How Flat is a Flat Table?

[lv2wdwrk]

[quote="keakap"]Ironically, the multi-porpoise thing seems to be the main sticking point, lately.
It is in the drill pres mode where a flat table is not just a nicety but an absolute necessity if one is to perform accurate hole making.
To me, the drill press is not there just because I get tired of making sloppy holes with a hand drill.

]
If making accurate holes is a problem in drill press mode, why not use horizontal boring with the fence locked in place to hold the object being drilled?

[keakap]

... Has anyone had any problem with any power tool with a table, that is related to how flat the table was??? ....

Funny, I don't remember thinking of this until Ed mentioned drill press ops. But now that I do, the answer is yes, indeed.
Making a custom jewelry box of my own design required drilling through all 7 layers to accept three alignment pins, and said alignment was absolutely critical to the design (floating rotating drawers).

Of course I turned to the Shopsmith (see, I sorta remember reading somewhere that it was also a quality drill press), as such drilling was impossible without a drill press. Not a toy drill press, not a "give or take", "good enough for gummint work", "cross yo fingers" drill press, but a real one.
The table was not flat but I did not know it. Even after the HOURS of extra work I had to do the get everything aligned and working (no time for a do-over) I didn't realize the table was the problem.

I was not happy, but blamed myself (doin somethin wrong, just don't know what).

If I'd known then, when the holes came out crooked, it was the SS, I would have sold it or taken it to the dump, without hesitation.

And dang, I just realized, that was the end of the drill press. 1996. I've never used it again. So disgusted I didn't realize when the "flat" problem was solved, many years later.

[keakap]

... IMHO, for woodworking, my tables are flat enough without attempting to measure for inconsistencies.

I was going to say yeah, measuring for inconsistencies just for the sake of measuring for inconsistencies would be kind of a sad project.

And then I realized that while inconsistencies may not in most cases negatively effect your work, in other cases measuring to find inconsistencies before you do the work could mebbe save you many lost hours and tons of frustration.

I think I would prefer, and probably wouldn't even mind much, being told or finding out that there were inconsistencies before starting on a serious project involving exact tolerances. I could do it another way or make alterations.

So, I dunno, prior to starting a project maybe there's something to be said for measuring for inconsistencies. After all, done right, t'would only need doing onct.

[keakap]

If making accurate holes is a problem in drill press mode, why not use horizontal boring with the fence locked in place to hold the object being drilled?

Yes, indeed. Another feather in the "Multi-porpoise Tool" cap.

Assuming one knew of the D-P mode problem beforehand. And the horizontal boring problems.
Still probably better than a hand-held I would think.

[JPG]

[quote="keakap"]Ironically, the multi-porpoise thing seems to be the main sticking point, lately.
It is in the drill pres mode where a flat table is not just a nicety but an absolute necessity if one is to perform accurate hole making.
To me, the drill press is not there just because I get tired of making sloppy holes with a hand drill.

]

Wonder how 'flat'/'perpendicular'(two planes) most consumer shop bound drill presses are??????

My point re the multi-purpose tool was relevant to the fact the table is movable relative to the axis of the drill chuck'. This requires precise alignment(stops etc.) to provide accurate drilling.

[dusty]

Wonder how 'flat'/'perpendicular'(two planes) most consumer shop bound drill presses are??????

My point re the multi-purpose tool was relevant to the fact the table is movable relative to the axis of the drill chuck'. This requires precise alignment(stops etc.) to provide accurate drilling.

Maybe I do not understand what you are telling me.

Using a piece of round steel bar in the drill chuck and measuring the relationship of that rod to the table top at 45° increments around the rod and finding them all to be 90° can I legitimately declare the table "flat" (enough) and square to the drill bit?

Note: At this point I would also expect one of the adjustable stops to be in contact with the table.

[JPG]

Maybe I do not understand what you are telling me.

Using a piece of round steel bar in the drill chuck and measuring the relationship of that rod to the table top at 45&#176]Note: At this point I would also expect one of the adjustable stops to be in contact with the table.[/SIZE]

If the stop screws are not adjusted properly, the table will not be perpendicular to the quill axis and the bar will not maintain 'contact'/constant clearance throughout the revolution. Granted this is about accurate drilling, not table flatness. The trunion rotation and the trunion/table screws also affect the 'accuracy' and possibly table 'flatness'.

The point I was trying to make re it being a 'multi-purpose' tool was that all these degrees of 'freedom' exist, and their respective stops affect the accuracy of any drilling. Most 'drill presses' allow rotating the table about the support post, and some allow 'tilting the table' side to side only.

P.S. They also usually have much smaller tables!!!

[dusty]

If the stop screws are not adjusted properly, the table will not be perpendicular to the quill axis and the bar will not maintain 'contact'/constant clearance throughout the revolution. Granted this is about accurate drilling, not table flatness. The trunion rotation and the trunion/table screws also affect the 'accuracy' and possibly table 'flatness'.

The point I was trying to make re it being a 'multi-purpose' tool was that all these degrees of 'freedom' exist, and their respective stops affect the accuracy of any drilling. Most 'drill presses' allow rotating the table about the support post, and some allow 'tilting the table' side to side only.

P.S. They also usually have much smaller tables!!!

Let me try this again, please.

If I back the table stops screws all the way in (no table stops) and then tilt the table so that it is square with the chucked rod (drill bit) and then check it as previously described - what more can I do?

It seems at that point "it is what it is".

Note: I know my table is NOT perfectly flat. The back, right corner is a little low (.004 "). I've shimmed at the trunnion bolts to get there.

[keakap]

Wonder how 'flat'/'perpendicular'(two planes) most consumer shop bound drill presses are??????

My point re the multi-purpose tool was relevant to the fact the table is movable relative to the axis of the drill chuck'. This requires precise alignment(stops etc.) to provide accurate drilling.

As to the 'wonder', I'd expect that within comparable ranges they would be as capable or slightly less so than the SS.

And that's taking into account the "movable" nature of the SS. With those easily achievable precise alignments & reasonable care with a flat table (a Must) I consider the SS D-P a high end tool.

But you pose an interesting query. What specs on flatitude in the general populace of D-P's?

(But whatever, it must be the real thing-- a mere emulation of flat is just so much flatulation, after all.)