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.

[Art Mann]

I have found that it is often more important that a set of pieces be cut to the the same length than that they be exactly the right length. If you are using a track saw, you are having to measure and mark each piece square and then position the saw guide so it cuts in the right place. That is two big opportunities for error. I have been woodworking for 40 years and I have not yet developed the skill to mark and cut a series of pieces so that the length is close enough that you can't feel the difference stacked together. Both of these error sources are eliminated by using a table saw and sled with a stop block, either sled or fence mounted. I have a track saw and use it all the time where it is appropriate. I just said all this to emphasize that a track saw is not an adequate substitute for a table saw in every case.

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.

[Larry Browning]

You have described the classic miter/fence no no. DO NOT DO THIS! I am a bit confused as to why you think you need to use the entire length of the fence as a guide. Why not just clamp a small scrap to the front part of the fence to use as a stop block, then push the board past the block before the board contacts the blade? This is pretty standard practice.

[Matt Day]

Larry, I think that's the block he's talking about.

[glenn bradley]

First off, we On my way! You can see me using a stop block on my fence in this picture:

[Brian Henderson]

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.

Maybe I read what he was doing wrong, but I didn't see him using the tablesaw fence, I saw him using the fence on his sled. One is safe, one is not.

[Marty Tippin]

I guess I've been doing it wrong.

Just this weekend, I needed to cut several pieces of plywood to the same length - longer than the rear fence on my cross-cut sled, regardless of which side of the blade I was on. But not farther than the table saw fence on the right side of the blade. So I just locked the fence at the width I wanted to cut, put the pieces on the cross-cut sled and held them down and firmly back against the cross-cut sled's fence and away I went. Cut 6 or 8 pieces, all identical length, zero time spent measuring and nothing moved during or after the cut (just like always on the cross-cut sled).

I honestly don't see where the danger was. Sure, if I had a lot of stock hanging past the end of the sled and against the fence *and* I wasn't holding it in place against the back rail of the sled, I suppose it could have twisted and caused a kickback. And yes, I could have added a small block to the side of the table saw fence and spent a minute with the measuring tape to get it all exactly where I want it. But with the fence properly aligned to the blade and the stock held firmly in place on the sled, I see zero danger.

[Larry Browning]

Larry, I think that's the block he's talking about.

I guess I am confused about what he is describing then. The way I read it, he wanted to use the fence without a block and a miter sled to do a cross cut operation. The entire fence was to be the "stop block" and the board would be against the fence throughout the entire cut. This is dangerous because even the slightest movement away from the fence or if the fence has a slight toe in it will cause the board to bind against the blade and fence resulting in a really bad kickback which will not only destroy the board but quite possibly cause major injury or death.

Maybe the better question is, why do you not want to use a stop block?

[Marty Tippin]

The way I read it, he wanted to use the fence without a block and a miter sled to do a cross cut operation.

The OP never mentioned a miter gauge; he said he's using a cross-cut sled. Presumably, he's talking about something that looks kind of like this

330248

[Jim Becker]

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.

This. The fence should always end just before the front of the blade for a cut like this. And the design of the UniFence specifically accommodates it! (same goes for the fences on most Euro saws)

[Sam Murdoch]

I guess I've been doing it wrong.

Just this weekend, I needed to cut several pieces of plywood to the same length - longer than the rear fence on my cross-cut sled, regardless of which side of the blade I was on. But not farther than the table saw fence on the right side of the blade. So I just locked the fence at the width I wanted to cut, put the pieces on the cross-cut sled and held them down and firmly back against the cross-cut sled's fence and away I went. Cut 6 or 8 pieces, all identical length, zero time spent measuring and nothing moved during or after the cut (just like always on the cross-cut sled).

I honestly don't see where the danger was. Sure, if I had a lot of stock hanging past the end of the sled and against the fence *and* I wasn't holding it in place against the back rail of the sled, I suppose it could have twisted and caused a kickback. And yes, I could have added a small block to the side of the table saw fence and spent a minute with the measuring tape to get it all exactly where I want it. But with the fence properly aligned to the blade and the stock held firmly in place on the sled, I see zero danger.

Well you had a perfect moment. Don't depend on that happening every time. Lots of good advice in the posts preceding yours from very experienced woodworkers that should give you pause to reconsider your technique. One bit of inattention or distraction, one chip of wood overlooked (at either fence) a bit of wobble in your sled and you will likely get cracked in the head (at the least). Just sayin'!

[Roger Feeley]

Brian, I'm not so sure. During the cut, I think everything would be fine. My worry is at the moment the cut is complete and the piece between blade and fence comes loose.

[Brian Henderson]

Brian, I'm not so sure. During the cut, I think everything would be fine. My worry is at the moment the cut is complete and the piece between blade and fence comes loose.

If you're holding it against the back of the cross-cut sled, it doesn't matter. It's not going anywhere.

[Rich Engelhardt]

I have found that it is often more important that a set of pieces be cut to the the same length than that they be exactly the right length. If you are using a track saw, you are having to measure and mark each piece square and then position the saw guide so it cuts in the right place.I didn't see any place where the OP mentioned he had more than one piece of plywood to cut.
Even if he had though, I've used my track saw to make multiple pieces the same dimension w/out any trouble at all.
It just takes a few extra seconds of setup.

[glenn bradley]

This is how tablesaws get a bad name ;-) ALL kickbacks are user caused; a properly functioning tablesaw does not kcikback . . . it needs our help. Folks who have experienced a kickback generally give them the respect they deserve. Something restricted to the miter slot (gauge, sled, Dubby, etc.) moving material past a blade that is restricted by the fence is a recipe for kickback. Is it guaranteed to happen? No. Will it happen? Yes. The fact that I may have gotten away with doing something unsafe for years only means that my turn is coming up sooner ;-) My stop block add exactly 3" to my measurements, easy peasy to factor that in and 3" is a lot of room for something to get wonky without being pressed against the blade. I've seen people do all sorts of things that I would never do. Some people don't wear seat belts, or signal, or wear helmets or hearing protection. We should all do what we want but, we shouldn't blame an "accident" on poor methods or shoddy equipment. -- cheery rant off -- ;-)

[Larry Browning]

The OP never mentioned a miter gauge;

Neither did I. But in reality, in this context a cross-cut sled functions just like a miter gauge. The only time it is safe to use a miter/fence combination is a non-through cut, like a dado or grove cut. Otherwise it is unsafe, period. Do so at your own risk, but don't say you have not been warned.

[Matt Day]

I like how a first poster shows up and asks an unclear question, then we go back and forth all day when we really need to OP to give us clarifications. Come on!

[randy lovelace]

First off let me thank everyone their replies. Mr. Day this is my first post. I have been clearing snow most of the day and many other things. This is the first chance I had time to sit down and reply. Please excuse me for being so rude. Joe spear you had a great idea that I would never have thought of, sliding the fence back. Rich I do have a track saw and use it very often. I buy my plywood sawed in 3 sections 31" ( I am old and lazy) and can haul it under my bed cover and keep it out of the weather. When in the shop I rip it into 11" wide pcs. And need to cut them to 30"

[randy lovelace]

Glenn, the idea of using a 3" block is good. If I don't slide my fense back this is what I will do. The only reason I didn't want to use a block ( I will admit was being lazy ) I guess it all falls back to my favorite saying, If it don't feel right don't do it.

[Matt Day]

Randy, I meant that jokingly for those of us who put some time into this thread without all the information needed. I'm sorry for being so rude.

Use a registration block. I have one within easy reach of the table saw using these clamps on them for easy attaching.
http://www.rockler.com/universal-fence-clamps?utm_source=google&utm_medium=cpc&utm_term=&utm_content=pla&utm_campaign=PL&sid=V9146&gclid=Cj0KEQiAz5y1BRDZ4Z_K_eGa84cBEiQAtQkeaPwicpn3 ZsKidUVh6vMu4cMlxYHAUYuYSLVTb7xBQH0aAgd58P8HAQ

[Jim Becker]

Glenn, the idea of using a 3" block is good. If I don't slide my fense back this is what I will do. The only reason I didn't want to use a block ( I will admit was being lazy ) I guess it all falls back to my favorite saying, If it don't feel right don't do it.

Randy, the primary reason to slide the fence back rather than using a block is because one of the benefits of the UniFence (and similar movable fences) is that they maintain distance accuracy with the "scale on the rail"...no mental math to calculate the thickness of the block vs what shows on the scale and the resultant increased risk of a "boo boo". It only takes a moment to unlock the fence to change its position. This is a benefit for "standard ripping", too, as you can end the fence just beyond the blade (with a splitter/riving knife) to release pressure and potential binding for "lively" material.