Table Difficulty Factor (TDF) for measuring table "toughness"

Poolmanis said:

Yeah I know. Cloth is 4 months old now. But table played tight even with brand new cloth + rail cloths.

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Maybe the vertical angle of the facing is weird. That factor is not taken into consideration because it usually is not an issue.

Poolmanis said:

That online thing did not have any angle stuff on it?
I thought it was automatically calculated with pocket throat measurement.

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The horizontal pocket facing angle is automatically accounted for by the pocket mouth and throat measurements, but you can also measure the angle directly as a check. For more info, see the illustrations and tables in the first post of the thread.

Poolmanis said:

Also was pocket slate deepness measurement taken from middle of pocket or how?

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All of the measurements (including shelf depth) are defined in the following illustration:


Shelf depth is measured in the center of the pocket.

Regards,
Dave

nateobot said:

7' custom made from about 20 years ago.

Mouth: 4 3/8
Throat: 3 7/8
Shelf: 1 3/4

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Thank you for posting. I've added the following to the first post:

nateobot -- 7':0.85 -- 4 3/8":1.05 -- 1/2":0.95 -- 1 3/4":1.00 -- 0.85 (custom-made)

Regards,
Dave

Cardigan Kid said:

Looks like I made an error...
I have a correction to my shelf depth, I remeasured all corners and averaged 1 5/16".
After factoring that into your excel calculator, my TDF factor jumped up to 1.09.

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Here's what I get:

Cardigan Kid -- 9':1.00 -- 4 1/4":1.10 -- 0.45":0.99 -- 1 5/16":0.99 -- 1.08 (GC II)

I've made the correction on the first post.

Thanks for the update.

Cardigan Kid said:

Also, did you want us to measure random pool hall tables? Because I can collect some measurements around town.

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... definitely, especially if any of the tables are particularly noteworthy (e.g., if they play very tough, or very easy, or just "differently") or different from ones already on the list.

Cardigan Kid said:

I think this is groundbreaking in the world of pool, like the Accustats TPA, it should become commonplace.

I believe sports become more sophisticated when statistics become more abundant. Your TDF is another step towards the advancement of our sport.

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Thank you for your kind and supportive comments.

Best regards,
Dave

pocket said:

9'
4 3/16" Mouth
3 3/4" Throat
1 7/8" Shelf

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Thanks. Here's what I get:

pocket -- 9':1.00 -- 4 3/16":1.10 -- 7/16":0.99 -- 1 7/8":1.03 -- 1.12 (unknown)

Please post the table make/model so I can add it.

Thanks,
Dave

chevybob20 said:

9ft Centennial. Rail work was performed by Mark Gregory.

Mouth Opening = 4 1/8"

Throat = 3 1/4

Shelf Depth = 1.0"

Because the Mouth opening is at a midpoint I averaged the two TDF results of 1.12 and 1.35. So I think the TDF for my table is 1.23.

Let me know if I did the math correctly and thank you Dr. Dave.

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Here's what I get with the spreadsheet calculator:

chevybob20 -- 9':1.00 -- 4 1/8":1.15 -- 7/8":1.05 -- 1":0.98 -- 1.18 (Mark Gregory modified Centennial)

Wow. That's a tough table!

Thanks for posting,
Dave

Here's the latest:

Measurements and data reported by AZB users for table difficulty factor (TDF), based on the table size factor (TSF), pocket size factor (PSF), pocket angle factor (PAF), and pocket shelf factor (PLF):

name -- table_size:TSF -- pocket_mouth_sizeSF -- mouth-throat_differenceAF -- shelf_depthLF -- TDF (table description)
Vahmurka -- 12':1.25 -- 7.2cm:1.55 -- 125deg:0.97 -- 25mm:0.98 -- 1.84 (12ft Russian pyramid table)
dr_dave -- 10':1.10 -- 4":1.20 -- 3/4":1.02 -- 1 7/8":1.03 -- 1.39 (fictitious tough 10' table example)
Bob Dixon -- 9':1.00 -- 4":1.20 -- 145deg:1.14 -- 1 5/8":1.00 -- 1.37 (Pool Sharks, Las Vegas, money table, Diamond Pro-Am, red logo, Ernesto Dominguez-modified)
dr_dave -- 9':1.00 -- 3 7/8":1.25 -- 5/8":1.00 -- 2 1/8":1.07 -- 1.34 (fictitious example "B")
Bonus Ball -- 9':1.00 -- 3 7/8":1.25 -- 1/8":0.97 -- 3/4":0.98 -- 1.19 (Bonus Ball table)
chevybob20 -- 9':1.00 -- 4 1/8":1.15 -- 7/8":1.05 -- 1":0.98 -- 1.18 (Mark Gregory modified Centennial)
MahnaMahna -- 10':1.10 -- 5 1/2":0.85 -- 2":1.09 -- 2 1/2": 1.15 -- 1.17 (snooker table poorly converted into a pool table)
Qaddiction -- 9':1.00 -- 4 1/8":1.15 -- 3/4":1.02 -- 1 3/8":0.99 -- 1.16 (Diamond)
rexus31 -- 9':1.00 -- 4":1.20 -- 3/8":0.98 -- 1":0.98 -- 1.15 (mid to late 50's AMF Commercial Model similar to a Brunswick Anniversary/Sport King)
FatBoy -- 9':1.00 -- 4":1.20 -- 1/4":0.97 -- 1":0.98 -- 1.14 (Ernesto-Dominguez-modified GC)
TATE -- 9':1.00 -- 4":1.20 -- 1/4":0.97 -- 7/8":0.98 -- 1.14 (Ernesto-Dominguez-modified GC)
pocket -- 9':1.00 -- 4 3/16":1.10 -- 7/16":0.99 -- 1 7/8":1.03 -- 1.12 (unknown)
Neil -- 7':0.85 -- 4 1/8":1.15 -- 1 1/4":1.14 -- 1 3/8":0.99 -- 1.10 (modified Valley "bar box")
Cardigan Kid -- 9':1.00 -- 4 1/4":1.10 -- 0.45":0.99 -- 1 5/16":0.99 -- 1.08 (GC II)
cigardave -- 9':1.00 -- 4 1/2":1.00 -- 1":1.07 -- 1 3/4":1.00 -- 1.07 (typical Pro-Cut Diamond)
Pool Hustler -- 9':1.00 -- 4 1/4":1.10 -- 1/4":0.97 -- 15/16":0.98 -- 1.05 (modified GC, measured by rexus31)
JC -- 9':1.00 -- 4 7/16":1.00 -- 143deg:1.07 -- 1 3/8":0.98 -- 1.05 ("Cobrasized" GC III)
SloMoHolic -- 9':1.00 -- 4 1/2":1.00 -- 7/8":1.04 -- 1 3/8":0.98 -- 1.02 (2005 Diamond Pro with ProCut pockets and Red-label rails)
"standard" table -- 9':1.00 -- 4 7/16":1.00 -- 9/16":1.00 -- 1 5/8":1.00 -- 1.00 (average-difficulty table)
MVPCues -- 9':1.00 -- 4 1/2":1.00 -- 1/2":0.98 -- 1 5/8":1.00 -- 0.98 (Antique Brunswick Jefferson, circa 1900)
oldschool1478 -- 9':1.00 -- 4 1/2":1.00 -- 0.625":1.00 -- 1.5":0.98 -- 0.98 (updated Red Badge Diamond Pro)
dr_dave -- 9':1.00 -- 5": 0.91 -- 1 1/8":1.10 -- 1 3/8":0.98 -- 0.98 (old GC II at MatchUps, Fort Collins)
BryanB -- 9':1.00 -- 4 1/2":1.00 -- 3/4":1.02 -- 1 1/4":0.95 -- 0.97 (1931 Brunswick with double shimmed pockets)
Vahmurka -- 9':1.0 -- 12.5cm:0.91 -- 20mm:1.04 -- 45mm:1.03 -- 0.97 (Brunswick Metro)
mamics -- 9':1.00 -- 4 11/16":0.95 -- 143deg:1.07 -- 1 3/16":0.95 -- 0.97 (no-name "Chinese Cheapie" with Uylin cushions)
dzcues -- 9':1.00 -- 4 7/8":0.91 -- 11/16":1.02 -- 1 15/16":1.03 -- 0.96 (typical League-Cut Diamond)
dzcues -- 9':1.00 -- 5":0.91 -- 15/16":1.07 -- 1 1/2":0.98 -- 0.95 (Gandy Big G)
Sloppy Pockets -- 8'+:0.95 -- 5":0.91 -- 1 1/8":1.10 -- 1 3/4":1.00 -- 0.95 (A.E. Schmidt)
44Runner -- 8'+/-:0.925 -- 4 3/8":1.05 -- 3/4":1.02 -- 1":0.95 -- 0.94 (8' Diamond Pro-Am - blue label)
Poolmanis -- 9':1.00 -- 4.4":1.00 -- 0.47":0.98 -- 1.19":0.95 -- 0.93 (modified SAM)
frigopie -- 9':1.00 -- 11.5cm:0.95 -- 138.7deg:0.98 -- 3.5cm:0.98 -- 0.91 (Eurotour Dynamic III)
12squared -- 9':1.00 -- 4 7/8":0.91 -- 3/4":1.02 -- 1 1/2":0.98 -- 0.91 (GC home table)
iusedtoberich -- 9':1.00 -- 5 1/8":0.88 -- 1":1.05 -- 1 1/2":0.97 -- 0.90 (GC)
MSchaffer -- 9':1.00 -- 5 1/8":0.88 -- 3/4":1.01 -- 1 3/4":1.00 -- 0.89 (GC II)
mfinkelstein3 -- 9':1.00 -- 5 1/8":0.88 -- 7/8":1.03 -- 1 1/2": 0.97 -- 0.88 (GC III)
StraightPoolIU -- 9':1.00 -- 4 7/8":0.91 -- 3/4":1.02 -- 1 1/4":0.95 -- 0.88 (GC I)
Vahmurka -- 9':1.00 -- 5 1/8":0.88 -- 7/8":1.03 -- 1 1/2": 0.97 -- 0.88 (GC)
Dopc -- 8':0.90 -- 4 1/2":1.00 -- 3/4":1.02 -- 1 1/4":0.95 -- 0.87 (8' Connelly Kayenta)
SloMoHolic -- 8':0.90 -- 4 3/4":0.95 -- 3/4":1.02 -- 1 5/8":1.00 -- 0.87 (old 8' Brunswick Medalist league table)
RobMan -- 9':1.0 -- 5": 0.88 -- 3/4":1.01 -- 1.5":0.97 -- 0.86 (GC)
SloMoHolic -- 8'+:0.95 -- 4 7/8":0.91 -- 7/8":1.04 -- 1 1/4":0.95 -- 0.85 (Brunswick Medalist at Stardust Club in Manchaca, TX)
nateobot -- 7':0.85 -- 4 3/8":1.05 -- 1/2":0.95 -- 1 3/4":1.00 -- 0.85 (custom-made)
dr_dave -- 8':0.90 -- 4 3/4":0.95 -- 5/8":1.00 -- 1 3/8":0.98 -- 0.84 (8' Connelly home table)
BRussell -- 8':0.90 -- 5":0.91 -- 13/16":1.04 -- 1 1/2":0.98 -- 0.83 (8' Olhausen)
jtaylor996 -- 7':0.85 -- 5 1/8":0.88 -- 146deg:1.09 -- 1.51":1.00 -- 0.82 (7' Legacy home table)
dr_dave -- 8':0.90 -- 5":0.91 -- 1/2":0.98 -- 1 3/8":0.98 -- 0.79 (fictitious 8' example "A")
Mooneye -- 7':0.85 -- 4 7/8":0.91 -- 3/4":1.02 -- 1 5/8":1.00 -- 0.79 (7' Brunswick "Ranchero")
SloMoHolic -- 6':0.85 -- 4 1/2":1.00 -- 0":0.95 -- 5/8":0.95 -- 0.77 (old 6' Valley "bar box")
dzcues -- 7':0.85 -- 4 1/2":1.00 -- 0":0.95 -- 1/2":0.95 -- 0.77 (7' Valley "bar box")
dr_dave -- 7':0.85 -- 4 1/2":1.00 -- 0":0.95 -- 3/4":0.95 -- 0.77 (7' Valley/Dynamo "bar box" at West End, Fort Collins)

pocket said:

This is an unknown brand table, I'm told from the '80s. The gentleman I bought it from claimed he played at a pro level and had had the table designed to be particularly challenging to prepare him for tournaments.

He could no longer play due to health issues so he was selling his table (to allow his wife to reclaim their living room).

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That certainly is a tough table ... good for practice if you don't get too frustrated.

Thanks,
Dave

CoreyClark said:

Here's my table (GC I), using the spreadsheet it gave me a TDF of 1.02

9'
5" pocket
4" throat
2 1/8" shelf

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Thank you for posting (and for using the spreadsheet). I've added the following to the first post:

CoreyClark -- 9':1.00 -- 5":0.91 -- 1":1.07 -- 2 1//8":1.05 -- 1.02 (GC I)

Regards,
Dave

Isaac said:

I fixed it. The problem was with parsing of decimal imperial values. I assumed that when using imperial units people will specify "4 1/4" instead of 4.25. Now it should work fine either way.

However Cardigan Kid please verify your measurements, since 3.8 inches is "3 and 3.2 quarters of an inch", I doubt that your ruler has such scale

Cheers,
Isaac

Click to expand...

Isaac,

Thank you for your effort on this, but I think there are still errors.

For example, for the following recently-added table:

CoreyClark -- 9':1.00 -- 5":0.91 -- 1":1.07 -- 2 1//8":1.05 -- 1.02 (GC I)

The TDF spreadsheet calculates the correct numbers, but this is what your tool reports:

Table Size: 9 ft
Units: Inch
Pocket mouth size: 5
Pocket throat size: 4
Shelf depth: 2 1/8

Table Size Factor: 1.00
Pocket Size Factor: 0.88
Pocket Angle Factor: 1.07
Pocket Shelf Factor: 1.03
Table Difficulty Factor: 0.97

The PSF is wrong (0.88 vs. 0.91) and the PLF is wrong (1.03 vs. 1.05), based on the data in the tables in the TDF document.

Again, it might help to look at the formulas in the spreadsheet calculator (cells B13, D13, F13 and H13). FYI, I made a couple of improvements (and fixed a small error) with the spreadsheet, so be sure to use the new copy. Your tool formulas should agree with the spreadsheet formulas. Hopefully, that helps you find the errors.

After you find and fix the errors, please try out the tool on a few of the tables already listed to make sure your results agree with the published numbers. And again, please let us know when you think it is fixed so I can also test it out some, and so we can start using it with confidence.

Thank you again for your effort. Your tool (once it is working properly) is much better and easier to use than my spreadsheet.

Catch you later,
Dave