Table flatness

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DLB
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Re: Table flatness

Post by DLB »

Spec for the SawStop Professional Cabinet Saw (PCS) models:
Table flatness measured diagonally: 0.010" Maximum gap
Source: https://www.sawstop.com/product/profess ... a30/#specs

Their Industrial Cabinet Saw is the same. Their lesser saws are: 0.016" for Contractor's, 0.033" for job site, and unspecified for Compact.

- David
Hobbyman2
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Re: Table flatness

Post by Hobbyman2 »

Tabletop: The tabletop is the most important part of the table saw and needs to be absolutely flat in order to provide the most accurate cut. Most saws have a cast-iron table that has been milled to within 1/1000th of an inch for flatness.
Be aware that this figure can be deceiving and that you need to check the saw for flatness before you decide to keep it. Some tables are so far from flat that a decent cut is impossible to make. Choosing a saw from a major manufacturer reduces your chances of getting one that doesn't have a flat table (though it doesn't eliminate them).
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RFGuy
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Re: Table flatness

Post by RFGuy »

DLB wrote: Thu Jan 05, 2023 4:08 pm Spec for the SawStop Professional Cabinet Saw (PCS) models:
Table flatness measured diagonally: 0.010" Maximum gap
Source: https://www.sawstop.com/product/profess ... a30/#specs

Their Industrial Cabinet Saw is the same. Their lesser saws are: 0.016" for Contractor's, 0.033" for job site, and unspecified for Compact.

- David
David,

Thanks. I tried looking this up for Powermatic, but can't seem to find it published in their TS manuals, but in lots of places online I see forum members quote that Powermatic has a spec of less than 0.010" for table flatness. Honestly that is good enough for me, i.e. if both Sawstop and Powermatic (two major industry leaders) both have the same spec of 0.010" flatness across the TS table then I have to believe it is for a reason. Granted this may be overkill for many users, but you have to understand that some woodworkers do more precision work. Model & pattern makers come to mind, but also anyone doing segmented pieces for woodturning or similar type work. Try doing an 8 sided (or larger) segmented woodturning with greater than a 0.010" dip and see how that turns out...sure you might be able to calibrate it all out with a perfect square depending on the dip location, but such a significant dip will likely confound both your alignment endeavors as well as getting accurate enough miters for that segmented turning. I still stand by my prior assertion that when you discovered 0.030" of flatness deviation that you did the right thing in trying to reduce it. JMO.
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BigSky
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Re: Table flatness

Post by BigSky »

very simple solution

If one needs extreme precision -

buy the right equipment

an axe won't do the trick

right tool for the task is a must
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SteveMaryland
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Re: Table flatness

Post by SteveMaryland »

Some relevant pages from Krulikowski, Fundamentals of Geometric Dimensioning & Tolerancing. Explains how flatness is defined and inspected.

My table is also out-of-flat by a small amount. I have considered tapping the table to attach some steel plate or angle underneath the table.
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