What am i Missing?? need advice on TS Ripping issue

[Mike Metz]

I'm looking for some input on a problem I'm having with my new tablesaw when ripping narrow stock (3" & less). my old tablesaw ripped without any issues. (both are Grizzly's)
When i start the rip cut, the full edge of the board is flush against the fence, but when i am in the middle or approx middle of the cut the front end of the board is pulling away from the fence resulting in the blade cutting to much into the board. (Say for example the cut i intend to make is a 2 1/2" wide board, on both ends the board is a correct 2 1/2" but in the middle its 2 7/16" or worse) i have tried to adjust my hands and the pressure I'm applying to the board to over come the issue without any luck. the only way i can overcome this issue is to feed it using one hand behind the blade and the other in front, i know its not safe and want to get away from this. I have checked for blade/fence parallelism and both are at .000 when using a dial indicator. I'm using high quality Freud full kerf blades and the riving knife is set even with blade...so I'm asking for the help of anyone that has some advise on this issue.

Thanks for any advise in advance

[johnny means]

i have a similar problem. In my case the issue is my fence face, the ends bow towards the blade. At the beginning and end of the cut my stock can ride against the portion of the fence next to the blade, but in the middle of the cut the stock rides the ends of the fence while straddling the portion of the fence next to the blade

[Peter Quinn]

My first check wold be the fence plate face. Is it flat and square to the table over it's entire length? Is there some sort of splitter or roving knife involved, and if so is it adjusted properly?

[Myk Rian]

Have you checked the alignment of blade to miter, and fence to miter/blade?

[Harvey Pascoe]

I've had the same problem and eventually traced it to the saw blade getting a build up of resin on the sides of the carbide tips. I washed with lacquer thinner and a brass brush to remove it and it stopped. I think what was happening was due to excessive friction pulling the workpiece away from the fence and into the blade the further the cut went along. Is that what is happening? If so, check and clean your blade.

[Peter Aeschliman]

I have had the same problem as well. Blade is clean and flat. Blade is perfectly aligned to the miter slot as is the fence. Splitter and riving knife are aligned as well.

I have found this to be a problem when I'm feeding the workpiece without a feather board. I've also noticed this problem when I haven't jointed the edge and the face to get flat surfaces at 90 degrees to one another.

Have you tried using a feather board just before the blade, and are you jointing your workpieces before going to the table saw?

[Mike Metz]

Thanks to everyone input so far... this problem is driving me crazy!.. here's what i have tired based on input above.
I Start the initial cuts with a jointed edge of the board, consecutive cuts after are not jointed as i am using a glue line rip blade, that normally cuts very well.
My Fence is true and flat using a lee valley straightedge.
I have not used a featherboard as of yet, but i was thinking of that method as well.
I have cleaned the pitch and resin off all my blades and same results.
The alignment of the miter slot/blade/fence is all at .000 difference.

I am going to check the arbor run out of the blade, (i checked on initial setup, but not since)

I also failed to mention earlier that when the blade is cutting further in the wood, it is also burning the wood in the middle of the board but both ends are clean and smooth.
Once again thanks for all your help, and look forward to more ideas

[Don Jarvie]

I found myself with the same problem and its all about how your feeding it. I broke down and bought the Gripper. I found the problem was not enough pressure down on the board to hold it against the fence. To prevent this the board needs to stay against the fence as it passes the blade. Its fine at the beginning since you can hold the board against the fence as its fed into the blade and its fine at the end because the push stick will keep enough pressure on the end to keep it against the fence. The Gripper will allow you to keep enough pressure over the middle of the board during the cut.

I also found this can happen on a long board when you remove your right hand and switch to a push stick. The transfer is just enough to kick the board slightly away from the fence.

Don

[Jeff Duncan]

Before going further toss a combo blade in there and see if you get the same problem cutting a piece of either plywood or mdf. If not you know it's not the fence or alignment.

good luck,
JeffD

[Myk Rian]

Is the wood thicker than 1"? The GLR blade is only good to that thickness.

[James Baker SD]

Any chance your splitter or riving knife is not centered with the blade? Seems if it were a little closer to the fence than the blade is, it might try to rotate the workpiece as you push the workpiece past the knife.

[Mike Metz]

I have only been using 4/4 stock since i noticed this problem. i just triple checked the fence, arbor, blade and miter slot... all have less than .001 variance. i will try the plywood and mdf idea next. i have a Freud primer blade to try, so i will try that. all my other blades are from my old saw and are thin kerf so they will not work the the splitter or riving knife.. although i guess i can try them to see if that is the cause.

[joe milana]

Try toeing your fence in a LITTLE. I know your measurements say everything is parallel, but possibly there is an error sneaking in somewhere. The wood really wants to follow the blade with those side grind blades; I've had it happen to me. Read and trust the wood before the micrometer. If you get consistent burning on the fence side of the kerf, toe the fence out a bit. Use something like maple or cherry that burns easily while testing and make sure it's dry and stress free.

[Bob Carreiro]

It could be your blade causing the drift. Once you ensure your fence is parallel to the blade/TS slots and your rip still walks away from the fence, either change your blade, or get used to it and compensate for it. You can compenste for this drift by setting up a feather board on the far side of the blade, or simply apply pressure with your fingers on the board, pressing it against the fence after it reaches the far side. It works.

[Bob Carreiro]

It could be your blade causing the drift. Once you ensure your fence is parallel to the blade/TS slots and your rip still walks away from the fence, either change your blade, or get used to it and compensate for it. You can compenste for this drift by setting up a feather board on the far side of the blade, or simply apply pressure with your fingers on the board, pressing it against the fence after it reaches the far side. It works.

[Joe Fabbri]

Hi guys,

I am constantly having the same problem, and while I figure it's due to the way I'm feeding it, perhaps it's also compounded by my saw blade.

It does seem to go away with a featherboard, set starting slightly before the blade and extending to the middle of the blade area. But if I don't use the featherboard, it starts drifting, unless I lean over and hold it steady from the side as it first passes the blade.

Now, I just have a cheap Ryobi portable saw that I use for general work. I've noticed about the Ryobi, that when you start it, the blade seems to jerk into position a bit. Maybe it's the junky nature of the saw, and blade doesn't stay steady. I don't seem to remember having as much trouble ripping on my older stationary Craftsman contractor saw. It's hard to find a good clamping surface on this Ryobi too, so attaching a featherboard for certain cuts in hard to do sometimes.

Do other people find their portable saws pushing the board away from the fence also? I find myself often allowing a 1/16 or so extra on cuts to accomodate for the saw slightly pushing the board away and cutting it narrower.

[Gregory King]

Raise the blade up to the highest point. Check both measurements from either end of the blade back to the miter slot. I 'd bet that is out slightly. I bought a King table saw here in Canada with the same problem. There are 4 bolts on my arbor base that allow for slight adjustments. Not sure how the Grizz is built since i have never owned one.

[michael veach]

Thanks to everyone input so far... this problem is driving me crazy!.. here's what i have tired based on input above.
I Start the initial cuts with a jointed edge of the board, consecutive cuts after are not jointed as i am using a glue line rip blade, that normally cuts very well.
My Fence is true and flat using a lee valley straightedge.
I have not used a featherboard as of yet, but i was thinking of that method as well.
I have cleaned the pitch and resin off all my blades and same results.
The alignment of the miter slot/blade/fence is all at .000 difference.

I am going to check the arbor run out of the blade, (i checked on initial setup, but not since)

I also failed to mention earlier that when the blade is cutting further in the wood, it is also burning the wood in the middle of the board but both ends are clean and smooth.
Once again thanks for all your help, and look forward to more ideas

It looks like you have done a good job of checking all of your alignments. With everything aligned, I have found two things that can cause this. The blade, wood movement during feeding. Besides the feather boards, if you are using out feed rollers, make sure they are aligned to the table and square to edge. If one end is closer than the other, it will cause the board to walk.

[David Cefai]

In my case the solution was (and still is) a featherboard. YMMV.

[Damon Stathatos]

... a featherboard, set starting slightly before the blade and extending to the middle of the blade area...

Doesn't that cause the off-cut to 'rock and roll' after the cut is complete? I've never tried it this way figuring that would be the case. I always end my featherboard just before the blade.

[Joe Fabbri]

I don't have an exact science yet to using the featherboard, because I'm still pretty new to all this. I can't recall how the off-cut piece reacts exactly, though I probably haven't experienced any real issue with it.

Rethinking what I do, though, I probably don't go as far in as I originally said. I probably put it less than half way into the blade, and two inches or so before the blade (the featherboard being a 1x6 board)). In general, with the issue of pulling away from the fence that I get past the blade, I try to make sure it's pressed as tight as possible as far along as possible. I don't really need too much pressure before I start the cut, unless I'm ripping something long and it's hard to get started tight to the fence.

Maybe it's not the right way to do it, I don't know. I try not to keep the featherboard too snug, though, in order to prevent any problems. But, I'm curious to hear what other says about the proper location of the featherboard, if there is one.

Joe

[ian maybury]

It's risky to lean over the blade, better to get stuck in and sort out whatever issue is preventing a more normal feeding procedure.

It'd make sense to try a different blade in case it's anything to do with one being a dud, and to make sure the riving knife etc is lined up with the blade and not too thick for it. It sounds though very much like the sort of thing likely to follow if the blade is toed out too much at the rear from the line of the fence - or that the fence is deflecting or is aligned away from the blade enough that it's producing a similar effect.

Check that the fence is strong enough that it isn't springing side to side under the pressure of holding the wood against it too, and that it's locked down. if the fence is flimsy it may be possible to get a clamp on to hold down the rear.

The burning may also suggest an blade/fence alignment issue - if the blade is offset enough relative to the line of travel of the wood as determined by the fence the sides of the teeth at the trailing edge may rub the cut.
standard to set the blade parallel to the mitre slot, and to then set the rip fence so that the rear of the blade is parallel or perhaps a thou or two further out than the front. Check for runout in the arbour and saw blade while you are there too.

There's lots of write ups about on how to align a saw. Here's a Wood Whisperer video that avoids the need for fancy dial gauges and the like: http://www.youtube.com/watch?v=lxRSarTJLMU&feature=relmfu

[Peter Aeschliman]

I don't have an exact science yet to using the featherboard, because I'm still pretty new to all this. I can't recall how the off-cut piece reacts exactly, though I probably haven't experienced any real issue with it.

Rethinking what I do, though, I probably don't go as far in as I originally said. I probably put it less than half way into the blade, and two inches or so before the blade (the featherboard being a 1x6 board)). In general, with the issue of pulling away from the fence that I get past the blade, I try to make sure it's pressed as tight as possible as far along as possible. I don't really need too much pressure before I start the cut, unless I'm ripping something long and it's hard to get started tight to the fence.

Maybe it's not the right way to do it, I don't know. I try not to keep the featherboard too snug, though, in order to prevent any problems. But, I'm curious to hear what other says about the proper location of the featherboard, if there is one.

Joe

Hi Joe,

You definitely don't want the feather board pushing the waste piece against the blade. Depending on the piece being cut, this could cause the waste piece to kick back at you. Do a search for my recent thread on kickback. I have a really bad scar on my forehead that proves the TS can throw wood at you with incredible force.

Plus, there's really no benefit to having the feather board positioned that way since the workpiece is on the other side of the blade.

[Steve Ryan]

Is the jointed edge of the board dead straight before the first rip? And is this same edge straight after ripping the stock? Does the kerf get wider than the blade when you are half way through the board? Clean cut at the start and end but burned in the middle indicate some stress being relieved when cutting. When I need dead straight rips I usually rip a bit wide and re joint and re rip to final dimension.

[Matt Kestenbaum]

Have you checked the arbor for run-out? If you have a dial indicator -- you used it to check for parallel right? -- then a magnetic base is all that you'll need in checking for run-out.

[Joe Fabbri]

Hi Peter,

Thanks for confirming this. Thinking about it when writing my response to Damon, it did seem problematic, because it would jamb up the blade. I don't recall having had many issues with it this way, so the only thing I can think of is that I keep the featherboard pretty loose and it doesn't become any issue. Or it's set even more before the blade than I can realize.


Regardless, now I'm going to pay more attention to this and keep it away from the blade area altogether.

Yes, I know how bad a kickback can be. The other day I was ripping an angle on a 2x6. It was a short piece, and I didn't have any outfeed on the table. Well, it tipped on me at the end, and at the end I couldn't push it through to finish the cut, and it shot back like a bullet. It cracked the end of my pushed stick. Luckily I have the habit of standing to one side of the saw, and not directly behind it. Since then, I've been wearing a full face shield that I use for grinding. I only occasionally used it in the past, but now I want to try to use it all the time.

Thanks guys,

Joe

[glenn bradley]

[QUOTE=Joe Fabbri;1758038a featherboard, set starting slightly before the blade and extending to the middle of the blade area[/QUOTE]

Anyone else have a near-heart attack when they read this?

The OP's problem prompted the usual reaction of questioning alignment; that was my initial suspicion. Since that seems not to be the problem, I would turn to technique. You should not have to muscle your material through the cut. If the face and fence-edge have been jointed flat and perpendicular, your material should move through the path without issue. If you have not face and edge jointed the material and are relying on "factory" edges things get unpredictable. You may be able to bend the material to your will via featherboards on the fence pushing down and on the table (ahead of the blade) pushing toward the fence but, I prefer properly prepared material. Also, frustration can lead to over-focusing on one part of your technique and sabotaging yourself as to overall result.

[Jim Heffner]

Peter, I have read the other posters replies to you problem, I think the problem may be a crappy blade on the saw. If it is an original blade that came with the saw....change it out for a better quality blade and the problem probably disappear. The blade that came with the saw is a basic blade not designed for quality cuts in my opinion and they aren't my choice to produce good clean cuts!

[Lee Schierer]

I have checked for blade/fence parallelism and both are at .000 when using a dial indicator.

Set the blade parallel to the miter slot and the fence parallel to the same mite slot if you haven't already done that.

Then I would get a set of Griptite magnetic feather boards (http://www.grip-tite.com/GT1/Home_files/2000.jpg) and mount them as shown in the photo205412. They offer a roller mounted on the side for ripping, get that roller. The one mounted sideways will continuously bias your board toward the fence and keep it there. I have a set and use them all the time. I rarely see a tooth mark on my rip cuts and it is hard to tell the ripped edge from the jointed edge using a Freud rip blade.

[Peter Aeschliman]

I definitely like the idea of having some kind of feather board behind the blade... problem with that setup is that you won't be able to use most blade guards with any kind of feather board or hold down when you're doing narrow rip cuts (as pictured). But for wider cuts, I imagine that works great.

[J.R. Rutter]

It is also quite common for moisture differential between center and outside surfaces of the board to cause this. The center is generally drier and the outer surfaces have tension as a result.

Did you try an MDF cut per JeffD's suggestion?

[Peter Aeschliman]

Here's another product that might help hold the piece against the fence after the blade... same problem though- it will interfere with your blade guard for narrow cuts.

http://www.woodcraft.com/Product/2003794/30976/Yellow-OneDirection-AntiKickback-Safety-Rollers.aspx