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

dr_dave

Instructional Author
Gold Member
Silver Member
If we think of the hardest straight-in shot on the table (from one corner to an OB on the center spot to the opposite corner), we get a distance equal to the hypotenuse of the triangle made by the length of the sides. All other shots should be proportional to that shot. This is my first thought on size comparisons. However, shot difficulty is more closely related to the product of the two length (CB to OB and OB to pocket), so I squared my first numbers.

Did you refine your TSF after the post I quote above, how did you factor in 'crowding'?
The values and ranges for all of the factors were changed many times during the life of this thread, but they probably won't change going forward.

Remember, the TSF needs to characterize the full set of shots that comes up in typical play for a wide range of games and player skills. The factor should not be based strictly on the most difficult shot possible on each table.

FYI, factors from my previous post that were taken into consideration, along with input and feedback from many people in this thread and via e-mail, include:

All of the values and ranges for the individual TDF factors (TSF, PSF, PAF, PLF) were chosen very carefully based on how each factor affects the margin of error for a wide range of shots. In particular, the analyses and data in TP 3.4 - Margin of error based on distance and cut angle, TP 3.6 - Effective target sizes for slow shots into a corner pocket at different angles, and pocket "size" and "center" resource page were good starting points. However, adjustments were made based on anecdotal and empirical evidence for how tough a wide range of tables actual play. Many people provided input to guide these changes. Quite a few AZB users provided valuable input and feedback on the AZB TDF thread; and Mark Finkelstein, Mike Page, and Bob Jewett were particularly helpful in sharing their experience and judgement. Some of the factors that helped guide the adjustments include:

- On a smaller table, shot distances are generally shorter, and everything is easy to reach without a mechanical bridge; but on a larger table, there is less "traffic" with position play and balls are less likely to cluster.

- When the pockets are very small (and/or when the table is larger), further tightening has a much bigger effect since the precision required will be pushing the limits for even the best players. And for big pockets (and/or small table size), an increase might have very little effect for most shots where the precision required is well within the limits for even a mediocre player.

- For many shots, especially with a better player, a significant portion of the pocket margin is available for pocket cheating. In other words, many balls can be easily pocketed, and making the pocket smaller does more to limit pocket cheating than cause misses.

- For people who are not very accurate shot makers, both table size and pocket size make a huge difference, especially on bigger tables with "tighter" pockets. For accurate shot makers, a table size increase does not increase overall difficulty very much, especially if the pockets are not very "tight."

For more rationale and justification, see "Billiard University (BU) - Part IV: Table Difficulty" (BD, November, 2013).


Regards,
Dave
 

dr_dave

Instructional Author
Gold Member
Silver Member
My Gandy Winchester is 9', Mouth Size: 4 3/4" Throat Size: 4" Shelf Depth: 1 1/4"
Giving 0.92
Thank you for posting. Here's the latest:

Here's a mobile-friendly online tool (created by "Isaac") and an Excel spreadsheet for automatically calculating the TDF factors to determine the difficulty level of a table.

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_size:pSF -- mouth-throat_difference:pAF -- shelf_depth:pLF -- 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)
Marc Vidal -- 9':1.00 -- 4 1/8":1.15 -- 7/16":1.05 -- 1":0.98 -- 1.18 (shimmed Brunswick Tournament Edition)
chevybob20 -- 9':1.00 -- 4 1/8":1.15 -- 7/8":1.05 -- 1":0.98 -- 1.18 (Mark-Gregory-modified Centennial)
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)
Mikjary -- 9'-1.00 -- ??:1.15 -- ??:1.00 -- ??:0.98 -- 1.13 (Brunswick Centurion)
Ralph Kramden -- 9':1.0 -- 4 5/16":1.05 -- 1":1.07 -- 1 3/4":1.00 -- 1.12 (1962 Nine foot Gold Crown 1)
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")
MahnaMahna -- 10':1.10 -- 5 1/2":0.85 -- 2":1.09 -- 2 1/2": 1.07 -- 1.09 (snooker table poorly converted into a pool table)
Cardigan Kid -- 9':1.00 -- 4 1/4":1.10 -- 0.45":0.99 -- 1 5/16":0.99 -- 1.08 (GC II)
MSchaffer -- 9':1.00 -- 4 7/16:1.00 -- 15/16":1.07 -- 1 5/8":1.00 -- 1.07 (GCII, RKC mod)
cigardave -- 9':1.00 -- 4 1/2":1.00 -- 1":1.07 -- 1 3/4":1.00 -- 1.07 (typical Pro-Cut Diamond)
Side Pocket -- 10':1.10 -- 4 7/8":0.91 -- 1":1.07 -- 1 1/2":0.98 -- 1.05 (10' 1920-1925 Brunswick)
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)
CoreyClark -- 9':1.00 -- 5":0.91 -- 1":1.07 -- 2 1//8":1.05 -- 1.02 (GC I)
"standard" table -- 9':1.00 -- 4 7/16":1.00 -- 9/16":1.00 -- 1 5/8":1.00 -- 1.00 (average-difficulty table)
Goldball -- 8':0.90 -- 12.2cm:0.91 -- 4cm:1.14 -- 5.4cm:1.07 -- 1.00 (Heiron & Smith)
dr_dave -- 9':1.00 -- 5": 0.91 -- 1 1/8":1.10 -- 1 3/8":0.99 -- 0.99 (old GC II at MatchUps, Fort Collins)
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)
freds -- 8'+: 0.95 -- 4.9":0.91 -- 1.1":1.1 -- 1.8" 1.03 -- 0.98 (Gandy Big G, oversized 8)
Cardigan Kid -- 9':1.00 -- 4 1/2":1.00 -- 3/4":1.02 -- 1 1/16":0.95 -- 0.97 (GC III Table 7 at Premium Billiards, Syracuse, Mark Gregory-modified w/ Artemis cushions)
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)
Poolmanis -- 9':1.00 -- 10.9cm:1.05 -- 1cm:0.97 -- 3.1cm:0.95 -- 0.97 (modified SAM)
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)
Corwyn_8 -- 9':1.00 -- 4 3/4":0.95 -- 1 3/4":1.02 -- 1 1/4":0.95 -- 0.92 (Gandy Winchester)
beetle -- 9':1.00 -- 13.1cm:0.88 -- 2.2cm:1.03 -- 4.3cm:1.00 -- 0.91 (Olhausen York)
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)
buckshotshoey -- 8':0.90 -- 4 3/4":0.95 -- 3/4":1.02 -- 1 1/2":0.98 -- 0.85 (American Heritage "Independence")
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 "bar box" at West End, Fort Collins)
 

Mikjary

AzB Silver Member
Silver Member
Hey Dave,

Here are my measurements...

TSF- 9'
PSF- 4"
PAF- 9/16"
PLF- 1 5/16"

Thanks!

Best,
Mike
 

dr_dave

Instructional Author
Gold Member
Silver Member
Hey Dave,

Here are my measurements...

TSF- 9'
PSF- 4"
PAF- 9/16"
PLF- 1 5/16"

Thanks!

Best,
Mike
Thank you. I've added the measurements to the list. Here's the latest:

Here's a mobile-friendly online tool (created by "Isaac") and an Excel spreadsheet for automatically calculating the TDF factors to determine the difficulty level of a table.

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_size:pSF -- mouth-throat_difference:pAF -- shelf_depth:pLF -- 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)
Marc Vidal -- 9':1.00 -- 4 1/8":1.15 -- 7/16":1.05 -- 1":0.98 -- 1.18 (shimmed Brunswick Tournament Edition)
chevybob20 -- 9':1.00 -- 4 1/8":1.15 -- 7/8":1.05 -- 1":0.98 -- 1.18 (Mark-Gregory-modified Centennial)
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)
Mikjary -- 9'-1.00 -- 4":1.15 -- 9/16":1.00 -- 1 5/16":0.98 -- 1.13 (Brunswick Centurion)
Ralph Kramden -- 9':1.0 -- 4 5/16":1.05 -- 1":1.07 -- 1 3/4":1.00 -- 1.12 (1962 Nine foot Gold Crown 1)
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")
MahnaMahna -- 10':1.10 -- 5 1/2":0.85 -- 2":1.09 -- 2 1/2": 1.07 -- 1.09 (snooker table poorly converted into a pool table)
Cardigan Kid -- 9':1.00 -- 4 1/4":1.10 -- 0.45":0.99 -- 1 5/16":0.99 -- 1.08 (GC II)
MSchaffer -- 9':1.00 -- 4 7/16:1.00 -- 15/16":1.07 -- 1 5/8":1.00 -- 1.07 (GCII, RKC mod)
cigardave -- 9':1.00 -- 4 1/2":1.00 -- 1":1.07 -- 1 3/4":1.00 -- 1.07 (typical Pro-Cut Diamond)
Side Pocket -- 10':1.10 -- 4 7/8":0.91 -- 1":1.07 -- 1 1/2":0.98 -- 1.05 (10' 1920-1925 Brunswick)
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)
CoreyClark -- 9':1.00 -- 5":0.91 -- 1":1.07 -- 2 1//8":1.05 -- 1.02 (GC I)
"standard" table -- 9':1.00 -- 4 7/16":1.00 -- 9/16":1.00 -- 1 5/8":1.00 -- 1.00 (average-difficulty table)
Goldball -- 8':0.90 -- 12.2cm:0.91 -- 4cm:1.14 -- 5.4cm:1.07 -- 1.00 (Heiron & Smith)
dr_dave -- 9':1.00 -- 5": 0.91 -- 1 1/8":1.10 -- 1 3/8":0.99 -- 0.99 (old GC II at MatchUps, Fort Collins)
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)
freds -- 8'+: 0.95 -- 4.9":0.91 -- 1.1":1.1 -- 1.8" 1.03 -- 0.98 (Gandy Big G, oversized 8)
Cardigan Kid -- 9':1.00 -- 4 1/2":1.00 -- 3/4":1.02 -- 1 1/16":0.95 -- 0.97 (GC III Table 7 at Premium Billiards, Syracuse, Mark Gregory-modified w/ Artemis cushions)
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)
Poolmanis -- 9':1.00 -- 10.9cm:1.05 -- 1cm:0.97 -- 3.1cm:0.95 -- 0.97 (modified SAM)
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)
Corwyn_8 -- 9':1.00 -- 4 3/4":0.95 -- 1 3/4":1.02 -- 1 1/4":0.95 -- 0.92 (Gandy Winchester)
beetle -- 9':1.00 -- 13.1cm:0.88 -- 2.2cm:1.03 -- 4.3cm:1.00 -- 0.91 (Olhausen York)
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)
buckshotshoey -- 8':0.90 -- 4 3/4":0.95 -- 3/4":1.02 -- 1 1/2":0.98 -- 0.85 (American Heritage "Independence")
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 "bar box" at West End, Fort Collins)
 

wigglybridge

14.1 straight pool!
Silver Member
Hi Dave,

and Thank You for compiling and analyzing this data!

wigglybridge: GC 1.5, rails rebuilt & cushions replaced by Jay Spielberg
tsf: 9'
psf: 4.5
throat: 4 & 1/8
shelf: 1.5
 

dr_dave

Instructional Author
Gold Member
Silver Member
Hi Dave,

and Thank You for compiling and analyzing this data!

wigglybridge: GC 1.5, rails rebuilt & cushions replaced by Jay Spielberg
tsf: 9'
psf: 4.5
throat: 4 & 1/8
shelf: 1.5
You're welcome ... and thank you for posting.

Regards,
Dave
 

dr_dave

Instructional Author
Gold Member
Silver Member
Here's the latest:
----------------------

Here's a mobile-friendly online tool (created by "Isaac") and an Excel spreadsheet for automatically calculating the TDF factors to determine the difficulty level of a table.

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_size:pSF -- mouth-throat_difference:pAF -- shelf_depth:pLF -- 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)
Marc Vidal -- 9':1.00 -- 4 1/8":1.15 -- 7/16":1.05 -- 1":0.98 -- 1.18 (shimmed Brunswick Tournament Edition)
chevybob20 -- 9':1.00 -- 4 1/8":1.15 -- 7/8":1.05 -- 1":0.98 -- 1.18 (Mark-Gregory-modified Centennial)
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)
Mikjary -- 9'-1.00 -- 4":1.15 -- 9/16":1.00 -- 1 5/16":0.98 -- 1.13 (Brunswick Centurion)
Ralph Kramden -- 9':1.0 -- 4 5/16":1.05 -- 1":1.07 -- 1 3/4":1.00 -- 1.12 (1962 Nine foot Gold Crown 1)
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")
MahnaMahna -- 10':1.10 -- 5 1/2":0.85 -- 2":1.09 -- 2 1/2": 1.07 -- 1.09 (snooker table poorly converted into a pool table)
Cardigan Kid -- 9':1.00 -- 4 1/4":1.10 -- 0.45":0.99 -- 1 5/16":0.99 -- 1.08 (GC II)
MSchaffer -- 9':1.00 -- 4 7/16:1.00 -- 15/16":1.07 -- 1 5/8":1.00 -- 1.07 (GCII, RKC mod)
cigardave -- 9':1.00 -- 4 1/2":1.00 -- 1":1.07 -- 1 3/4":1.00 -- 1.07 (typical Pro-Cut Diamond)
Side Pocket -- 10':1.10 -- 4 7/8":0.91 -- 1":1.07 -- 1 1/2":0.98 -- 1.05 (10' 1920-1925 Brunswick)
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)
CoreyClark -- 9':1.00 -- 5":0.91 -- 1":1.07 -- 2 1//8":1.05 -- 1.02 (GC I)
"standard" table -- 9':1.00 -- 4 7/16":1.00 -- 9/16":1.00 -- 1 5/8":1.00 -- 1.00 (average-difficulty table)
Goldball -- 8':0.90 -- 12.2cm:0.91 -- 4cm:1.14 -- 5.4cm:1.07 -- 1.00 (Heiron & Smith)
dr_dave -- 9':1.00 -- 5": 0.91 -- 1 1/8":1.10 -- 1 3/8":0.99 -- 0.99 (old GC II at MatchUps, Fort Collins)
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)
freds -- 8'+: 0.95 -- 4.9":0.91 -- 1.1":1.1 -- 1.8" 1.03 -- 0.98 (Gandy Big G, oversized 8)
Cardigan Kid -- 9':1.00 -- 4 1/2":1.00 -- 3/4":1.02 -- 1 1/16":0.95 -- 0.97 (GC III Table 7 at Premium Billiards, Syracuse, Mark Gregory-modified w/ Artemis cushions)
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)
Poolmanis -- 9':1.00 -- 10.9cm:1.05 -- 1cm:0.97 -- 3.1cm:0.95 -- 0.97 (modified SAM)
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)
wigglybridge -- 9':1.00 -- 4 1/2":1.00 -- 3/8":0.97 -- 1 1/2": 0.98 -- 0.95 (GC 1.5, rails rebuilt & cushions replaced by Jay Spielberg)
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)
Corwyn_8 -- 9':1.00 -- 4 3/4":0.95 -- 1 3/4":1.02 -- 1 1/4":0.95 -- 0.92 (Gandy Winchester)
beetle -- 9':1.00 -- 13.1cm:0.88 -- 2.2cm:1.03 -- 4.3cm:1.00 -- 0.91 (Olhausen York)
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)
buckshotshoey -- 8':0.90 -- 4 3/4":0.95 -- 3/4":1.02 -- 1 1/2":0.98 -- 0.85 (American Heritage "Independence")
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 "bar box" at West End, Fort Collins)
 

wigglybridge

14.1 straight pool!
Silver Member
ooops. went back and looked at the chart and text more carefully, realized i measured the throat size at the wrong place. so my numbers should be:

wigglybridge: GC 1.5, rails rebuilt & cushions replaced by Jay Spielberg
tsf: 9'
psf: 4.5
throat: 3 & 7/8
shelf: 1.5
 

dr_dave

Instructional Author
Gold Member
Silver Member
ooops. went back and looked at the chart and text more carefully, realized i measured the throat size at the wrong place. so my numbers should be:

wigglybridge: GC 1.5, rails rebuilt & cushions replaced by Jay Spielberg
tsf: 9'
psf: 4.5
throat: 3 & 7/8
shelf: 1.5
Thank you for the update. I'll make the correction.

Regards,
Dave
 

dr_dave

Instructional Author
Gold Member
Silver Member
Here's the latest:

Here's a mobile-friendly online tool (created by "Isaac") and an Excel spreadsheet for automatically calculating the TDF factors to determine the difficulty level of a table.

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_size:pSF -- mouth-throat_difference:pAF -- shelf_depth:pLF -- 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)
Marc Vidal -- 9':1.00 -- 4 1/8":1.15 -- 7/16":1.05 -- 1":0.98 -- 1.18 (shimmed Brunswick Tournament Edition)
chevybob20 -- 9':1.00 -- 4 1/8":1.15 -- 7/8":1.05 -- 1":0.98 -- 1.18 (Mark-Gregory-modified Centennial)
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)
Mikjary -- 9'-1.00 -- 4":1.15 -- 9/16":1.00 -- 1 5/16":0.98 -- 1.13 (Brunswick Centurion)
Ralph Kramden -- 9':1.0 -- 4 5/16":1.05 -- 1":1.07 -- 1 3/4":1.00 -- 1.12 (1962 Nine foot Gold Crown 1)
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")
MahnaMahna -- 10':1.10 -- 5 1/2":0.85 -- 2":1.09 -- 2 1/2": 1.07 -- 1.09 (snooker table poorly converted into a pool table)
Cardigan Kid -- 9':1.00 -- 4 1/4":1.10 -- 0.45":0.99 -- 1 5/16":0.99 -- 1.08 (GC II)
MSchaffer -- 9':1.00 -- 4 7/16:1.00 -- 15/16":1.07 -- 1 5/8":1.00 -- 1.07 (GCII, RKC mod)
cigardave -- 9':1.00 -- 4 1/2":1.00 -- 1":1.07 -- 1 3/4":1.00 -- 1.07 (typical Pro-Cut Diamond)
Side Pocket -- 10':1.10 -- 4 7/8":0.91 -- 1":1.07 -- 1 1/2":0.98 -- 1.05 (10' 1920-1925 Brunswick)
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)
CoreyClark -- 9':1.00 -- 5":0.91 -- 1":1.07 -- 2 1//8":1.05 -- 1.02 (GC I)
"standard" table -- 9':1.00 -- 4 7/16":1.00 -- 9/16":1.00 -- 1 5/8":1.00 -- 1.00 (average-difficulty table)
Goldball -- 8':0.90 -- 12.2cm:0.91 -- 4cm:1.14 -- 5.4cm:1.07 -- 1.00 (Heiron & Smith)
dr_dave -- 9':1.00 -- 5": 0.91 -- 1 1/8":1.10 -- 1 3/8":0.99 -- 0.99 (old GC II at MatchUps, Fort Collins)
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)
freds -- 8'+: 0.95 -- 4.9":0.91 -- 1.1":1.1 -- 1.8" 1.03 -- 0.98 (Gandy Big G, oversized 8)
Cardigan Kid -- 9':1.00 -- 4 1/2":1.00 -- 3/4":1.02 -- 1 1/16":0.95 -- 0.97 (GC III Table 7 at Premium Billiards, Syracuse, Mark Gregory-modified w/ Artemis cushions)
wigglybridge -- 9':1.00 -- 4 1/2":1.00 -- 5/8":1.00 -- 1 1/2": 0.98 -- 0.98 (GC 1.5, rails rebuilt & cushions replaced by Jay Spielberg)
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)
Poolmanis -- 9':1.00 -- 10.9cm:1.05 -- 1cm:0.97 -- 3.1cm:0.95 -- 0.97 (modified SAM)
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)
Corwyn_8 -- 9':1.00 -- 4 3/4":0.95 -- 1 3/4":1.02 -- 1 1/4":0.95 -- 0.92 (Gandy Winchester)
beetle -- 9':1.00 -- 13.1cm:0.88 -- 2.2cm:1.03 -- 4.3cm:1.00 -- 0.91 (Olhausen York)
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)
buckshotshoey -- 8':0.90 -- 4 3/4":0.95 -- 3/4":1.02 -- 1 1/2":0.98 -- 0.85 (American Heritage "Independence")
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 "bar box" at West End, Fort Collins)
 

wigglybridge

14.1 straight pool!
Silver Member
so, here's a thing i don't understand:

when my table was first installed, the pockets were at 4&3/8, and after 2 days, i texted Jay and said it was just too tight to play 14.1 (for me, anyway, and we've had discussions about this on the 14.1 forum and it's almost unanimous that you can't play proper straight pool at less than 4.5", with most people settling around 4.75 as "good"). so Jay opened the pockets up by replacing the 3/16" Diamond neoprene facings he'd used with 1/8" Brunswick facings, giving me 4.5" pockets, which i thought would be tough but manageable.

again, i play 14.1, so relative table difficulty is both obvious and measureable: how many balls do you run?

the thing is, my runs immediately Plummeted after the change to wider pockets -- cut in half or more.

is it the angles? i would think that replacing a planar object with another planar object of a different thickness wouldn't change that. is the stiffer facing material? either way, i now rattle balls at an alarming rate, and i am certainly not hitting them unnecessarily hard.

and while i almost never get to play on a Diamond with pro-cut pockets, and haven't for a few years, my memory of that is that this table is playing Much tighter.

whatever it is, it's not a subtle effect.
 
Last edited:

dr_dave

Instructional Author
Gold Member
Silver Member
so, here's a thing i don't understand:

when my table was first installed, the pockets were at 4&3/8, and after 2 days, i texted Jay and said it was just too tight to play 14.1 (for me, anyway, and we've had discussions about this on the 14.1 forum and it's almost unanimous that you can't play proper straight pool at less than 4.5", with most people settling around 4.75 as "good"). so Jay opened the pockets up by replacing the 3/16" Diamond neoprene facings he'd used with 1/8" Brunswick facings, giving me 4.5" pockets, which i thought would be tough but manageable.

again, i play 14.1, so relative table difficulty is both obvious and measureable: how many balls do you run?

the thing is, my runs immediately Plummeted after the change to wider pockets -- cut in half or more.

is it the angles? i would think that replacing a planar object with another planar object of a different thickness wouldn't change that. is the stiffer facing material? either way, i now rattle balls at an alarming rate, and i am certainly not hitting them unnecessarily hard.

and while i almost never get to play on a Diamond with pro-cut pockets, and haven't for a few years, my memory of that is that this table is playing Much tighter.

whatever it is, it's not a subtle effect.
Obviously, if the angles of the pocket facings are the same and the pockets are bigger (and everything else is the same), the pockets should play easier. The facing material can definitely make a difference. The condition of the cloth on the facing (slickness, cleanliness, and tightness) can also make a big difference. Humidity can also have a big effect. Based on what you wrote, I would think the facing material is the most-likely culprit.

Catch you later,
Dave
 

Poolmanis

AzB Silver Member
Silver Member
I believe pocket cut angle is more crucial than this table difficulty chart says...
My table is near 11cm point to point. And deep pocket is 10 cm and one pro player said he plays 10 cm(4 inch) pocket cut straight any before my table pocket cut. Rebound angle from pocket cut is so sick...
 

Cardigan Kid

AzB Silver Member
Silver Member
so, here's a thing i don't understand:

when my table was first installed, the pockets were at 4&3/8, and after 2 days, i texted Jay and said it was just too tight to play 14.1 (for me, anyway, and we've had discussions about this on the 14.1 forum and it's almost unanimous that you can't play proper straight pool at less than 4.5", with most people settling around 4.75 as "good"). so Jay opened the pockets up by replacing the 3/16" Diamond neoprene facings he'd used with 1/8" Brunswick facings, giving me 4.5" pockets, which i thought would be tough but manageable.

again, i play 14.1, so relative table difficulty is both obvious and measureable: how many balls do you run?

the thing is, my runs immediately Plummeted after the change to wider pockets -- cut in half or more.

is it the angles? i would think that replacing a planar object with another planar object of a different thickness wouldn't change that. is the stiffer facing material? either way, i now rattle balls at an alarming rate, and i am certainly not hitting them unnecessarily hard.

and while i almost never get to play on a Diamond with pro-cut pockets, and haven't for a few years, my memory of that is that this table is playing Much tighter.

whatever it is, it's not a subtle effect.

It was my understanding that if the pocket is widened, then the down angle of the facings has to be corrected as well. The down angle of the facing can make the pocket accept anything hit at it and also rattle anything hit the same way.

Maybe this is more for the table mechanic forum, but there has been many debates and information passed had been robust in regards to getting sub rails extended and facing correct down angle when adjusting pockets to a desired width.
 

Ralph Kramden

BOOM!.. ZOOM!.. MOON!
Silver Member
I believe pocket cut angle is more crucial than this table difficulty chart says...
My table is near 11cm point to point. And deep pocket is 10 cm and one pro player said he plays 10 cm(4 inch) pocket cut straight any before my table pocket cut. Rebound angle from pocket cut is so sick...

IMO.. shelf depth is also a major factor with pocket angles. If a pocket angle deflects the ball towards
the opposite angle, it can hang on the shelf with slow rolling shots, or it rattles with harder shots. If the
pocket angle is about 141 degrees or less, the shelf depth isn't as critical. The ball deflects toward the
back of the pocket on all shots. Facing material, pocketing down angles and shelf depth all play a part.

This sums it up: Tables with 143+ degree pocket angles and over 1 1/2" shelf depths, just play tougher.

.
 
Last edited:

dr_dave

Instructional Author
Gold Member
Silver Member
FYI, Ricky Sy on Facebook just sent me measurements for the tough money table at Hard Times in Bellflower, CA. Here's the data:

Ricky Sy -- 9':1.00 -- 3 3/4":1.31 -- 1/4":0.97 -- 5/8":0.98 -- 1.25 (money table at Hard Times in Bellflower, CA)

Those are some tough pockets!

Regards,
Dave
 

dr_dave

Instructional Author
Gold Member
Silver Member
Latest update:

Here's a mobile-friendly online tool (created by "Isaac") and an Excel spreadsheet for automatically calculating the TDF factors to determine the difficulty level of a table.

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_size:pSF -- mouth-throat_difference:pAF -- shelf_depth:pLF -- 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")
Ricky Sy -- 9':1.00 -- 3 3/4":1.31 -- 1/4":0.97 -- 5/8":0.98 -- 1.25 (money table at Hard Times in Bellflower, CA)
Bonus Ball -- 9':1.00 -- 3 7/8":1.25 -- 1/8":0.97 -- 3/4":0.98 -- 1.19 (Bonus Ball table)
Marc Vidal -- 9':1.00 -- 4 1/8":1.15 -- 7/16":1.05 -- 1":0.98 -- 1.18 (shimmed Brunswick Tournament Edition)
chevybob20 -- 9':1.00 -- 4 1/8":1.15 -- 7/8":1.05 -- 1":0.98 -- 1.18 (Mark-Gregory-modified Centennial)
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)
Mikjary -- 9'-1.00 -- 4":1.15 -- 9/16":1.00 -- 1 5/16":0.98 -- 1.13 (Brunswick Centurion)
Ralph Kramden -- 9':1.0 -- 4 5/16":1.05 -- 1":1.07 -- 1 3/4":1.00 -- 1.12 (1962 Nine foot Gold Crown 1)
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")
MahnaMahna -- 10':1.10 -- 5 1/2":0.85 -- 2":1.09 -- 2 1/2": 1.07 -- 1.09 (snooker table poorly converted into a pool table)
Cardigan Kid -- 9':1.00 -- 4 1/4":1.10 -- 0.45":0.99 -- 1 5/16":0.99 -- 1.08 (GC II)
MSchaffer -- 9':1.00 -- 4 7/16:1.00 -- 15/16":1.07 -- 1 5/8":1.00 -- 1.07 (GCII, RKC mod)
cigardave -- 9':1.00 -- 4 1/2":1.00 -- 1":1.07 -- 1 3/4":1.00 -- 1.07 (typical Pro-Cut Diamond)
Side Pocket -- 10':1.10 -- 4 7/8":0.91 -- 1":1.07 -- 1 1/2":0.98 -- 1.05 (10' 1920-1925 Brunswick)
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)
CoreyClark -- 9':1.00 -- 5":0.91 -- 1":1.07 -- 2 1//8":1.05 -- 1.02 (GC I)
"standard" table -- 9':1.00 -- 4 7/16":1.00 -- 9/16":1.00 -- 1 5/8":1.00 -- 1.00 (average-difficulty table)
Goldball -- 8':0.90 -- 12.2cm:0.91 -- 4cm:1.14 -- 5.4cm:1.07 -- 1.00 (Heiron & Smith)
dr_dave -- 9':1.00 -- 5": 0.91 -- 1 1/8":1.10 -- 1 3/8":0.99 -- 0.99 (old GC II at MatchUps, Fort Collins)
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)
freds -- 8'+: 0.95 -- 4.9":0.91 -- 1.1":1.1 -- 1.8" 1.03 -- 0.98 (Gandy Big G, oversized 8)
Cardigan Kid -- 9':1.00 -- 4 1/2":1.00 -- 3/4":1.02 -- 1 1/16":0.95 -- 0.97 (GC III Table 7 at Premium Billiards, Syracuse, Mark Gregory-modified w/ Artemis cushions)
wigglybridge -- 9':1.00 -- 4 1/2":1.00 -- 5/8":1.00 -- 1 1/2": 0.98 -- 0.98 (GC 1.5, rails rebuilt & cushions replaced by Jay Spielberg)
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)
Poolmanis -- 9':1.00 -- 10.9cm:1.05 -- 1cm:0.97 -- 3.1cm:0.95 -- 0.97 (modified SAM)
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)
Corwyn_8 -- 9':1.00 -- 4 3/4":0.95 -- 1 3/4":1.02 -- 1 1/4":0.95 -- 0.92 (Gandy Winchester)
beetle -- 9':1.00 -- 13.1cm:0.88 -- 2.2cm:1.03 -- 4.3cm:1.00 -- 0.91 (Olhausen York)
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)
buckshotshoey -- 8':0.90 -- 4 3/4":0.95 -- 3/4":1.02 -- 1 1/2":0.98 -- 0.85 (American Heritage "Independence")
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 "bar box" at West End, Fort Collins)
 

dr_dave

Instructional Author
Gold Member
Silver Member
Has anybody played on the tough money tables at both Pool Sharks in Las Vegas and Hard Times in Bellflower? I am curious to know how people think they compare in relation to the TDF numbers reported.

Thanks,
Dave
 

fd_colorado

Go Pack Go!!!
Silver Member
Please bear with me, as I am neither an engineer nor a physicist. I also admit to not having read the 600-plus posts in this thread.

Trying to extrapolate anything more than relative pocket "toughness" is futile.

For example: Trying to assign a different value for Mosconi's high run number for any given table in the list not only would be futile, but you would find yourself endlessly weighting variables, with no way of checking your results.

Which leads me to a possible solution with a much smaller weighted variable set and greater precision: Go digital. In other words, say you have a video of Mosconi's run and then each shot is digitally mapped (your consistent source), you would then be able to repeat the run with a different TDF overlay.
 
Last edited:

dr_dave

Instructional Author
Gold Member
Silver Member
Please bear with me, as I am neither an engineer nor a physicist. I also admit to not having read the 600-plus posts in this thread.

Trying to extrapolate anything more than relative pocket "toughness" is futile.

For example: Trying to assign a different value for Mosconi's high run number for any given table in the list not only would be futile, but you would find yourself endlessly weighting variables, with no way of checking your results.

Which leads me to a possible solution with a much smaller weighted variable set and greater precision: Go digital. In other words, say you have a video of Mosconi's run and then each shot is digitally mapped (your consistent source), you would then be able to repeat the run with a different TDF overlay.
The best way to determine the TDF factor value ranges would be to use the BU Playing-Ability Exams to test many players over a wide range of ability on many different tables. The scores would be good indicators of table difficulty, assuming multiple trials are done on each table.

Unfortunately, we didn't have access to such a large set of useful data. Therefore, we did our best to choose the factor ranges based on input from many experienced people. Some analysis was also done to help. FYI, much of the rationale used is setting the values and ranges can be found on the table difficulty factor (TDF) resource page.

If you are really interested, check it out.

Regards,
Dave
 
Top