Good evening Mo,
Since it is my 1st post, I would like to start off by saying thank you for devoting your own time answering so many questions.
Having just been through the ibpsia phase 1 training, there are a few holes in my understanding regarding ball dynamics which I am trying to fill, and I believe you may be the only person who could answer my queries.
Some may be trivial, others may be insane, and obviously many may be irrelevant so here goes.
a) Which axis does a drilled bowling ball migrate to ?
According to this:
[youtube][/youtube]
it appears to be the psa. However according to the usbc motion study, only the high diff test ball you provided manages to migrate to a lower rg axis, i.e. closer to the pin.
b) What effect does drilling the ball have on the 60 deg spin time of a ball ?
i.e. if bowling ball X takes 7 seconds to reach it's preferred spin axis, how much does this change when the ball is drilled, and how is this affected by the layout?
c) I we were to swap the primary and secondary pins, which way would the ball flare, and what kind of motion would we expect ?
i.e. with psa near the fingers, pin near the thumb. (skip the balance hole part)
d) How much affect does drilling deep finger holes close to the pin have to reaction, compared to the effect of the layout and the effect of the balance hole ?
e) Assuming that a flare ring separation of 5/32(?) is enough so that the ball will always touch clean surface, how much differential and / or sum of angles is necessary as a minimum to achieve this amount ?
f) If the pin is placed beyond the VAL, should flare theoretically be inverted? And if so, does placing the pin nearer the VAL reduce flare ?
g) What kind of layout makes the ball lose axis tilt faster ?
Sorry for the bombardment of "different" questions (apart from the last one which should be routine)
Thanks in advance,
Robert
Questions about... dynamics, layouts, the universe etc...
Moderator: Moderators
- kellytehuna
- Senior Member
- Posts: 2891
- Joined: January 18th, 2010, 11:11 pm
- THS Average: 195
- Positive Axis Point: 3.75", 1" up
- Speed: 18
- Rev Rate: 480
- Axis Tilt: 17
- Axis Rotation: 40
- Heavy Oil Ball: Morich DestroyR
- Medium Oil Ball: Morich Perpetual Motion
- Light Oil Ball: Morich Mojave
- Preferred Company: Morich
- Location: Hazard, KY
Re: Questions about... dynamics, layouts, the universe etc...
If I may take a crack at answering SOME of these.robert wrote:Good evening Mo,
Since it is my 1st post, I would like to start off by saying thank you for devoting your own time answering so many questions.
Having just been through the ibpsia phase 1 training, there are a few holes in my understanding regarding ball dynamics which I am trying to fill, and I believe you may be the only person who could answer my queries.
Some may be trivial, others may be insane, and obviously many may be irrelevant so here goes.
a) Which axis does a drilled bowling ball migrate to ?
According to this:
[youtube][/youtube]
it appears to be the psa. However according to the usbc motion study, only the high diff test ball you provided manages to migrate to a lower rg axis, i.e. closer to the pin.
b) What effect does drilling the ball have on the 60 deg spin time of a ball ?
i.e. if bowling ball X takes 7 seconds to reach it's preferred spin axis, how much does this change when the ball is drilled, and how is this affected by the layout?
c) I we were to swap the primary and secondary pins, which way would the ball flare, and what kind of motion would we expect ?
i.e. with psa near the fingers, pin near the thumb. (skip the balance hole part)
d) How much affect does drilling deep finger holes close to the pin have to reaction, compared to the effect of the layout and the effect of the balance hole ?
e) Assuming that a flare ring separation of 5/32(?) is enough so that the ball will always touch clean surface, how much differential and / or sum of angles is necessary as a minimum to achieve this amount ?
f) If the pin is placed beyond the VAL, should flare theoretically be inverted? And if so, does placing the pin nearer the VAL reduce flare ?
g) What kind of layout makes the ball lose axis tilt faster ?
Sorry for the bombardment of "different" questions (apart from the last one which should be routine)
Thanks in advance,
Robert
a) The ball doesn't "migrate to" any of the major axes (PSA, PIN and Intermediate RG). The ball's path of axis migration will rotate around either the PSA or the PIN depending on the RG of the PAP (The initial axis of rotation). The axis of rotation will maintain an RG value = the the RG of the PAP. The reason the ball "migrates" to the PSA in the video is because energy is being added to the system.
b) I would say the the spin time will decrease with the drilling, though I'm not certain of that. I watched Mo do this last Friday, and it decreased by .5s after initial drilling, then a further .5s after the weight hole was added. I would say stronger layouts would have a more pronounced affect than weaker layouts. Again, not certain of that, but that seems to make sense in my head.
The rest, no idea! LOL! Well, ideas, sure. None worth sharing...
Father, Husband, Bowler, Web developer
15lb Morich DestroyR, Mania, Perpetual Motion, Craze, Frenzy, Mojave
15lb Radical Yeti
15lb Brunswick Slingshot, Avalanche Urethane
Highest score: 279
Highest series: 818
15lb Morich DestroyR, Mania, Perpetual Motion, Craze, Frenzy, Mojave
15lb Radical Yeti
15lb Brunswick Slingshot, Avalanche Urethane
Highest score: 279
Highest series: 818
- Mo Pinel
- Rest In Peace
- Posts: 10054
- Joined: January 26th, 2010, 6:10 pm
- Preferred Company: MoRich, & now RADICAL BT
- Location: Richmond, VA
Re: Questions about... dynamics, layouts, the universe etc...
robert wrote:Good evening Mo,
Since it is my 1st post, I would like to start off by saying thank you for devoting your own time answering so many questions.
Having just been through the ibpsia phase 1 training, there are a few holes in my understanding regarding ball dynamics which I am trying to fill, and I believe you may be the only person who could answer my queries.
Some may be trivial, others may be insane, and obviously many may be irrelevant so here goes.
a) Which axis does a drilled bowling ball migrate to ?
According to this:
[youtube][/youtube]
it appears to be the psa. However according to the usbc motion study, only the high diff test ball you provided manages to migrate to a lower rg axis, i.e. closer to the pin.
b) What effect does drilling the ball have on the 60 deg spin time of a ball ?
i.e. if bowling ball X takes 7 seconds to reach it's preferred spin axis, how much does this change when the ball is drilled, and how is this affected by the layout?
c) I we were to swap the primary and secondary pins, which way would the ball flare, and what kind of motion would we expect ?
i.e. with psa near the fingers, pin near the thumb. (skip the balance hole part)
d) How much affect does drilling deep finger holes close to the pin have to reaction, compared to the effect of the layout and the effect of the balance hole ?
e) Assuming that a flare ring separation of 5/32(?) is enough so that the ball will always touch clean surface, how much differential and / or sum of angles is necessary as a minimum to achieve this amount ?
f) If the pin is placed beyond the VAL, should flare theoretically be inverted? And if so, does placing the pin nearer the VAL reduce flare ?
g) What kind of layout makes the ball lose axis tilt faster ?
Sorry for the bombardment of "different" questions (apart from the last one which should be routine)
Thanks in advance,
Robert
NOTHING LIKE STARTING OFF WITH A BANG!!!!! You have used up your "GET OUT OF JAIL" cards already.
Here goes:
a) Kelly's answer is accurate.
b) Kelly's answer is good. The strength of the drilling technique (mass properties of the drilled ball) will determine the change in time. Some control layouts can length the spin time.
c) It will move the "bowtie" point and can cause the ball to flare over the holes. I recommend you don't consider it.
d) The balance hole size and location has the most effect. The layout is next most in importance. The depth of the finger holes is extremely minor.
e) A drilled ball diff. of about .036" will create enough flare to separate the rings.
f) When the pin is past the VAL, the "bowtie point" will rotate up far enough to cause the ball to flaer over the thumb for some bowlers. Flare will not reduce at all and may increase with pins near the VAL.
g) Smaller drilling angles combined with large flare pin to PAP distances will cause the ball to lose tilt the fastest.
The Advanced IBPSIA Certification Class covers all this in detail with "hands on" training, June 22-25, 2010 in Las Vegas.
Rest In Peace (1942-2021)
Re: Questions about... dynamics, layouts, the universe etc...
Wow, thanks both of you for the responses!
Mo, I would love to be able to join you in Vegas, however the trip to UK (from Greece btw) already put me over budget for a while. So unless I win the lottery, or everyone in my town decides to start bowling and come to my pro shop, I doubt I'll be able to make it, at least not this year.
Since I'm out of "get out of jail free" cards, I'll mull things over in my head for a while, before I post any more questions, although I doubt I'll manage to come up with any more outraging ones like those
Once again, thank you,
Robert
Mo, I would love to be able to join you in Vegas, however the trip to UK (from Greece btw) already put me over budget for a while. So unless I win the lottery, or everyone in my town decides to start bowling and come to my pro shop, I doubt I'll be able to make it, at least not this year.
Since I'm out of "get out of jail free" cards, I'll mull things over in my head for a while, before I post any more questions, although I doubt I'll manage to come up with any more outraging ones like those
Once again, thank you,
Robert