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I just came across a table saw technique that I was unaware of.......use of a Half Fence. An article I saw said that Half Fences are a common feature on European table saws. To simulate the Half Fence on a Full Fence table saw a flat board is clamped to the rip fence...the board extends from the front end of the rip fence to the midpoint of the saw blade. Anybody tried it?
 

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I think a half fence for cross cuts is a good idea (think Delta's UniFence that has the ability to slide backwards), but a half fence for ripping? What happens when your wood gets past the half way point and suddenly dives to the right because there's nothing to support it? There's a possibility that your piece would then ride up on the blade. You want a solid fence to support your piece all the way through a rip cut.
That's my opinion only - others may chime in and tell me I'm all washed up.
 

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For ripping? Sounds like a bad idea to me. Certainly for cross cuts where you don't want a small cutoff piece trapped against the fence. But you only need a piece for what is really serving as a stop block. Rockler sells a nifty little clamp to hold the block against the fence.
 

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All of of the European Table Saws that I have seen in Germany were sliding to meet some requirement. They had a Festool sliding table saw. 12 years since I have been there.
Steve.
 

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I think a half fence for cross cuts is a good idea (think Delta's UniFence that has the ability to slide backwards), but a half fence for ripping? What happens when your wood gets past the half way point and suddenly dives to the right because there's nothing to support it? There's a possibility that your piece would then ride up on the blade. You want a solid fence to support your piece all the way through a rip cut.
That's my opinion only - others may chime in and tell me I'm all washed up.

Yes you are washed up! By the time the wood meets the blade the fence has done it's job. Past the midpoint of the blade it only serves to create a trap to push reaction wood against the back of the blade so that it may be shot back toward the operator.
Rob
 

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Hi, Im in the uk and anything but expert, but I cannot say Ive ever seen the type of fence you describe, lots of the small "contractor" saws seem to have quite a short fence but I think they still extend well beyond the blade, and Ive tended to think that this was to create a simple fence that was just clamped at one end, and which Ive heard people complaining about as being a bit too flexible.
Ive been thinking about fences lately because I have an extreamly basic home made sawbench, the fence being just a piece of very shallow steel channel, its 2" wide x perhaps 3/8" high, now there have been times when I would have liked a bit more height but more often than not I actually
like being able to guide the wood along the fence and whilst I have to be very carefull, its been enough to stop me making anything taller, I suppose its what you get used to.
Btw my fence is "loose" at both ends, a clamp at one end and a wing nut at the other, and I sight it useing lines scribed into the MDF top,,but I have to say I would not attempt the sort of projects you chaps take on.
Steve.
 

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Not sure a half fence would work well with grr-rippers


In woodworking there is always more then one way to accomplish something.
 

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Really hard to cut dados or any cut that does not go all the way through the board.
 

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Jim; I'm on your team! In spite of what Rob says, If I'm running a large panel through the saw I want it supported ALL THE WAY THROUGH ITS LENGTH!
To say that a 4x8 sheet won't move left to right, just because a 10" section is interacting with the blade is a fantasy.
 

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I think the difference may be that when using the short fence a splitter behind the saw takes over and guides the board the rest of the way through. This would keep a curved board from getting bound between the saw and the fence. Without that properly fitted and lined up splitter I wouldn't attempt it. In fact, I drilled my Unifence so that I could add a straight edge to extend it for some cuts.
 

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I think the difference may be that when using the short fence a splitter behind the saw takes over and guides the board the rest of the way through. This would keep a curved board from getting bound between the saw and the fence. Without that properly fitted and lined up splitter I wouldn't attempt it. In fact, I drilled my Unifence so that I could add a straight edge to extend it for some cuts.
The riving knife or splitter both protect the back of the blade from being touched but that is nothing to do with the short fence. The wood should never touch them unless it is reaction wood. Does your Uni fence not have enough length to guide to the back of the table if desired?
As for cutting sheet goods, the last section of a full length fence is only guiding the wood IF the wood is not being held firmly against the first section. Small table saws are not a great way to reduce full size sheet goods, they are why we have track saws, sliders and vertical panel saws. If you must use an ordinary table saw you can build it into bigger island like hardware stores did up till the eighties.
Rob
 

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Rob; or just use a normal fence.
I understand your argument, and I'm not saying that it doesn't have any merit. I AM saying that I'm very happy with my long fence (kicked a few thou out from the blade at the back) and i'm not planning on changing any time soon. I have neither the space nor the spare cash to plow into a $5K TS.
 

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The riving knife or splitter both protect the back of the blade from being touched but that is nothing to do with the short fence. The wood should never touch them unless it is reaction wood. Does your Uni fence not have enough length to guide to the back of the table if desired?
As for cutting sheet goods, the last section of a full length fence is only guiding the wood IF the wood is not being held firmly against the first section. Small table saws are not a great way to reduce full size sheet goods, they are why we have track saws, sliders and vertical panel saws. If you must use an ordinary table saw you can build it into bigger island like hardware stores did up till the eighties.
Rob
The Unifence is about 36" long I'd say without going to measure it. I can cut a full sheet of panel with it pretty accurately (it took a few tries to master the technique) but sometimes I need one a little longer. Trying to straighten out a warped board for example.
 

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Jim; I'm on your team! In spite of what Rob says, If I'm running a large panel through the saw I want it supported ALL THE WAY THROUGH ITS LENGTH!
To say that a 4x8 sheet won't move left to right, just because a 10" section is interacting with the blade is a fantasy.
Dan: You said you are on "Jim's" team and want a large panel supported all the way through, but Jim, the OP was wondering about using a short fence. I responded by saying I want the wood supported all the way through as well. I'm hoping you got the name's mixed up.

Rob: I don't argue with your opinion, so telling me that I'm "washed up" is a little over the top. MY OPINION, is that I wouldn't rip with a short fence. I referred to Delta's UniFence. In their instructions, all reference to ripping operations show the fence in it's normal position, front to back. In their reference to crosscutting, or in their words "USING THE FENCE AS A CUT-OFF GAUGE", they warn that the "rear end of the fence be positioned in front of the blade".

In my opinion, having no fence to support the work piece past the blade COULD create a pivot point as you push the work piece. What would prevent the would from pivoting into the blade? Why don't you just rip without a fence, maybe hurt yourself, launch a lawsuit and a new line of, say SawStops???

The link to the article tells us that the British think we (North Americans) are crazy. Yet these are the same folks that don't create saws with arbors that are long enough to support dado blades.

I'll keep using my fence in it's full position to rip boards and my miter gauge or panel sled to cosscut, thanks. Yup, I've still got all my fingers and plan to keep it that way.
 

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Some of my saws have full length fences but they usually have a false fence bolted to them allowing the blade to cut into them for some cuts,. It is dead simple to clamp a board to the first half of the fence giving you a short fence for free! Give it a try and you will prove my point. If you are relying on the fence past the blade to guide the wood, you have a serious technique problem! The old Jet-Lock style fence relied on the back rail to lock the fence in position. With modern T-Square designs the rear rail is no longer required. There is something to be said for not providing room for a heavy unbalanced object to be mounted on a saw arbour.
Rob
 

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Some of my saws have full length fences but they usually have a false fence bolted to them allowing the blade to cut into them for some cuts,. It is dead simple to clamp a board to the first half of the fence giving you a short fence for free! Give it a try and you will prove my point. If you are relying on the fence past the blade to guide the wood, you have a serious technique problem! The old Jet-Lock style fence relied on the back rail to lock the fence in position. With modern T-Square designs the rear rail is no longer required. There is something to be said for not providing room for a heavy unbalanced object to be mounted on a saw arbour.
Rob
Been doing it the old way for a couple of decades + without issues Rob. I'm pretty sure my technique is working. There may be other ways but there is nothing wrong with mine. And my dado doesn't vibrate. If yours does get a better one. I have an unused CMT I can ship you for less than retail. I got a good deal on it.
 
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Been doing it the old way for a couple of decades + without issues Rob. I'm pretty sure my technique is working. There may be other ways but there is nothing wrong with mine. And my dado doesn't vibrate. If yours does get a better one. I have an unused CMT I can ship you for less than retail. I got a good deal on it.
By definition your technique is wrong because you are not holding the wood tight against the first part of the fence therefore you do not have proper control of the work piece. It may well bite you one day. Try adding a quarter inch shim on the front half of the fence and practice a bit using scrap stock or styrofoam, you will be impressed. Realise that you should never put a non-straight edged piece of wood along a fence, tack it to a straight board instead.
I rarely use a dadoe but I do own a few mostly for use on a radial arm saw. They mostly use 2 tip cutters that can never be balanced but they do not vibrate. I prefer 1'' and 1.25'' shaft radial arm saws, my biggest dadoe is 12'' to use on the 18'' saws.
Rob
 

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Just looked this up and here in the UK the official safety advice published by the Health and Safety Executive says that the fence should extend no further than the front edge of the blade, and a riving knife should be fitted. I assume from this that the short fence and riving knife have to be used together, not either/or, otherwise it could be even more dangerous, not safer!

I suspect this advice is based on workshop accident statistics, and aims to protect the least experienced operators using a badly set-up machine.

My saw was made for the UK market and has a full length fence (with rear clamping bar) and an a bolt-on short fence. I have to agree that there's nothing except the riving knife to control the workpiece once the back end reaches the blade and I usually get blade marks on the last couple of inches of it as you can't stop it pivoting slightly, especially when using a push-stick.
 
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