How level is "level" for pool tables?

garczar

AzB Silver Member
Silver Member
I am most familiar with bar tables, which you have to lift up the slate to put the felt on.
And you're worried about WPA specs???? Please. Every top mechanic i've ever seen uses 12" machinists levels. Mark Gregory sometimes uses six at a time.
 

jviss

AzB Silver Member
Silver Member
A 12" Starrett Machinists Level has precision of 0.005 inches per foot.

For a regulation table that equates to 0.0225 inches across the width of the table.
How did you come up with this?


The WPA equipment specifications call for an overall flatness within .010 inches across the width of the table. Therefore the 12" Starrett Machinists Level is not accurate enough to do the job right.
You are confusing the specification for flatness of the slate with level of the playing surface.
 

garczar

AzB Silver Member
Silver Member
How did you come up with this?



You are confusing the specification for flatness of the slate with level of the playing surface.
Yep. Flat and level are NOT the same thing. Slates are machined so each piece is FLAT. When assembled they are LEVELED.
 

smashmouth

AzB Silver Member
Silver Member
there is a very recent bbc video featuring the table mechanics who set up the world snooker championship tables

worth searching for

my memory could be off but I believe they suggested a tolerance less that the thickness of a sheet of paper proven via an engineer's level
 

sbpoolleague

AzB Silver Member
Silver Member
Thanks for your reply. I think this is the first one that articulates a specification for level for the table, which you state, if I interpret it correctly, is 0,01º. If my trig serves me well, that's 0.002"/ft., which I think is too strict; it's less than the sensitivity of the machinist's level the pros use, which is 0.005"/ft. So, maybe you are off my a decimal point? A spec of 0.1º would be 0.021"/ft., which seems more reasonable to me, and corresponds to what I read in the Brunswick Gold Crown I 1961 service manual. )The Starrett model 98, 8", 0.005"/ft. level goes for about $150, new.)

You are right, I was off by a decimal point.

The WPA specs say "overall flatness within + .020 inches [.508 mm] lengthwise and + .010 inches [.254 mm] across the width"

Width of a regulation table is 54".
That makes the tolerance angle = arctan(0.1" / 54") = arctan(0.001852) = 0.106 degrees.

Still, the engineering levels are good enough but the regular store-bought levels are not.
 

sbpoolleague

AzB Silver Member
Silver Member
How did you come up with this?



You are confusing the specification for flatness of the slate with level of the playing surface.

Maybe I am confusing flatness with level here. But in the end, once you have a good slate, it's the level that you are worried about.

How did I come up with that? The online specs for the 12" level state 0.005". Since a regulation table is 4.5 times the width of the level, simply multiply 0.005" by 4.5 to get 0.0225".
 

sbpoolleague

AzB Silver Member
Silver Member
And you're worried about WPA specs???? Please. Every top mechanic i've ever seen uses 12" machinists levels. Mark Gregory sometimes uses six at a time.

You are right. Machinists levels are fine. I thought they were, and when I did my math and it showed they weren't, I was confused. I was off by a decimal point.

That doesn't detract from my main point in that an inexpensive store-bought level is never good enough to level a table.
 

spktur

AzB Silver Member
Silver Member
You are right, I was off by a decimal point.

The WPA specs say "overall flatness within + .020 inches [.508 mm] lengthwise and + .010 inches [.254 mm] across the width"

Width of a regulation table is 54".
That makes the tolerance angle = arctan(0.1" / 54") = arctan(0.001852) = 0.106 degrees.

Still, the engineering levels are good enough but the regular store-bought levels are not.

The correct dimension of the playing surface of a regulation 9 foot table is 50" x 100". Anything outside this would be under the rail.
 

9 Ball Fan

Darth Maximus
Silver Member
This is a surprisingly good thread. Very informative, vigorous discussion.

I'm almost surprised no one has tried to dump on the thread yet...

Great topic!!!
 

jviss

AzB Silver Member
Silver Member
This is a surprisingly good thread. Very informative, vigorous discussion.

I'm almost surprised no one has tried to dump on the thread yet...

Great topic!!!

Yes, thank goodness.

So, we've had a level discussion, but not much on a spec for the level of a table. I'm surprised this didn't appear in the WPA equipment standards, which are internationalized.

I am getting the impression that when pros set up tables using the right tools they get them well within the range that is undetectable while playing.
 

Rubik's Cube

Pool Ball Collector
Silver Member
Good evening, everyone. :)

The best method for me is to use a laser level. I place five steel measuring rules on the baize, one at each corner pocket and one in the centre of the table. I like the way this then allows tiny adjustments to be made until all five laser beams give an identical reading.

Best wishes,
RC.
 

ThinSlice

AzB Silver Member
Silver Member
That makes no sense whatsoever. So you cherried out the level on the naked table...then what? You have to lift the slate out, install the felt, then put the slate back, then re-level the table because you moved the slate.



Why would you have to lift the slate out? What type of table are you referring to that you would have to lift the slate out?


Sent from my iPhone using AzBilliards Forums
 

poolhustler

AzB Silver Member
Silver Member
I just do construction, so I deal with 1/8" per foot in 10 ft and 1/4" per foot so shit rolls downhill... the table levelling stuff... I leave that to the pro's :)
 

Patrick Johnson

Fish of the Day
Silver Member
You are right, I was off by a decimal point.

The WPA specs say "overall flatness within + .020 inches [.508 mm] lengthwise and + .010 inches [.254 mm] across the width"

Width of a regulation table is 54".
That makes the tolerance angle = arctan(0.1" / 54") = arctan(0.001852) = 0.106 degrees.

Still, the engineering levels are good enough but the regular store-bought levels are not.
Isn't there a mismatch there (in red) - making the angle 0.0106 degrees?

pj
chgo
 
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