Table Saw Fence - Critical to be Square?

[Bugsysiegals]

I recently re-calibrated my Kapex, TS 55, and Table Saw blades to be square within 0.001" and am happy about that but noticed my Incra TS LS Joinery Fence is not perfectly square to the table.  In fact, how square it is to the table changes slightly depending whether it's 1", 12", 24", etc. away from the blade.  I've tried to split the difference so it's most square at 12" and therefore 0" and 24" are off by the same. 

I suppose I could tinker with the rails and whatnot to tighten this tolerance even more but I wonder how critical it is anyways.  For example, if I rip a panel with the TS 55 and it has a square edge, I place that edge up to the fence which is not perfectly square but has either top/bottom closer to the blade, the square stock will only be supported by that edge but as long as that edge is parallel to the blade, does it have any impact whatsoever on the squareness of the Table Saw cut?  In my mind, the only impact would be if I was standing a board up tall and pushing it against the fence at which point it would be leaning to some degree and have an affect, so this is more important for router table operations, but for ripping maybe not so critical?

 

[ChuckM]

If the fence is not square to the table while the saw blade is, how do you decide how far the fence is from the blade? When the blade height is at different points (to handle stock of different thicknesses), the distance between the fence and the blade becomes different.

I would prefer to rule out as many uncertain factors that may affect a cut as practicable when using my machines.

I'm not familiar with your fence, but mine (SawStop) can be tuned following the instructions in the user manual.

On the other hand, we all have different levels of tolerance. Your "not perfectly square" fence might be more than good enough for many other people.

 

[Bugsysiegals]

If the fence is not square to the table while the saw blade is, how do you decide how far the fence is from the blade? When the blade height is at different points (to handle stock of different thicknesses), the distance between the fence and the blade becomes different.

I would prefer to rule out as many uncertain factors that may affect a cut as practicable when using my machines.

I'm not familiar with your fence, but mine (SawStop) can be tuned following the instructions in the user manual.

To measure the distance of the fence from the blade, I rip a narrow piece of stock, measure with digital caliper, slide the magnetic rule where it needs to be, and reset the micro adjuster where it needs to be.  You're correct that the blade height affects the width but only if the top of the fence is closer to the blade than the bottom of the fence.  If the bottom of the fence is closer, the blade height and stock height should have no change in width, unless I'm missing something?

Obviously I'd like it as close as possible to square but there's many variables with the Incra fence to get everything perfectly setup ... I've done many of these but am wondering where I draw the line on good enough and not needing hours more tweaking for something insignificant ...
https://www.incrementaltools.com/INCRA_TS_LS_Joinery_System_32_Range_p/ls32-ts-wf.htm

 

[ChuckM]

If the cuts themselves come out fine to the desired level of accuracy, I wouldn't worry too much about the fence setting.

 

[Bugsysiegals]

If the cuts themselves come out fine to the desired level of accuracy, I wouldn't worry too much about the fence setting.

It seems we agree then that the only thing which is affected is distance, if the top of the fence is leaning towards the blade, and that it “shouldn’t” affect making square cuts?

 

[ChuckM]

Squareness shouldn't be an issue (except as you noted in the case of vertical cuts such as resawing). If the top angles towards the blade, when you cut two pieces of different thicknesses, they may come out with different widths.

I wonder if the fence tilts towards the blade, would this product alleviate your concern (price in Cdn): https://www.leevalley.com/en-ca/sho...32182-slippery-low-friction-tape?item=25U0401 ?

 

[Bugsysiegals]

Squareness shouldn't be an issue (except as you noted in the case of vertical cuts such as resawing). If the top angles towards the blade, when you cut two pieces of different thicknesses, they may come out with different widths.

Thanks [member=57948]ChuckM[/member]!  It's absolutely perfect at the blade but as you extend the fence away it's off by a maximum of 0.003".  While that;s not terrible, the top is closer to the blade, and so I'll shim it in order to have consistent widths at any board height.