The Jacksonville Project

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Bob Jewett

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Nov 13, 1998, 3:00:00 AM11/13/98
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Some of you have asked for details of the high-speed video tests
that were recently started. I say "started" because many questions
from our original list remain. Here is some preliminary info:

The intrepid experimenters:

Mike Shamos -- Pittsburgh
Bob Jewett -- California
Jim Buss -- St. Louis (for the ACA)
Hans de Jager -- The Hague, Netherlands
Walt Harris -- Florida

The equipment:

The camera: Kodak Ektapro Hi-Spec Motion Analyzer (Model 1012)

Frame rate is 1000 to 12000 frames per second (FPS).

Black and white -- no color.

Image height decreases with faster rates so that at 12000 FPS the
image is 1/12 of the height of the screen, but the full width. A
nice feature at that rate is that the system displays 12 images at
a time as stacked up strips which allows easy comparison of
successive frames during 1 millisecond.

Digital (RAM) memory holds over one second of recording time, even
at the fastest frame rate.

Triggering is by manual push button after the event. This was
very easy to use with such a large image memory.

Images can be viewed immediately on a regular TV monitor and can
be stored to video tape (S-VHS was used for storage) at playback
rates of 1 to 960 FPS. (30 FPS is the fastest that will get all
frames onto video tape.) It is also possible to tape in
single-frame-step mode for those situations where long
measurements (e.g. ten seconds) are needed on each frame
during analysis.

The system automatically puts sequence numbers, date/time,
recording conditions, etc. on the playback for VHS recording.

If you want to rent one of these, it is $4000 for a two-week
minimum rental period with the needed lenses, lights, and VCR
as well as a brief on-site course by a Kodak technician.

Lights: two 1000-watt spot lights. Hot. Since the imager is
sensitive to infrared, this could be thought of as a feature.
Red balls appear to be white.

Table: a nine-foot Diamond with medium-old Simonis cloth (860?).

Cue-actuator: Iron Willie (the Clawson Cues machine) was used to
shoot many of the shots, but other shots were taken by the
intrepid experimenters. We were left alone with wrenches and
screwdrivers and Willie, and made some minor modifications as
needed.

Location: The tests were conducted at Clawson Cues in Jacksonville
Florida. It was agreed beforehand that there would be no
restriction on what we said about the tests we did except that we
should not mention any of Clawson's product plans that we might hear
of while we were there.

(For those of you hoping for the final word on squirt and whose cue
is better, you won't hear it from these tests. Fast video is not a
good test technique for measuring squirt, although it is turning out
to be a good way to understand the causes and possible partial
fixes.)

The Jaguars rule! So do Jacksonville property values. And Jimmy
Caras gives lessons there.

Dates: The Kodak guy set up the equipment on the afternoon of Monday,
Nov. 2, 1998, and Buss and Jewett did a few final tests the morning
of Sunday, Nov. 8, before driving to the airport.

Financing: by Shamos, Jewett, Buss (ACA), de Jager and Ron Shepard.

More in other postings soon.

Bob Jewett


Bob Jewett

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Nov 13, 1998, 3:00:00 AM11/13/98
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Bob Jewett (jew...@netcom.com) wrote: ... More in other postings soon.

Here is the list of questions that we started with. Some of them
do not really require video. Some that do didn't get answered.

Bob Jewett

---------------------------------------------------------
Jacksonville questions, Version 6. -- all changes combined

Questions that the experiments should answer (time permitting):

1. How long is the tip on the ball?

2. Is there more than one contact?

3. Does the tip slip on the ball, and if so, which way?
3a. Does the tip move while on the ball? (side, draw, follow)

4. How does the tip contact time change with power and spin?

5. Is the contact time different for draw/follow/side?

6. How does the hardness of the tip change the time?
(How does it relate, if at all, to the Mueller rating?)

7. What sort of tip is most efficient? (Most spin or speed)

8. Does any special stroke result in better "action"?

9. Is there more squirt on a slippery surface?

10. What sort of cue construction has the least squirt?
10b. Ferrule?
10c. Shaft taper?
10d. Shaft diameter?
10e. Cue length?

11. Which way does the shaft bend on spin shots?

12. Is there noticible compression other than in the tip?

13. How does the position and firmness of the bridge affect the hit?

13b. Is the mechanical bridge different?

14. What happens on close english shots? (Is there a foul?)
14a. How is a foul avoided on fouette draw shots?

15. Does anything special happen on masse shots?
15b. What happens with half masse, with follow/draw/side?
15c. Is there a foul on close masse shots?
15d. How does the shaft bend on masse shots?

16. For a constant tip offset, is there a constant spin/speed ratio
regardless of the speed of the hit?

17. How much penetration is there on ball-ball collisions?

18. What happens on double hits?

19. What happens on shots into frozen balls? (Also, multiple balls.)

20. What happens on miscues?

21. How does the tip radius affect spin and squirt?

21b. Does tip radius change the maximum spin?

22. Is there a better chalk?

23. What is the cushion compression like?

24. Does the cue ball jump with a level (as possible) stick?

25. What is the relation between tip offset and squirt?

26. What happens on the "inside draw by the rail shot"?

27. What are the details of frozen-ball combination throw shots?

28. What happens to the front ball in a frozen-ball combination?

29. Does the cue ball bounce back on a full follow shot?

30. How does speed affect the cushion rebound angle?

31. What parameters affect how much the cue ball jumps? (speed, angle)

32. How much spin can be transferred from cue ball to object ball?
32a. What is the best way to transfer the maximum?

33. Does draw or follow affect the angle at which an object ball is cut?

34. Does a large ball affect any of the results? Carom balls? Ivory?

35. What is angular velocity of a cue ball shot with maximum English?

36. What is the effect of dust, chalk, silicone, etc. on the balls?

37. What is the effect of cue speed on collision-induced throw?

38. What happens on shaft jumping? (Why does it work better?)

39. Does the slate bend measurably on a jump or masse shot?

40. What is the effect of cue speed on squirt?

41. How many ball-ball contacts are there on a kiss-back shot?

42. Does spin take more for a slowly moving ball?

43. What is the best way to run a frozen ball down the rail?

44. What happens in break shots? (8-ball, 9-ball, straight pool)

45. What is the essential difference between a masse and a jump shot?

46. Is there OB to OB english transfer?

47. What happens on the Hustler frozen bank?

48. How does added lead (on the ferrule) change the shot?

49. What happens on the impossible combo on rail?
[Described in RSB earlier, with the two balls frozen and 15mm apart
and the cue ball coming in full on one from 45 degrees.]

50. How does the Wimpy pinch work? (a trick shot that several players
demo now)

51. How does the "pocket hook force-through" work.


Canpacks

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Nov 13, 1998, 3:00:00 AM11/13/98
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> jew...@netcom.com (Bob Jewett)

>
> (For those of you hoping for the final word on squirt and whose cue
> is better, you won't hear it from these tests. Fast video is not a
> good test technique for measuring squirt, although it is turning out
> to be a good way to understand the causes and possible partial
> fixes.)

Mr. Jewett, Will copys of the tapes be for sale?> The Jaguars rule! So do


Jacksonville property values. And Jimmy
> Caras gives lessons there.

Compaired to so. Calf. values??????
Thanks D. Crosby

Stoney

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Nov 13, 1998, 3:00:00 AM11/13/98
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Bob Jewett wrote:
>
> Some of you have asked for details of the high-speed video tests <Snip>

> The intrepid experimenters:
>
> Mike Shamos -- Pittsburgh
> Bob Jewett -- California
> Jim Buss -- St. Louis (for the ACA)
> Hans de Jager -- The Hague, Netherlands
> Walt Harris -- Florida
>
<Snip>

> If you want to rent one of these, it is $4000 for a two-week
> minimum rental period with the needed lenses, lights, and VCR
> as well as a brief on-site course by a Kodak technician.
>

<Snip>


>
> Dates: The Kodak guy set up the equipment on the afternoon of Monday,
> Nov. 2, 1998, and Buss and Jewett did a few final tests the morning
> of Sunday, Nov. 8, before driving to the airport.
>
> Financing: by Shamos, Jewett, Buss (ACA), de Jager and Ron Shepard.
>

So, let me get this straight. The above GOF (Gang of Five)
out-of-pocketed all expenses involved in this experiment, other than
testing facilities? At least, that's the way I read this post.

If so, without reservation, I commend each and every one of them,
regardless of any profit motives they may or may not have. In the past
(and probably the future) I may not agree with them or like what they
have to say but they will have my respect for undertaking such a
venture. Members of the RSB community should be duely grateful for
whatever 'free' information comes of this and be willing to pay (if it
is in the budget) for whatever information is put on the open market.

Regards,
Stoney

jim...@neosoft.com

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Nov 13, 1998, 3:00:00 AM11/13/98
to

> > Financing: by Shamos, Jewett, Buss (ACA), de Jager and Ron Shepard.
> >
>
> So, let me get this straight. The above GOF (Gang of Five)
> out-of-pocketed all expenses involved in this experiment, other than
> testing facilities? At least, that's the way I read this post.
>
> If so, without reservation, I commend each and every one of them,
> regardless of any profit motives they may or may not have. In the past
> (and probably the future) I may not agree with them or like what they
> have to say but they will have my respect for undertaking such a
> venture. Members of the RSB community should be duely grateful for
> whatever 'free' information comes of this and be willing to pay (if it
> is in the budget) for whatever information is put on the open market.
>

> ==================================

That's right, There's no profit motive in any of this...It was done for the
pure research and understanding of the most facinating game we know..

A little more clarification. The group listed above used the camera for one
week. Predator is paying for half of the rental and is using the camera this
week for his own research. The understanding was that Predator let us do our
thing without interference or influence. He also agreed, as Bob Aluded to
that what ever we found out, we could publish, even if it turned out bad for
him, which it did not. The ACA's involvement was purely for the interest of
cues and cue reactions at high speed. The ACA paid $500.00 of the rental,
with the agreement that any data or information be made available to all
billiard publications on an equal footing, and that the project was for pure
research, not to try to prove who's cue was or was not the best.

--JIM BUSS--

-----------== Posted via Deja News, The Discussion Network ==----------
http://www.dejanews.com/ Search, Read, Discuss, or Start Your Own

emer...@execpc.com

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Nov 13, 1998, 3:00:00 AM11/13/98
to
In article <364C3A27...@tconl.com>,

Stoney <wst...@tconl.com> wrote:
> Bob Jewett wrote:
> >
> > Some of you have asked for details of the high-speed video tests <Snip>
> > The intrepid experimenters:
> >
> > Mike Shamos -- Pittsburgh
> > Bob Jewett -- California
> > Jim Buss -- St. Louis (for the ACA)
> > Hans de Jager -- The Hague, Netherlands
> > Walt Harris -- Florida
> >
> <Snip>
>
> > If you want to rent one of these, it is $4000 for a two-week
> > minimum rental period with the needed lenses, lights, and VCR
> > as well as a brief on-site course by a Kodak technician.
> >
> <Snip>
> >
> > Dates: The Kodak guy set up the equipment on the afternoon of Monday,
> > Nov. 2, 1998, and Buss and Jewett did a few final tests the morning
> > of Sunday, Nov. 8, before driving to the airport.
> >
> > Financing: by Shamos, Jewett, Buss (ACA), de Jager and Ron Shepard.
> >
>
> So, let me get this straight. The above GOF (Gang of Five)
> out-of-pocketed all expenses involved in this experiment, other than
> testing facilities? At least, that's the way I read this post.
>
> If so, without reservation, I commend each and every one of them,
> regardless of any profit motives they may or may not have. In the past
> (and probably the future) I may not agree with them or like what they
> have to say but they will have my respect for undertaking such a
> venture. Members of the RSB community should be duely grateful for
> whatever 'free' information comes of this and be willing to pay (if it
> is in the budget) for whatever information is put on the open market.
>
> Regards,
> Stoney
>

I agree 100%. I am very interested in seeing the results of these studies,
and possibly helping to interpret the test results. I will be happy to pay
for the costs of shipping, duplication, and other reasonable charges. I
would very likely be willing to participate financially and physically in
future studies, if necessary. Please contact me if interested.

Steven Hegg

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Nov 13, 1998, 3:00:00 AM11/13/98
to
I would like to join what I think will be a long list of positive responses
to this highly commendable effort. The fact that the participants invested
their own dollars in addition to their time and sweat, makes it all that
much better. I think there is little doubt that the final results will be
enlightening and I look forward to reading about them in RSB or another
forum.

However based on the information made public on RSB to this point (Bob's
project outline and list of questions), I did have a few of what I feel are
significant comments. I submit the comments not as an effort to rain on the
team's well-deserved parade, but as part of the quest for billiards
illumination.

- With respect to question 10, which asks what sort of cue construction has
the least squirt, the question can't really be answered completely based on
an analysis of only those 4 variables. I can think of at least 5 or 6
additional variables which are at least as significant as the four mentioned
in the original question.

- Similarly with question 21, which asks about a relationship tip radius and
spin and squirt, this question can't really be answered completely based on
an analysis of this single variable. As with question 10, there are several
other variables at play.

- Finally, there has been no mention so far of the use of any accelerometers
to measure the cue acceleration profile (and velocity and displacement
through numerical integration). I hope that at some point during the
proceedings, the team placed 1 or 2 multiple-axis accelerometers on the cue
to sense the cue's motion during the stroke and structural response while in
contact with the cue ball. In my own wrong opinion, these are essential
measurements in this sort of study.

Regardless of personal opinion, the team has my thanks and congratulations
for their effort and achievement and for what I'm sure will be very
interesting results.

Steve

---------------------------------------------


Bob Jewett wrote in message ...


>Bob Jewett (jew...@netcom.com) wrote: ... More in other postings soon.
>
>Here is the list of questions that we started with. Some of them
>do not really require video. Some that do didn't get answered.


lotsa snippage

Steven Hegg

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Nov 13, 1998, 3:00:00 AM11/13/98
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emer...@execpc.com wrote in message <72hpb5$eg4$1...@nnrp1.dejanews.com>...

>In article <364C3A27...@tconl.com>,
> Stoney <wst...@tconl.com> wrote:


snippage

>> Members of the RSB community should be duely grateful for
>> whatever 'free' information comes of this and be willing to pay (if it
>> is in the budget) for whatever information is put on the open market.
>>
>> Regards,
>> Stoney
>>
>
>I agree 100%. I am very interested in seeing the results of these studies,
>and possibly helping to interpret the test results. I will be happy to pay
>for the costs of shipping, duplication, and other reasonable charges. I
>would very likely be willing to participate financially and physically in
>future studies, if necessary. Please contact me if interested.

Well said by both. Same goes here.

Bob Jewett

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Nov 13, 1998, 3:00:00 AM11/13/98
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Stoney (wst...@tconl.com) wrote:

: So, let me get this straight. The above GOF (Gang of Five)


: out-of-pocketed all expenses involved in this experiment, other than
: testing facilities? At least, that's the way I read this post.

Well, not exactly. Clawson Cues is paying for half of the rental
because they are using the camera for the second week of the rental.
The listed "financiers" came up with the other $2000, plus each person
present arranged his own airfare and lodging expenses.

Bob Jewett


Bob Jewett

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Nov 13, 1998, 3:00:00 AM11/13/98
to
Steven Hegg (steve...@right.com) wrote:

: - With respect to question 10, which asks what sort of cue construction has


: the least squirt, the question can't really be answered completely based on
: an analysis of only those 4 variables. I can think of at least 5 or 6
: additional variables which are at least as significant as the four mentioned
: in the original question.

What are those variables?

: - Similarly with question 21, which asks about a relationship tip radius and


: spin and squirt, this question can't really be answered completely based on
: an analysis of this single variable. As with question 10, there are several
: other variables at play.

What are those variables?

: - Finally, there has been no mention so far of the use of any accelerometers


: to measure the cue acceleration profile (and velocity and displacement
: through numerical integration). I hope that at some point during the
: proceedings, the team placed 1 or 2 multiple-axis accelerometers on the cue
: to sense the cue's motion during the stroke and structural response while in
: contact with the cue ball. In my own wrong opinion, these are essential
: measurements in this sort of study.

Acceleration can be calculated from the second derivative of position
versus time. Position can be read directly from the video. An
accelerometer would have given useful additional information, probably
with better resolution, and the camera recorder is capable of
simultaneously recording signals from accelerometers. I'm not sure how
the data would be displayed, since we didn't get that option.

Bob Jewett


fred....@nypro.com

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Nov 13, 1998, 3:00:00 AM11/13/98
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In article <72ho9d$d9u$1...@nnrp1.dejanews.com>,
jim...@neosoft.com wrote:
>

> That's right, There's no profit motive in any of this...It was done for the
> pure research and understanding of the most facinating game we know..
>
> A little more clarification. The group listed above used the camera for one
> week. Predator is paying for half of the rental and is using the camera this
> week for his own research. The understanding was that Predator let us do our
> thing without interference or influence. He also agreed, as Bob Aluded to
> that what ever we found out, we could publish, even if it turned out bad for
> him, which it did not.

I've had my eye on this Predator for a while now. Are you implying that I
should go for it?


<snip the rest>


--
Regards,

Fred Agnir (wondering who 'Bob Aluded' is)

Hey JimboCT, this signature tagging is catching, and kinda fun too.

Steven Hegg

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Nov 13, 1998, 3:00:00 AM11/13/98
to
Bob Jewett wrote in message ...

snippage

>What are those variables?

For both questions:
- Relative hardness or softness of the tip
- Machining and construction of the ferrule/shaft tenon assembly (I can
think of at least 4 subfactors under this item).
- Base materials of the shaft (carbon fiber composite, metal, radially
spliced wood, solid maple, solid hardwood)
- Natural frequency of the fully assembled cue.
- Design, machining, construction and materials for the main joint assembly
(many subfactors here).
- Design, machining, construction and materials in the front (many
subfactors here).
- Design, machining, construction and mterials used in A-joint (or whether
or not one is even used) (many subfactors here).
- Trueness of the machining around the A-joint after it is assembled.


>Acceleration can be calculated from the second derivative of position
>versus time.

snippage

Forgive me if I'm wrong, but it sounds like you have misinterpreted where
I'm trying to go with this point.


Let me rephrase my point of why I feel accelerometers are crucial to this
type of experimentation.

- First, Marlowe hypothesized a few years back that the group velocity of
the shock wave in a cue is approximately equal to the speed of sound. Using
accelerometers physically mounted to the cue could provide sufficient data
to substantiate or disprove this hypothesis. Nailing down this single
parameter would add a lot of accuracy to other types of analysis.

- Second, accelerometers could be used to analyze reflection, transmission,
attentuation and dispersion of the shock wave at the various interfaces in
various cues. This data could be used to prove whether or not joint design,
materials, etc., is a relevant factor is cue design. Obviously there is a
ton of practical experience to hypothesize that it is, but there's no
empirical data to support one belief vs. another.

- Third, accelerometers could gather data which could be used to compute the
natural frequency, vibration modes and resonances of various cue designs.
These findings could be used to determine whether or not one design is
superior to another or if anything beyond generic cue design is meaningless.
Again there is obviously a ton of practical experience to hypothesize that
design and construction make a difference, but no empirical data.

- Fourth, accelerometers could be used to measure the acceleration profile
of a wide variety of strokes. Assuming that the stroke of the Iron Willie
robot could be modulated to produce different stroke accelerations, then a
lot of useful data could be acquired. There seem to be 2 schools of thought
when it comes to cue and cue ball impact. The first is that cue and cue ball
contact time is essentially fixed and instantaneous. The second is that tip
contact time can be varied with different stroke accelerations. Data from
various stroke acceleration profiles could provide some explanations.

If these sorts of things did not get done during the Jacksonville Project,
then perhaps they might be included in any follow-on work. I have a lot of
experience in these types of measurements and data analysis and would be
interested in getting involved. I'd also be willing to back it up with as
much time and dollars as I could make available.

And don't get me wrong, these sorts of measurements and analyses are not
trivial and not inexpensive. But they are do-able and in my own wrong
opinion, they would shed a huge amount of empirical illumination to the
various hypotheses and myths that circulate through the billiard world.

Once again, my hat's off to the Jacksonville Project team for financing and
going through with such a challenging effort. I look forward to seeing any
data that the team chooses to make public.

Steve

Bob Jewett

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Nov 13, 1998, 3:00:00 AM11/13/98
to
Bob Jewett (jew...@netcom.com) wrote:

: Location: The tests were conducted at Clawson Cues in Jacksonville

I'd like to take this opportunity to thank Clawson Cues for hosting
this project. It would have been tougher to get the money together for
a full rental by ourselves. At least as importantly, they were
excellent hosts, providing free access to the test area even when they
weren't there, samples of several different styles and brands of cues,
impromptu manufacturing of needed fixtures, free copier and phone use,
and the occasional free lunch. And if you ever need a helper to grab
United Airlines by the lapels and shake your misplaced cues out of their
baggage "handling" department, you can find her in Jacksonville.

Bob Jewett


Michael Johnson

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Nov 13, 1998, 3:00:00 AM11/13/98
to
sounds like a new denzel washington movie...


Smorgass Bored

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Nov 13, 1998, 3:00:00 AM11/13/98
to
Hey GOF (Gang Of Five),
Were any tests done using an laminated shaft such as the one on my Arnot
Attack Cue ?
Which,BTW,may be seen at www.arnotq.net and click on ' sold cues ' & see
page #2.... If you happen to stop by Arnot's site don't forget to sign
his guestbook.For every ten rsb registrants Joey will spot me an ball at
one pocket. <g>

Doug W.
~>*)))>< Big fish eat Little fish ><(((*<~




Carl Hatchell

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Nov 14, 1998, 3:00:00 AM11/14/98
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Jim,
Just curious, if Predator is paying for a week and
Clawson is paying for another week, where did RSB
fit in? Was there enough time to complete all the
tests you had planned?

Carl Hatchell
Hayward, Ca.

jim...@neosoft.com wrote in message <72ho9d$d9u$1...@nnrp1.dejanews.com>...


>
>
>> > Financing: by Shamos, Jewett, Buss (ACA), de Jager and Ron Shepard.
>> >
>>

>> So, let me get this straight. The above GOF (Gang of Five)
>> out-of-pocketed all expenses involved in this experiment, other than
>> testing facilities? At least, that's the way I read this post.
>>

>> If so, without reservation, I commend each and every one of them,
>> regardless of any profit motives they may or may not have. In the past
>> (and probably the future) I may not agree with them or like what they
>> have to say but they will have my respect for undertaking such a

>> venture. Members of the RSB community should be duely grateful for


>> whatever 'free' information comes of this and be willing to pay (if it
>> is in the budget) for whatever information is put on the open market.
>>

>> ==================================


>
>That's right, There's no profit motive in any of this...It was done for the
>pure research and understanding of the most facinating game we know..
>
>A little more clarification. The group listed above used the camera for one
>week. Predator is paying for half of the rental and is using the camera this
>week for his own research. The understanding was that Predator let us do our
>thing without interference or influence. He also agreed, as Bob Aluded to
>that what ever we found out, we could publish, even if it turned out bad for

>him, which it did not. The ACA's involvement was purely for the interest of
>cues and cue reactions at high speed. The ACA paid $500.00 of the rental,
>with the agreement that any data or information be made available to all
>billiard publications on an equal footing, and that the project was for pure
>research, not to try to prove who's cue was or was not the best.
>
>--JIM BUSS--
>

Bob Jewett

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Nov 14, 1998, 3:00:00 AM11/14/98
to
Carl Hatchell (Ha...@nospam.2xtreme.net) wrote:
: Just curious, if Predator is paying for a week and
: Clawson is paying for another week, ...

Predator is the brand name of a cue made by Clawson Cues.

Bob Jewett


Bob Jewett

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Nov 14, 1998, 3:00:00 AM11/14/98
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Smorgass Bored (Smorga...@webtv.net) wrote:

: Were any tests done using an laminated shaft such as the one on my
: Arnot Attack Cue ?

There was a shaft there that had parallel laminations, but it seemed to
be unremarkable, so not much was done with it.

Bob Jewett


Smorgass Bored

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Nov 14, 1998, 3:00:00 AM11/14/98
to
Thanks Bob. Unremarkable? What made the the shafts that you 'did things
with' REMARKABLE?

jew...@netcom.com (Bob Jewett) Re: The Jacksonville Project????

Smorgass Bored (Smorga...@webtv.net) wrote:
Were any tests done using an laminated shaft such as the one on my Arnot
Attack Cue ?

Bob answered:


There was a shaft there that had parallel laminations, but it seemed to
be unremarkable, so not much was done with it.
Bob Jewett

Doug W.

Bob Jewett

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Nov 14, 1998, 3:00:00 AM11/14/98
to
Smorgass Bored (Smorga...@webtv.net) wrote:

: Thanks Bob. Unremarkable? What made the the shafts that you 'did things
: with' REMARKABLE?

By remarkable, I mean unlike other shafts we had available. Among the
various kinds were long pro taper, carom taper, 10-section laminated,
no ferrule, masse, hard tip, soft tip, some kind of composite, and so
on. Since we were looking mostly for the various basic elements of tip,
ball and rail collisions, there was not a lot of time to study any one
type that seemed a lot like the others.

I don't know where the parallel-laminated stick came from. Someone
tested it briefly and declared it to be nothing special. I did not try
it myself. If I were to try it, I would measure the aim-and-pivot
point for shots "with" and "against" the laminations.

Bob Jewett


Roger Ballenger

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Nov 14, 1998, 3:00:00 AM11/14/98
to

Bob Jewett wrote in message ...
>snip<
>I don't know where the parallel-laminated stick came from.
>snip< shots "with" and "against" the laminations.
>snip<


I think it comes from the Bible: "Laminations of Ezekiel"

Hee, hee...

Roger

Bob Jewett

unread,
Nov 16, 1998, 3:00:00 AM11/16/98
to
Here are some of the main surprises we ran into during the testing.
The following is not meant to be a rigorous presentation, and you
may have a different interpretation of what was seen.

The "retrograde" spin mentioned at the end also applies to the present
thread asking about "best draw". The usual assumption is that you can
only get to "zero retrograde", but we found that you can do slightly
better than than if you are willing to hit within one or two mm of a
sure miscue. With "retrograde" draw, the top of the cue ball is moving
backwards relative to the table just after the ball leaves the tip.

Bob Jewett

--------------------------------------

Most miscues seem to generate the sharp sound by the ferrule or
shaft slapping the ball sideways.

On a hard shot, the ball sinks about 1.5cm into the rail.

There is no buckling as such (ferrule bending towards the ball)
but the front of the stick is seen to move parallel to itself,
which implies an s-curve shape in the stick at some point.

The stick side-ways resonance is about 40Hz (for mine).

The hop off the rail is often due to the ball being forced down
into the rail groove and hopping out.

The Hustler opening-scene bank shot is (nearly?) always a foul.

The cue stick slows down upon contact with the ball by about 50%,
but then rises to about 85% of its previous speed in two or three
centimeters (as the hand acts on it).

When held by Willie, the stick does not slow down on contact, probably
due to Willie's very firm grip/clamp. When we padded the grip with
bubble wrap, Willie showed slowing very similar to that with a human
grip.

The chalk cloud flies in both directions on spin shots -- towards and
away from the center of the ball.

Some extreme spin shots seem to hit the cue ball twice without a miscue.

Contact time increases on softer shots, for softer tips, and with more
eccentric hits, but these are not really surprises.

With extreme side spin, it is possible to get "retrograde" spin, in
which the opposite side of the ball moves backwards relative to the
table.


Bob Jewett

unread,
Nov 16, 1998, 3:00:00 AM11/16/98
to
I'm finally able to make copies of the two SVHS tapes we made of the
shots taken at Jacksonville. I plan to put the whole 250 or so
tape segments onto a single two hour+ tape. Available immediately
(or as soon as I put the tape in the machine) is:

-- VHS or SVHS tape of the very slightly edited results
-- copies of the original notes we took while taping, including
some preliminary analysis
-- some additional notes to help you understand the shots

Contact me directly for details on how to order. The proceeds from
the $30 charge ($35 for SVHS) goes to help defray the cost of the
rental equipment.

A warning: there is much that is repetitive on the raw tape. I plan to
eventually make a shorter, well-edited version that covers up some of
our inexperience with making such videos. By "slightly edited" above,
I mean removing such things as the 15 minutes of normal-speed setup
that we recorded by accident. This will allow the raw material to fit
on one maximum-length (2:40) SVHS tape, from which I'll make the copies.

Bob Jewett


LMoss18701

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Nov 16, 1998, 3:00:00 AM11/16/98
to
>>Subject: Re: The Jacksonville Project

>I plan to put the whole 250 or so
>tape segments onto a single two hour+ tape. Available immediately

BOB,
i want to order one. tell me where to send my check and for how much.
be sure and tell walt i was one of the first to order. he and i have regular
conversations.

linda moss

Jim Barr

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Nov 16, 1998, 3:00:00 AM11/16/98
to

Bob Jewett wrote in message ...
>
>When held by Willie, the stick does not slow down on contact, probably
>due to Willie's very firm grip/clamp. When we padded the grip with
>bubble wrap, Willie showed slowing very similar to that with a human
>grip.

Thanks for sharing this info. When the above test was done was there a
difference in squirt?

>
>Some extreme spin shots seem to hit the cue ball twice without a miscue.

You say it seems to hit twice on extreme spin shots. Could it be possible
that it happens on all shots with spin?

Jim Barr

Bob Jewett

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Nov 16, 1998, 3:00:00 AM11/16/98
to
Jim Barr (jim...@sound.net) wrote:

: Bob Jewett wrote in message ...
: > ... When we padded [Willie's] grip with


: > bubble wrap, Willie showed slowing very similar to that with a human
: > grip.

: Thanks for sharing this info. When the above test was done was there a
: difference in squirt?

We measured squirt only once briefly before the camera was ready.
High-speed video is not a useful tool to measure it, although it may
suggest some fixes or reasons.

: > Some extreme spin shots seem to hit the cue ball twice without a miscue.

: You say it seems to hit twice on extreme spin shots. Could it be
: possible that it happens on all shots with spin?

No. There are many spin shots on the tape where you can see the tip
approaching the ball, and the tip coming in contact with the ball, and
the tip compressing as the ball starts to move forward and spin, and
the tip and shaft start to move sideways, and the tip uncompresses and
then leaves the ball, never to return.

Bob Jewett

Ken Bour

unread,
Nov 18, 1998, 3:00:00 AM11/18/98
to
I don't plan on ordering the tape. I do not have the time, inclination, or
knowledge to evaluate the data and draw appropriate conclusions.

I would happily pay a reasonable fee to a qualified group that will study
the tape and the experimental data exhaustively and "net out" the
conclusions for the layman to understand -- including implications.

Ken Bour
Sterling, VA
http://www.erols.com/kbour

Bob Jewett wrote in message ...

>I'm finally able to make copies of the two SVHS tapes we made of the

>shots taken at Jacksonville. I plan to put the whole 250 or so


>tape segments onto a single two hour+ tape. Available immediately

Canpacks

unread,
Nov 20, 1998, 3:00:00 AM11/20/98
to
>I would happily pay a reasonable fee to a qualified group that will study
>the tape and the experimental data exhaustively and "net out" the
>conclusions for the layman to understand -- including implication

kEN Bour s words
I wish I hed somee spray paint marked impressed so I could spray myself...
D Crosby

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