Tables saw table flatness question...

[Patrick Walsh]

I purchased a new to me industrial SawStop a few months ago. I just now was able to get it into my shop due to all the snow. Anyway i purchased it in pieces for a smoking deal. It had a problem with the blade not wanting to raise or lower but that was a easy fix.

Anyway i got into my shop and setup today and all went well except one small detail. The main table is flat as can be as are the two cast iron side extension tables on their own. However after putting the extension tables on the top has some dish with the low spot being at the blade. A four foot level spanning the width of the table indicates about a 1/16 gap at the blade that peters out to nothing by the end of the two extension tables. The gap actually goes away about half way through the extension tables on either side.

On another forum i posted this same topic. It was suggested even very very expensive machines require shimming. From what i can figure if i shimmed the saw in a manner to resolve the issue i would put a shim between the the main table and extension tables left and right. My best figuring this would mean a substantial gap on the top of my table either side of the primary table.

thoughts?

is this like a deal breaker or will the saw function fine?

Oh and how do I post pictures?

[scott spencer]

Before doing anything, I'd try some test cuts first. Most deviations in the table top don't amount to a hill of beans where the rubber hits the road....if that's the case here, you're fine. If the cuts aren't square, then I would try shimming the wings....it's a very common adjustment on a new saw.

[Patrick Walsh]

So what just a shim at each bolt on the upside of the table. My guess is I'm gonna have some pretty ugly gaps to collect dust.

[Ethan Melad]

If I'm reading it right, this would indicate that the edges of either the main table or the extensions are not square to the top. i'd figure out where the issue lies, and then it may be a relatively inexpensive job for a metal/machine shop to square whichever edges need squaring up.
At the same time, a sawdust filled gap caused by shimming doesn't sound like a big deal to me.

[Phil Thien]

You don't need uber-thick shims to have a pronounced effect.

Loosen the bolts and slip some playing cards between the extensions and the main table, snug-up those bolts, and give that straight edge another try.

Once you determine the required thickness, you can make a continuous shim from masking tape. Multiple thicknesses may be required. But probably not so much that you'll ever notice it is there.

[Rich Riddle]

The honest question is, "does this mechanical deviation limit your abilities?" In other words is your work usually more out of tolerance than the machine is currently out of tolerance. If your work is never better than that deviation, then it doesn't matter. If your work is incredibly accurate, it might.

[Patrick Walsh]

For what i payed for the saw some playing cards or masking tape are no problem so long as i can get good cuts.

A machine shop is also a viable idea.

I know SawStop sells the tables. I think they are not that expensive. Still if i buy all three pieces to assure a flat top it could get expensive. One extension able not so bad. All of them well....

I did not run anything through the saw to see what I'm getting for cuts yet as the plug end is not the same as my 220 30amp outlet.

looks like i have more fun ahead for me next weekend!

[Patrick Walsh]

Yes my work tends to be pretty precise.

I figured this would be a problem and my intuition told me shims would be the answer.

Just bummed the saw is not perfect. What did i expect for $1600 and a machine made in 2005.

i just hope i dint have this problem with the new Felder jointer planer i purchased. Now or in ten years. Ill be pissed!




The honest question is, "does this mechanical deviation limit your abilities?" In other words is your work usually more out of tolerance than the machine is currently out of tolerance. If your work is never better than that deviation, then it doesn't matter. If your work is incredibly accurate, it might.

[scott spencer]

Shimming is very common...almost normal setup really. Again, if it's not affecting the cut, there's no reason to fret about it. Measure the cut first, measure the table later only if the cuts aren't good.

[Phil Thien]

Don't bother machining the edges.

Look at a good combination square, the machining required (and the cost).

Now ask yourself if you're going to find someone that can turn your table tops and edges into precise right angles, for a reasonable price.

Just shim the thing.

[glenn bradley]

I use the thin foil hvac tape as a shim. It stays put, can be run in a continuous strip, double layered if required and has worked for me on a few saws.

[Art Mann]

I owned a table saw that required shimming between the table and the wings to make the work surface flat. It was an old Craftsman contractor saw. The instructions that came with the saw told how to do it. If you buy new wings from Sawstop, you may very well see the same discrepancy. After all, these aren't machine tools but rather woodworking tools. 1/16 seems a little bit much but I doubt if you could measure the difference in cutting accuracy. If I were you, I would do some test cuts on various lengths of lumber to see if the dip makes a measurable difference before taking any corrective action.

[Joe Jensen]

Before doing anything, I'd try some test cuts first. Most deviations in the table top don't amount to a hill of beans where the rubber hits the road....if that's the case here, you're fine. If the cuts aren't square, then I would try shimming the wings....it's a very common adjustment on a new saw.

The geometry would suggest pretty thin shims. If it's 1/16" out in the middle of say 36", that's .125" over 36 inches or about .042" per ft. The edge where the wings bolt is about 1.5" tall. Thats 1/8 of a foot. So it should take 1/8 of the .042" or .006" shim. Super thin shim.

Try .005 and .006 feeler gauges as shims to see.

[Larry Frank]

Call SawStop and ask them the same question...the customer service is very good

[John Schweikert]

Have you attached the fence angle steel and backside angle steel? With the bolts that hold those two steel lengths not fully tightened, you can easily use a rubber mallet and manipulate any small deviations. Then tighten those bolts. The angle iron is very strong and will hold the cast iron tops flat. I did that with my PCS.

[Myk Rian]

Some people put way too much time in fretting the small stuff. There is no need to get OCD over this. A shim only a few thousandths thick is all you'll need.

[Jerome Stanek]

Are both extensions out or just one. Check from the outside edge of the extension to the far edge of the top on each side and see what extension is out more

[Art Mann]

You may already know this but you need a precision straight edge and feeler gauge to do the kind of precision leveling you want to do. A home made straight edge or cabinet ruler may give unreliable results.

[Kevin Jenness]

I look on most machine tools as kits- assembled parts that reguire some tuning to achieve the standards I want. Martin being the exception, in my experience. You didn't buy a Martin so get out the shim stock or a file.

[Ted Reischl]

The OP described it as a "dish" that is the worst closest to the blade. A "dish" to me is a curve.

Anyhow, when I bought my Delta years ago, I had one of those "dished" tops. I did not discover it until I was using a tenoning jig (also Delta). It gave me fits until I discovered what the problem was. I was new to woodworking and immediately figured it was something wrong with my technique.

Those were the good ol days. Delta sent me a new table top free. It was dead flat. The guy I talked to told me that actually my existing table was "in tolerance" but understood my plight.

BTW, over the years I learned not to flip the workpiece over to cut the other cheek as is shown by all the "experts". If all of your wood is perfectly the same thickness, that works. That is not reality. If the wood varies by as little as .005 that tenon goes from friction fit to slopping around in the mortise.

[Lee Schierer]

The geometry would suggest pretty thin shims. If it's 1/16" out in the middle of say 36", that's .125" over 36 inches or about .042" per ft. The edge where the wings bolt is about 1.5" tall. Thats 1/8 of a foot. So it should take 1/8 of the .042" or .006" shim. Super thin shim.

Try .005 and .006 feeler gauges as shims to see.

I agree, the shims would be very thin and shouldn't let any significant amount of sawdust to collect. Even if sawdust does accumulate, how often are you going to need to remove the wings?


Aluminum soda cans make excellent shims. Once you get the right thickness you can easily file down any amount that sticks up above the table surface. If you use the aluminum duct sealing tape, you can trim of the excess with a razor blade.

[Patrick Walsh]

Thank you all for the input.

i feel much better that this is not a deal breaker.

It was clear to me while putting the saw together thT shims would solve the problem.

My thought process was that it would leave small gaps in the table top and i really would prefer that to not be the case.

My other thought was if the deveation would not affect my work i could easily not let ti go and not worry about it.

I have yet to actually run the saw as i need to replace the cord as it does not match my current 30amp outlet. Yes i only have one and my dryer plugs into it.

Again thanks for the pointers. I dont know why but i feel much better.

[Pat Barry]

So the table top was flat and so were the extensions and now that you have it assembled the top is cupped. Either the top is cupped and you didn't notice or, you warped it by tightening it all up. I would therefore tell you to back to square one and verify the top is flat. Then reassemble it and don't overtorque the screws out of sequence. You should approach the tightening by doing it similar to torqueing head bolts on a car motor or tightening lug nuts. Continually check it for flatness until its done. If the top warps, then you should notice that and be able to report on results for possible further assistance. Good luck

[Lee Schierer]

So the table top was flat and so were the extensions and now that you have it assembled the top is cupped. Either the top is cupped and you didn't notice or, you warped it by tightening it all up. I would therefore tell you to back to square one and verify the top is flat. Then reassemble it and don't overtorque the screws out of sequence. You should approach the tightening by doing it similar to torqueing head bolts on a car motor or tightening lug nuts. Continually check it for flatness until its done. If the top warps, then you should notice that and be able to report on results for possible further assistance. Good luck

It is likely that the edges of the table or extensions are out of square with the tops bay just a fraction.

[Scott DelPorte]

I have cannibalized the leaves of a cheap set of feeler gauges to use as shims. Makes it easier for me to get the exact thickness I want. Just a suggestion.

[william watts]

I know this thread is 2 weeks old, and that you have an ICS but I experienced the same situation on a new PCS that I have been assembling. I called Saw Stop and they were very helpful. The solution was to loosen the bolts that hold the wings to the main table then align the joint at the wing/table in the center area by pressing up or down then tighten the 2 bolts in the center area. Then do the same for the front and back of wing/table joint and tighten the bolts . Move your attention to the side of the wing that is high, press down on the front of the wing until its level with the main table, then tighten the one bolt that holds it to the front angle iron. Repeat on all four corners pressing down/up and tightening bolts to the front and back angle irons. The flatness is achieved by using the angle iron to hold the tables in place. I had to press down really hard, no shims, no banging or hammering with a mallet is required.

Had I continued to read the separate instruction book on installing the fence this is covered, but not in the saw assembly instruction book. John in post 15 must have read the bookhttp://www.sawmillcreek.org/images/icons/icon7.png. With my limited ability I was able to get within .003 at the front and back of the tables. I am very happy with that and will soon be cutting 5/4 hard maple for twin beds.

Bill

[scott spencer]

Thank you all for the input.

i feel much better that this is not a deal breaker.

It was clear to me while putting the saw together thT shims would solve the problem.

My thought process was that it would leave small gaps in the table top and i really would prefer that to not be the case.

My other thought was if the deveation would not affect my work i could easily not let ti go and not worry about it.

I have yet to actually run the saw as i need to replace the cord as it does not match my current 30amp outlet. Yes i only have one and my dryer plugs into it.

Again thanks for the pointers. I dont know why but i feel much better.

Wondering how you made out Patrick?