Unisaw table flatness

[David Weaver]

This is just my opinion, and only that, but I think that's terrible. If they season the cast, I don't see how it could be out that far.

I don't know what Steel City uses as a flatness spec, but I recall reading something a while ago that said that they season tops for 6 or 8 months before they finish them off. Maybe I have them confused with someone else - who knows.

But one thing is for sure - you can't use any 0.015" tablesaw top to lap handplane soles.

My delta hybrid is just north of 0.008" hollow from front to back, and I wasn't pleased with that.

It's just a sign of the times, I guess - do it quickly and cheaply.

[Art Mann]

There is a reason surface plates are made of granite rather than cast iron. There is a reason the specifications for premium tablesaws are +/- 15 thousandths. I doubt it is due to sloppy grinding. We are all accustomed to wood being unstable, changing dimensions, twisting and warping. Why is it so hard to understand that cast iron will do the same thing on a tiny scale? It would be an interesting study to survey a bunch of the old Unisaws and PM66s to see how flat they are.

[Bruce Page]

The bottom line is - it makes no difference to the piece you are cutting if the table is out .015 or is dead flat perfect. Why do we want the manufactures to expend the time & effort to give us perfect when it is only going to cost us more money? I’d be willing to bet that even the legendary Northfield table saws are not perfectly flat. It just ain’t necessary.

[Gary Keedwell]

The bottom line is - it makes no difference to the piece you are cutting if the table is out .015 or is dead flat perfect. Why do we want the manufactures to expend the time & effort to give us perfect when it is only going to cost us more money? I’d be willing to bet that even the legendary Northfield table saws are not perfectly flat. It just ain’t necessary.

Yea, that's the ticket....Lets tell all the manufacturers to LOWER the standards so we can get it cheaper. Opssss To late...Taiwan is now making most of them.
Gary

[Bruce Page]

Yea, that's the ticket....Lets tell all the manufacturers to LOWER the standards so we can get it cheaper. Opssss To late...Taiwan is now making most of them.
Gary

Not suggesting that they lower standards. I’m suggesting that .015 is perfectly adequate. Everything manufactured today is manufactured to a tolerance. You should know with your background that the tighter the tolerance the more it costs to machine. I work in aerospace, where a component failure can cost millions, yet every component, every nut, bolt & washer was made to a tolerance. There’s no such thing as perfect, you can get close but you’re going to pay for it.

[Richard Wagner]

Well, I came here with a question about my Shopsmith Mark V Saw Table and I am now feeling pretty darn good. I was concerned about a .005"-.007" dip in the table in the area around the table insert. Without even discussing my Shopsmith, I now know that I have nothing to be concerned about. Many of you with expensive iron have the same problem or maybe even worse. Thank you. You have made my day.

[Bill White]

Just as a point of reference, I'm not usin' my TS top to lap a plane sole. That's for which granite or glass is used.
The very idea.......Water and lapping on a TS top? Come on!

Bill

[jim gossage]

Most of the time it will not matter but there are occasions where it might. I was once miter ripping 5 x 5" pieces of wood on my table saw to build mitered boxes. I had the same problem with a 0.012 inch dip around the blade. Since the pieces were fairly small, they would follow the dip and this would impart a slight curve to the miter cut. It was impossible to close the miters with this set up. I had to build a sled to correct this problem