Table Saw Problem

[DavidCr]

I have a Charnwood W650 table saw that I bought second hand. My problem is that when ripping, the piece pulls away from the fence. I have adjusted the fence so that it is parallel to the blade. The fence also aligns perfectly with the mitre tracks on the table but still the piece pulls away from the fence. I suspect that the problem relates to the riving knife because if you are trimming a piece to size, where the material is not on both sides of the b the problem doesn't occur.

The riving knife appears to be in line with the blade.

Can someone tell me how to resolve this problem.

 

[Cabinetman]

I’m sure you will have had a good look at the riving knife and made sure it is central and seated properly, it’s not a problem I’ve ever had, I use two push sticks (one to push the wood against the fence ) so if you’re not using push sticks that might be why it’s wandering, we have just had two threads on here about the advisability of using push sticks and how dangerous push blocks can be, not sure if that applies. Ian

 

[MARK.B.]

You could try using a couple of feather boards to keep the stock down flat and concentrate on keeping it tight to the fence while guiding through. It may help or it may not but certainly worth a try

 

[shed9]

At what point does it pull away?

 

[Sandyn]

unlikely, but another sanity check to do is check the blade. Are the teeth equally sharp/blunt on both sides. Do you have another blade to try, to eliminate it as the cause.

 

[Trainee neophyte]

If you push the wood from from a point close to the fence, the workpiece will automatically steer itself away from the fence and cause a curved cut. If you push the workpiece from a point in line with the blade it should automatically steer itself towards the fence and solve the problem. If you are already doing this, I've not been much help.

 

[wallace]

Is the riving knife the correct one for the blade, ie does it match the kerf

 

[TRITON]

As above, use a feather board to apply pressure towards the fence.

Mind and use your long push sticks.

 

[Ttrees]

Is your table insert flush, presuming your stock is surfaced.
Could it be just tension being released in the timber?

 

[powertools]

If the fence is parallel to the blade then you are either using the wrong type of blade for the job, the blade is blunt or you are feeding the wood through too fast.

 

[Amateur]

Put a rule on one side of the blade and slowly push it towards the riving knife. Do the same on the opposite side. See if the gaps are the same gap, undersize, or over size, or just in line/slightly under.
This will tell you if the riving knife is
1. In the centre of the blade.
2 Off set from the blade
3 Oversize for the blade.

Remove the riving knife and see if it's bent.

Get a micrometer or vernier gauge and measure the thickness of the blade and the riving knife.
The riving knife should be slightly narrower.

If the blade is thinner you have two options.
find a blade supplier with the correct kerf for the riving knife.
Or, get a new riving knife.....
On some saws you will find that only one or maybe two produce kerfs of the correct thickness specified to match the fitted riving knife.
particularly in the 10 inch range.
For instance the Trend craft blades are spot on 3.2 mms kerf, if that's what you use.. While multi packs from Axminster and Silverline can be substantially thinner although marked up as 3.2mm and can cause problems ripping with a riving knife.

Its important you take the time to fully check out exactly what's on your saw especially as it's second hand.
I would also consider buying a clock gauge and block to check the locking mechanism sets the fence running parallel to the saw blade in several positions.
It will always come in useful in the future.

Someone suggested a new blade too, which should have been the first port of call setting up a new machine.
Before you buy one do the checks above.
This will tell you what the problem is.

 

[Amateur]

A lot of people remove the riving knife.
Primarily because it alleviates this problem.
Believe me the riving knife is there for safety purposes.
It may give you restrictions during certain operations but there are always alternative options that removing it.
My advice is don't remove it.
Ten fingers are better than five.

 

[DavidCr]

Thanks for all the feedback. After taking many measurements, I found that the blade (and the riving knife) was slightly out of parallel with the saw table. Once I had reset the table, the problem was sorted. I am quite surprised that such a small misalignment caused that much impact but that was definitely the problem. Again, thank you all for the feedback.