinson46176 wrote:Others might disagree but personally would consider that kind of L / W ratio totally appropriate for what you are doing.

I really believe that one thing that I see done (just this week on TV in fact) that is "asking for it" is a cut where the material is being pushed with a hand on each side of the blade.
Unlike a sled where the push is always uniformly straight ahead, pushing with a hand on each side of the blade can quickly pinch the blade at the end of the cut. I see TV guys "resting" their left hand on the material left of the blade while pushing with the right hand. A "resting" hand can easily become a pushing hand without the intent to.
That and I am amazed at how many times I see a cut on TV where the material is lifting up from the table surface by as much as 1/2". The operator may not see it but the second camera does...

.

The DIY shows often scare the bejibbers out of me. I am amazed that the producers show some of the hazardous things they do.

Gene Howe · Post by **Gene Howe** » Fri Mar 16, 2012 10:04 am

Dusty,
With MDF, or other amorphous materials of that dimension, there wouldn't be any safety concerns.
Be the same thing as ripping a 15X15 or 11X11 piece.
I square up MDF pieces of that size, or a bit smaller, in rip mode.
I would think their might be a problem when the length/width ratio is a lot more, though.

dusty · Post by **dusty** » Fri Mar 16, 2012 10:47 am

Gene Howe wrote:Dusty,
With MDF, or other amorphous materials of that dimension, there wouldn't be any safety concerns.
Be the same thing as ripping a 15X15 or 11X11 piece.
I square up MDF pieces of that size, or a bit smaller, in rip mode.
I would think their might be a problem when the length/width ratio is a lot more, though.

Initially, these pieces were 8' long. I got down to manageable lengths, using the cross cut sled, before I did what is being discussed here.

pennview · Post by **pennview** » Fri Mar 16, 2012 11:28 am

If you do some searching regarding safe practices on ripping stock, you'll likely come across a so-called rule that you shouldn't rip anything less than 12". And, I'd expect that's a good rule for someone with little or no experience with a saw. The thinking being that it's hard to control short pieces of stock against the fence.

The other point about ripping the shorter side of a panel, it shouldn't make much difference given the sizes you're dealing with, but it would be easier (and therefore safer) to rip with the longer end against the fence. It's simply a bit easier to control the stock. The problem has to do with cocking the stock between the fence and blade, which if that happens could be a bit unnerving to say the least.

I'd think that making those panels would be a perfect job for the cross-cut sled. But there are lots of ways to do things.

dusty · Post by **dusty** » Fri Mar 16, 2012 12:56 pm

pennview wrote:If you do some searching regarding safe practices on ripping stock, you'll likely come across a so-called rule that you shouldn't rip anything less than 12". And, I'd expect that's a good rule for someone with little or no experience with a saw. The thinking being that it's hard to control short pieces of stock against the fence.

The other point about ripping the shorter side of a panel, it shouldn't make much difference given the sizes you're dealing with, but it would be easier (and therefore safer) to rip with the longer end against the fence. It's simply a bit easier to control the stock. The problem has to do with cocking the stock between the fence and blade, which if that happens could be a bit unnerving to say the least.

I'd think that making those panels would be a perfect job for the cross-cut sled. But there are lots of ways to do things.

There is no doubt that the cross cut sled would have been the safest way and probably every bit as accurate.

Gene Howe · Post by **Gene Howe** » Fri Mar 16, 2012 3:06 pm

When it looks scary to me, and I have multiple identical length pieces to cut, I just clamp 3/4X 2X piece at the infeed end of the fence. Then use a scrap piece of 3/4 at the the blade to measure the length of the cut. Then I use the miter gauge for the cut, sliding the work to the piece at the end of the fence for correct length.
A sled and stop block would be just as easy, though.
But generally, anything over 8" wide and 12" or less long, I just use the fence.