Is a .006 dish acceptable?

[Cliff Holmes]

I just picked up a new SawStop PCS and started assembling it. Naturally, I checked out the flatness of the cast iron (using a Veritas 3' straightedge).

The wings are impressively flat. On one wing, the back 1" rolls off .001. On the other wing, one corner falls off .001 over the last 3". Other than that, they're the flattest pieces of cast iron I've ever seen.

The main top is not quite so impressive. There's a dish in the center that starts halfway through the throat and increases so that the center of the back edge is .006 lower than the edges.

I'm inclined to let this slide, since the zero-clearance plate will support the wood perfectly level well past the blade. However, I want to make sure I'm not missing any reason this dish will be a problem.

[Tony Bilello]

I have never measured and top to any table saw I have ever owned. In the past, I dont know of anyone that ever did either. We were all fat, dumb and happy with what we had and never knew the difference. I think all these new digital gauges are like a plague that create discontent with our tools.
My suggestion would be to make several cuts at varying widths and thicknesses of boards that have already been S4S and check the results of you cuts by placing the cut boards edge to edge and see if they look like they are ready to be joined together straight from the saw. If your saw is lined up properly, they should be. That is to say that you should be able to cut boards and edge join them without a joiner. If you can do that, throw away your gauge.

[Cliff Holmes]

I'm not sure you understand just how big .006" is. You don't need a feeler gauge to see it, it's quite large.

[Paul Ryan]

Cliff,

You are fussing over nothing. .006 is nothing to worry about. And SS wouldn't do anything about it anyway. If you look at their specs. the tolerance is .01. .006 is less than a 1/128 dish. Your pencil mark when cutting could be off by 3 times tha much. Enjoy your saw.

[mreza Salav]

Do you understand that 0.006" is within their spec's?
My ICS SS has the same level of flatness. After I installed the wings, across two wings/table it has a about 0.02" deep. I could get it better if I had shimmed the wings, but what the heck, it is not going to affect quality of the cut IMO.

[Steven DeMars]

Human hair . . . . .

The below in inches - 0.001575" to 0.009843"

Your concern I believe was .006".

I think we are in that gray area right now. Are you bragging or complaining . . . :D

WIKIANSWERS:

"It can vary tremendously depending on race, and continent (Africans' average hair thickness is higher than Europeans', for example). It also depends if you talk about body hair or head hair. Hair from a human head is normally between .04 and .25 millimeters, averaging normally .1. Body hair depends on gender and even within individuals of the same gender and race it can be very different from an individual to another."

Don't do as I have done in the past and let one toy dull the shine on another. If you own anything that measures, calibrates, weighs, etc, talk to some one the uses that device for a living measuring, calibrating or weighing before trying to resolve a problem that does not exist.

Example:

Persons diagnosed with diabetes today is "unbelievably" higher that just 20 years ago. Why, new gadgets available to measure blood sugar. Result, lowered thresholds to be diagnosed as diabetic.

"As technology improves we get sicker".

And we scrutinize our toys far more carefully after paying big bucks for the privilege of owning something not built by a village idiot, former enemy or slave labor, but by a prideful American Craftsman . . . who still has a job . . . .

Steve

[Zach England]

That is a horrendous and unforgivable flaw. It will make your saw impossible to operate. Please send me the saw so I may ensure it is disposed of properly.

[Gerald Senburn]

Wow, could you guys be any more condescending? He said he didn't think it was a problem.

Cliff, I agree with you that .006 is nothing to worry about in this case, because the throat plate will take care of it.

Paul, you can't be serious that .01 would be acceptable. A .01 dish would translate into an almost 3 degree error. I think most of us would be screaming bloody murder if our saws were producing an error that large. Especially if we had just paid $3k for that saw :eek:

[Brandon Weiss]

"Naturally, I checked out the flatness of the cast iron (using a Veritas 3' straightedge)."

When did precision measurement become a natural step of tool assembly for a wood shop?

Tony has an excellent point. We now look at our tools with gauges that take measurements many times more accurate than gauges of years ago (available to the little guy that is). Nothing, nothing, nothing is ever perfectly flat. If it is, I guarantee you it isn't affordable to any of us. You just have to continue to get more precise measuring devices to eventually find that GASP! it's not perfectly flat!

I don't have a planer so I could be wrong in this, but if you have a planer, take a piece of wood, cut it in half, and plane both pieces individually. Plane one, shut the machine off, plane the other. Not an uncommon operation in woodworking. Measure the two pieces with the same level of precision you've just measured your table saw top. How much of a difference is there? It doesn't take much to get a difference of 0.006". How much do you think your piece of wood will expand/contract over it's life?

I will never buy a straightedge because I don't need anything that straight. I'm not machining 1-2-3 blocks, I'm woodworking. I know there are many professionals here but your speaking in tolerances used in machine shops, not woodshops. I recommend that if you are so concerned with perfect flatness, you begin your tool research by figuring out what tolerances the company uses for its design models, machining operations, and assemblies. One influences the other, influences the other, so on. Even if you have something that's out of the company tolerances, do you honestly think 0.006 matters? I bet machine vibration could reach 0.006" if measured.

I always get a chuckle out of the posts here which talk about measuring things down to 0.001".

Sorry, an Engineer's rant and rave there for a second....

"Other than that, they're the flattest pieces of cast iron I've ever seen."

You said it yourself. Be impressed with what your nice new SS is. Congrats on your purchase.

[Ken Fitzgerald]

Gerald,

I suggest that if you contact most of the major manufacturers of saws, you will find that is their specification.

[Dan Friedrichs]

I don't have a planer so I could be wrong in this, but if you have a planer, take a piece of wood, cut it in half, and plane both pieces individually. Plane one, shut the machine off, plane the other. Not an uncommon operation in woodworking. Measure the two pieces with the same level of precision you've just measured your table saw top. How much of a difference is there?

Doing that test on my absolutely-beat-to-heck-and-back Dewalt lunchbox planer will produce 2 pieces of wood that are within 0.002" of each other (I've measured).

0.006" isn't insignificant. It's easily the difference between a tennon fitting snugly into a mortise and needing to be shimmed.

I'd be the slightest bit disappointed, but it's within their spec, so there's nothing you can do about it.

[Brandon Weiss]

Doing that test on my absolutely-beat-to-heck-and-back Dewalt lunchbox planer will produce 2 pieces of wood that are within 0.002" of each other (I've measured).

0.006" isn't insignificant. It's easily the difference between a tennon fitting snugly into a mortise and needing to be shimmed.

I'd be the slightest bit disappointed, but it's within their spec, so there's nothing you can do about it.

I would love to see a planer do within 0.002". I guess I really need to get one of those. They sound like incredible machines. Maybe you guys are right. Be disappointed in your new SS that is 0.006" out of tolerance. Please thank Zach for offering to take that POS off of your hands.

Out of curiosity, what do you use to shim 0.006"? And what happens if you don't shim it? You either apply glue or fasteners anyways, right?

Do any table saws provide fence adjustments down to the 0.001"? If they do, better get working on the 0.0001" adjustment because that will be demanded next. I wonder what thread pitch the height adjustment screws are. Those will have to be modified so that they can be turned in the same increments.

In my eyes, I would be more impressed with what my saw does when it's on. Not when it's off. Cliff, I bet you'll forget all about that 0.006" measurement after a couple of cuts on the saw. Again, congrats on the new piece of equipment.:)

[Cliff Holmes]

Do any table saws provide fence adjustments down to the 0.001"?

http://incra.com/product_tsf_lsts.htm

[Dan Friedrichs]

I would love to see a planer do within 0.002". I guess I really need to get one of those. They sound like incredible machines.

Not really. Mine is a piece of junk otherwise, but I just spent a little time adjusting it.



Out of curiosity, what do you use to shim 0.006"? And what happens if you don't shim it? You either apply glue or fasteners anyways, right?

A piece of 20lb paper is 0.0038". You could just apply glue and hope it swells, but I like tight fitting tennons..



I think 0.006" in a table saw surface is probably negligible. But if you think 0.006" is ALWAYS nothing to worry about, I'd challenge you to go find two boards that are 0.006" difference in thickness, glue them up, and see what you think of that joint (or if you don't want to do that, just fold a sheet of printer paper in half and rub your finger across it along a flat surface). It's not a huge error, but personally, I'd rather get my tools adjusted and aligned to eliminate it, rather than dealing with sanding or scraping later.

[Glen Butler]

.006 is within their specs as we have so blatantly heard, (I thought we were above this on SMC) but across how many feet. If a dip like that was narrow, encompassing not much more than the width of the throat, it could cause a problem in cut quality cause the wood would be forced down and vibrate as the teeth hit it. But nonetheless the dip starts behind the front of the sawblade so it shouldn't be a problem.

[Paul Ryan]

Paul, you can't be serious that .01 would be acceptable. A .01 dish would translate into an almost 3 degree error. I think most of us would be screaming bloody murder if our saws were producing an error that large. Especially if we had just paid $3k for that saw :eek:

Gerald,

.01 is not much. That is 10 1/1000's of an inch. That is the tollarance for the flatness of the top. And as Ken spoke of earlier that is the standard spec for most manufacturers. I didn't measure my top because frankly I didnt care. I checked the blade to miter slot, and dialed in the fence that is it. And the saw produces very very nice cuts. I will bet if you check some of the older saws, hybrid saws, and crontractor saws. With the table mounted trunions you will find a much larger dip over time. The weight of the trunions and motor hanging off the table gradually pulls down the center of the table. But many many people make great pieces from saws like those.

I really think the measurements that are often made are totally rediculous. A straight endge and a light is really all you need to produce furniture. You dont need to be measuring down to the .000000000000001 of an inch. And table tops unless they have a very large crown really wont effect things that much. Wood moves more than .01 over time. Just relax everyone dont worry so much about these measurements and go enjoy your tools.

[mreza Salav]

A .01 dish would translate into an almost 3 degree error.

May I ask, how did you calculate that 3 degree error?!!!!
Amazing...

0.006" is across the table which is 44". Say it was 0.01".
So, 0.01" height vs. 22" (half the table), if you do the math, it gives a degree of about 0.02604.

Do I care for that? not the slightest.

Edit: did the calculations for .01"

[Cliff Holmes]

He didn't say .006, he said .01 (manufacturers acceptable error). I can see where dropping one end of a narrow board by .01 would tilt it by a couple degrees. And *I* didn't say the dish was across the whole table, it's about 6-8 inches wide.

Jeez, I really didn't think this would be another thread degenerating into a foaming-at-the-mouth session. I just asked a simple question.

[mreza Salav]

He didn't say .006, he said .01 (manufacturers acceptable error). I can see where dropping one end of a narrow board by .01 would tilt it by a couple degrees. And *I* didn't say the dish was across the whole table, it's about 6-8 inches wide.

Jeez, I really didn't think this would be another thread degenerating into a foaming-at-the-mouth session. I just asked a simple question.

You'll get over it Cliff, it really won't affect your woodworking.
As I said, if you check the manual it is within the tolerance of the saw.

BTW, even if it deeps 0.01" across only 4" the angle will be:
arctan(0.01/4)*180/pi= 0.1432, which is less than 0.15 degree.

[Mark Carlson]

Hi Cliff,

When I bought my General 650 from Eagle Tools the technician checked the tops flatness and found some high and low spots. The biggest around .004 or .005. I thought that was fine and bought it. The saw works flawlessly and imagine that most saws fall into this range.

Congratulations on your new saw. I'm happy with the General but would have bought the SS if it had been available.

~mark

[Shawn Pixley]

You're working with wood, right? Forget about it and make some sawdust.

"Not everything that counts can be counted. Not everything that can be counted, counts." Einstein

[Cliff Holmes]

BTW, even if it deeps 0.01" across only 4" the angle will be:
arctan(0.01/4)*180/pi= 0.1432, which is less than 0.15 degree.

Just for fun, that simplifies to arcsin(0.01/4) :)

[Mitchell Andrus]

Temperature matters. Measure again on a 90 degree day.

I also agree with most posts, not a worry.
.

[Cliff Holmes]

I am an HTML and internet browser expert. Click here for more info.

Heh, that's funny ...

[Clifford Mescher]

Doing that test on my absolutely-beat-to-heck-and-back Dewalt lunchbox planer will produce 2 pieces of wood that are within 0.002" of each other (I've measured).

0.006" isn't insignificant. It's easily the difference between a tennon fitting snugly into a mortise and needing to be shimmed.

I'd be the slightest bit disappointed, but it's within their spec, so there's nothing you can do about it.
You are absolutely right. You glue two boards together that are .006 difference, you will see the step. Most woodworker do work within .0002. They just accomplish it with scrapers and sanding. Clifford.

[John Thompson]

I have worked wood on six various TS's for going on 39 years Cliff.. a .006 dip didn't make a difference in 1972 nor does it today IMO. I had a TS for 4 years that had a .012 dip in the table away from the blade. 18 large carcass pieces came off that saw and many tenons were cut on it as M & T is my main joint.

.006 is within manufacturers tolerance and within reason as cast iron isn't perfect. You could spend an extra $100 + and have the top ground at a local shop but.... you won't notice any significant difference if you do IMO.

Regards...

[glenn bradley]

All humor aside, well known makers Grizzly and Steel City/Orion) state .008" as their tolerance. That is a lot (or not) depending on what you do and how you use your saw. My 'Orion' ZipCode saw was .004" and I was able to correct that a bit with shimming but now realize the effort was a bit "over the top" and netted me little.

Four thousandths of an inch is about the thickness of a piece of quality typing paper. A .008" gap on an exposed dovetail or dado joint would look amateurish but, I rarely try to fit my joinery right off the machine; wood moves. I would prefer better from a company that gets so much praise but, I would bet you are within tolerance and well within the limits of a usable saw. A call to SS customer service could confirm this. Go forth and be happy ;-)

[Sam Layton]

Cliff,

I don't know if it is good or bad, or will make a difference. I do know that if I paid as much money as you did for a quality tool, it would bother me. I would at least call them, and have your concern on the record if a problem arises.

Just my 2 cents, Sam

[Ken Fitzgerald]

According to the SS Contractor saw owners manual,

Table flatness measured diagonally.....0.016" maximum gap.


0.006" is within spec.


On their cabinet saw models, the spec is 0.010".

[harry strasil]

OT a bit, and maybe I should keep my typing to myself, but aircraft parts have the highest tolerances or standards. I toured Sunstrands mfg facility for Hydraulic pumps one time and the aircraft pump bodies are lapped to within .00001 and .00002 for squareness, that is in Millionths of an inch. And the only machines they found that would keep those tolerances were Special War Machinery made for WW2 production.

[Ken Fitzgerald]

Harry,

Glenn Clabo and a bunch of other submariners might argue highest specifications statement with you.

It caused me a lot of problems the short period of time I was on a submarine tender as I owned the "Sub-Safe" safe.

[Stephen Edwards]

I think it's a fair and reasonable question. I also think that you've been given some advice, not to worry about it.

Some of the nicest work that I've done, (granted that I'll always be an amateur woodworker), was done on 1960s era Craftsman machines.

Enjoy your new saw!

Best Wishes,

[Mitchell Andrus]

Heh, that's funny ...

Wha........?
.

[Bob Wingard]

Sell it and buy a Bridgeport .. .. probably put a few $$$ in your pocket too.

But then, you ARE cutting WOOD which moves with temp. & humidity. Considering the amount (0.006") and location of your "dip" .. exactly what effects would you expect due to the "problem" area ??

Rip ?? Crosscut ?? Dados ?? Molding ?? What detrimental effect could you possibly experience in any if these typical operations ??

[Cliff Holmes]

What detrimental effect could you possibly experience in any if these typical operations ??

Jeez, did you even read the original post? I said I didn't think it would be a problem. Why do so many of you insist on implying I'm a moron for even asking the question?

[Dave Verstraete]

Cliff
Go make some sawdust. These guys will be beating this "dead horse" for a while longer.:D Besides, if the cast table is as "green " as most, it will probably change in the next year anyway!!

[Brian Kent]

Jeez, did you even read the original post? I said I didn't think it would be a problem. Why do so many of you insist on implying I'm a moron for even asking the question?

Cliff, these emotional responses are as hilarious as the emotional responses to your great decision to buy a Sawstop. Maybe just for fun you could go over to Neanderthal Forum and say you like Lee Valley better than Lie Nielsen (or the other way around). :rolleyes:

Frankly, it would bug me unless I got into making things and found out is was not noticeable.

But it would bug me.

At night, I would lie awake.







Thinking.













Remembering how much it cost.


















.006

[Thomas Marr]

This is an interesting discussion.

I wish someone would try an experiment. Measure the table flatness in the center, then take a weight, say 15 lbs, and place it on the table and measure again. When I measured the run out on my drill press, I was amazed at how much I could change the reading by applying a little side pressure to the spindle (Powermatic 1150). I suspect the middle of table saw tops are subject to the same effect. Maybe try the same thing with fence deflection. I bet the results will be surprising and confirm, once again, that technique matters more the equipment.

[Cliff Holmes]

Maybe just for fun you could go over to Neanderthal Forum and say you like Lee Valley better than Lie Nielsen

I get it from all sides as it is. I own Grizzly, so I must be a cheap bastard who values crap. On the other hand, I have a SawStop, so I'm a sucker for marketing hype. And then, good Lord, I own some Festool stuff, so I must be an elitist with more money than brains.

I just can't win ... :(

[Paul Grant]

I get it from all sides as it is. I own Grizzly, so I must be a cheap skate who values junk. On the other hand, I have a SawStop, so I'm a sucker for marketing hype. And then, good Lord, I own some Festool stuff, so I must be an elitist with more money than brains.

I just can't win ... :(

Now that's funny.......;)

[Andy McCormick]

Well if you end up making a mistake on a project you can just blame the inacuracy of the tools you work with.:D

[Glen Butler]

Oh Brian that is the hardest I have laughed in a while. Good Post.

[Gary Herrmann]

I'm guessing Cliff is a bit concerned because he just shelled out good money and he found a dish. He posted about it because he wanted to get it off his chest, but based on his original post, I'd say he isn't too worried about it.

Cliff, congrats on your new saw. I'm sure you'll enjoy using it for years to come.

Gary, who hopes he can avoid dragging out his straightedge next time he makes a major purchase...

[Cliff Holmes]

I'm guessing Cliff is a bit concerned because he just shelled out good money and he found a dish. He posted about it because he wanted to get it off his chest, but based on his original post, I'd say he isn't too worried about it.

I'd say that's a pretty good synopsis. Since I just paid triple what I paid for my Grizzly, I really expected the SS to be at least as good in all areas if not considerably better. I've already found a several areas where it falls short. Nothing major, but irksome nonetheless.

[Lee Schierer]

As my grandfather used to say...."It's not the quality of the tools, it's the skill of the craftsman using them that really counts." Let's go make some quality wood projects.

I would suggest a nice polite letter to Saw Stop and tell them what you've found. If they don't think it is a big deal then neither should you.

[Cliff Holmes]

Well, yes, but along the same lines you can drive nails with a pair of pliers with enough practice and skill, but it's far better to use a hammer. If you're brand-new car had a constant drift to the left, you could compensate with diligence and skill, but you shouldn't have to. As I said in the original post, I *don't* think it's an issue but I wanted confirmation that I hadn't missed something.

As for writing SawStop, I did. They said that given the position of the dish it shouldn't be an issue.

[Ken Fitzgerald]

Cliff,

Given it's within the manufacturer's specifications and the extremely small amount I think it's not worth fretting over.

The main advantage of the SS over the saw you had is the safety factor.

The other point.....wood is much more dynamic than metals and most plastics. You cut a piece of wood...you are releasing built up energy and the wood itself can move 0.006". That is just a little less than 1/128th of an inch.

I wouldn't spend much time worrying about it. There are a lot of more important things in life that deserve our time, effort and concern.

JMHO.

[Lee Schierer]

As for writing SawStop, I did. They said that given the position of the dish it shouldn't be an issue.

Obviously you are looking for something more than what the majority of the responders and Saw Stop can offer you. I suggest you either return the saw or move on.

[Chip Lindley]

Cliff, you bought your new SawStop just in the nick of time! (Pun Intended) Undue fretting and stress can and does cause inattention while performing woodworking operations on power tools.

The chance of you suffering an incident while at the SawStop has been magnified many-fold because of your distrust of the accuracy of the machine you will be operating.

One contributor above said it BEST! Back in the day, we were all too dumb to contemplate such minute discrepancies within the realm of woodworking. We were just happy to have A tablesaw! But, the availability of digital instruments, formerly employed only by metal machinists, changed all that! .03125" replaced 1/32"

Put your new SawStop through it's paces Cliff. If your quality of work suffers, compared with your former TS, return the SS for a refund! There is, after all, quite a nice long warranty on the SawStop. At that price, there oughta be!~

[Cliff Holmes]

I suggest you either return the saw or move on

I'm trying to move on, but you people won't shut up about it.

[Roger Benton]

Wow.

I hope when I ask a simple question about something I'm not sure of concerning something I just dropped major coin on nobody jumps down my throat like this!

[mreza Salav]

I'm trying to move on, but you people won't shut up about it.

now honestly, do you really think it's going to perform as expected?


ducking and running :D:D:D

[harry strasil]

1.you never stated if the new one is better than the old one.

2. I think most thought you were joking, worrying about such a trivial measurment that was with in mfg specs.

3. probably cabin fever is running rampant, and its human nature to make a mountain out of an ant hill, just to watch others reactions.

4. if all the ones who gave good advise just shut up, the can of worms will dry out and blow away.

5. that's my view and I'm sticking to it.

6. bye, there is too much work to be done to play like spoiled children.

7. I am unsubscribing from this thread. its getting childish.

[Brian Kent]

Now that we've milked this one to death, what do y'all want to talk about?

[Brandon Weiss]

Opinions are not always nice. And that's exactly what you ask for when you post on this site. Opinionated discussions often get a little heated. You can't get upset because the answer you got to the question you asked wasn't what you wanted it to be. Sometimes a few heated opinion discussions are needed to bring us all back to reality. The best part about these opinions is that they are....opinions. Not rights or wrongs. So, take these posts with a grain of salt and be open to what these folks have said or consider us all idiots and kick yourself for asking. Either way, brush it off, don't let it get to you. Enjoy your new saw!

And that's my....opinion.....

[Ken Fitzgerald]

This dead horse has been beat enough.