Safe ?

[randy lovelace]

Is it safe to make a cross cut on 30"x 11" 3/4 ply wood using a cross cut sled and using the fense as a stop? This is a Uni saw with a Uni fense. I know I can use a block on the fense but would rather not. I will have about 18" of fense on the sled on the right hand side of the blade. Thanks in advance for any replies. Randy south east ky.

[Matt Day]

If everything is calibrated and dialed in right, I think it would be okay. But I'd use a stop block with the sled. Or possibly just run the 11" side on the fence and be very focused on constant pressure against the fence so the piece didn't rotate (knowing my saw is calibrated and lubricated so there is very little sliding friction, etc).

[Dave Zellers]

Matt is right. If the sled is accurate then there is no need for the fence.
Using the fence as a stop for repeated cuts is a different thing and would require a block.

Using a sled and a fence for a cut means you are trying to adhere to two different reference points during a cut. Not good.

[Doug Garson]

Why do you feel you need a stop on a cross cut using a sled? I would only use a stop if I was making multiple cuts. I would clamp the piece to the sled if I was concerned that it might shift on the sled. You gave the dimensions of the piece you are cutting, what's the dimension of final piece?

[Brian Henderson]

That would be a perfectly safe cut, so long as you use some method of holding the workpiece down against the sled. I don't know if the worry is that it will lift in some way, but there are plenty of ways of just using a clamp to keep it in place and so long as the sled is square to the blade, there isn't much that can go wrong.

[Wade Lippman]

Done perfectly it is safe, as are so many other things.
Done slightly wrong, it will blow up in your face.

Plenty ways to do this; choose a safer one.

[Lee Schierer]

Is it safe? No! Trapping a piece between the fence and the blade when doing a cross cut is dangerous even with a crosscut sled. Put a desired cut mark on the leading edge of the piece being cut. Line that mark with the kerf in your sled or the blade teeth with the saw turned off. Hold the piece in place, turn on the saw and make the cut. No fence is required.

[Joe Spear]

If you have a Unifence, you should be able to slide the fence face back toward you so that the far end of the fence stops before the front edge of the saw blade. That way you can use the fence as a stop for the wood before it gets to the blade but will not trap the wood between the blade and the fence.

[Art Mann]

I agree with Wade and Lee. You need to either set your fence like Joe suggests or clamp a spacer block to the fence so the plywood is not touching the fence as it goes past the blade. Otherwise, you are asking for a kickback.

[Rich Engelhardt]

IYHATSWWBHTD...

(If you had a track saw, we wouldn't be having this discussion.)
I've decided to answer these types of questions with the above so I can easily search for them in the future when people say a track saw is good for only breaking down sheet goods.
Should you run out and buy one to make this one cut? Probably not.
But, if you add up all the odd ball things you run into then maybe one is a good idea.

[Gary Yoder]

+1 +1 +1 +1

If you have a Unifence, you should be able to slide the fence face back toward you so that the far end of the fence stops before the front edge of the saw blade. That way you can use the fence as a stop for the wood before it gets to the blade but will not trap the wood between the blade and the fence.

[Ole Anderson]

Hey Randy, Welcome to the Creek!

[Prashun Patel]

It's a trapping cut. If the fence of your sled does not extend all the way to the rip fence, then your off cut may twist after the cut. It's not safe.

I am unclear why you don't want to use a block on the fence? As long as that block ends before the first tooth of the blade, you should be ok.

[mreza Salav]

Not enough information (if the sled is on the left, or right, or both sides of blade, if there are hold downs on the sled to hold the piece, if there is fence behind the off-cut piece, etc).
In general if there is loose piece between the blade and the fence (e.g. your sled is to the left of the blade mostly and your off-cut is between the blade and fence) there is danger of kick back and so it is not safe.

[Matt Day]

I've done the trapping cut before, just making very sure pressure is kept against the table saw fence, like a normal rip cut. If you only hold the portion of the wood to the left of the blade you're asking for big trouble.

I think the block is to make it a non-trapping cut and to have something to register the board to.