Post by: islenmetfan4life on January 25, 2012, 11:41:34 PM
I've always wondered what effect putting the mass bias in the thumb hole would have on ball reaction. Would it be dependent on one's axis/speed/revs etc? Is there a specific ball reaction that drilling out the MB would generally yield? Thanks.
Post by: Russell on January 26, 2012, 09:24:20 AM
Little known fact: In Russian "Hope" and "Change" translate to "Tax" and "Spend"
Post by: tenpinspro on January 26, 2012, 03:07:37 PM
If we go back to my age old example of mass bias being the handle on a coffee cup and we drill out the handle (or part of it), common sense tells me it would now basically have less effect then it did whole. Based on our magic number of .008 for mb's to have influence, it would depend on how much you actually drill out and if it falls below this number. So in total, it should reduce the effect or strength of the mb in whichever placement it was put to create a desired reaction.
Meaning, if we placed mb to roll early, now it should not roll quite as early and if we placed it to go long, it should not roll quite as long. It all depends on the initial placement and of course how much volume physically gets removed. In theory, if you could drill out the entire mass bias weight, we would just end up with a symmetrical core (so to speak) with the exception of what is already created from drilling gripping holes. Hope this helps some...
Rick Leong - Ten Pins Pro Shop
Tag Team Coaching - Co-Founder
"El" Presidente of the Legion
Post by: xrayjay on January 26, 2012, 05:06:59 PM
And the "coffee cup handle" brought me back almost 6 years past......lol
Tag Team Coaching Success Story 
AKA: addik
Post by: bowler001 on January 26, 2012, 05:32:10 PM
The MB strength, or intermediate differential will increase if you drill through it. You can see the effects here....If you look at the 70x4.5x20 layout, you will see the thumb hole goes through the MB and increases the undrilled int diff from .015 to a drilled int diff of .029 http://wiki.bowlingchat.net/wiki/images/4/4a/Gradient_Line_Hand_Out.pdf
Doug Morton
Xclusive Pro Shop - Anchorage, Alaska
Brunswick Pro Shop Staff
The opinions expressed are solely those of the writer and not of Brunswick Corporation.
Post by: tenpinspro on January 26, 2012, 05:54:50 PM
Thanks Doug for the clarification. I was thinking symmetrically or to a point where if a weak mb were drilled out entirely, it would no longer exist (to a point). Certain angles into the mb can and do alter strength as shown. I wonder if the opposite happens if hole is placed on the opposite side of mb, would it then reduce strength if hitting one side increases it?...
On edit: sorry I didn't clarify more about creating a higher intermediate diff with "gripping holes" but did learn this one a long time ago working for Del Warren and Brian Pursel. The dual thumb was one of the later things that Mo has come up with though that was interesting. That man never stops...
Tag Team Coaching - Co-Founder
"El" Presidente of the LegionEdited by tenpinspro on 1/26/2012 at 7:43 PM
Post by: JustRico on January 27, 2012, 09:19:18 PM
That is not completely true....if you have asymmetry that is created by an oblong core, then adding a hole into the PSA or mass bias will increase the differential as you are reshaping the core. If you have a core that has the asymmetry created by using a denser mass or a piece/knob, by drilling the mass out you actually are making the core more symmetrical thus lowering the differential or smoother the core out.
So you have to first know how the asymmetry is created.
Thus in some cases by placing the PSA/mass bias in the thumb you can increase the overall reaction or decrease it taking into account the distance the mass bias is from the PAP. Another factor is by the strength of the pin to PAP distance....if you have the pin at or close to leverage, the flare is at a point of maximum potential which actually in most cases lowers the strength or influence of the position of the PSA/mass bias.
The views and opinions expressed by myself are solely those of mine and NO one else, nor are they affiliated with anyone else.
Post by: kidlost2000 on January 27, 2012, 10:16:02 PM
The PSA/MB moves towards holes drilled, and the low rg axis/pin moves away from holes.
So when you drill a ball with the MB/PSA near the thumb that PSA then shifts towards or into the thumb. Hole depth is more important then hole size when it comes to the effects on the bowling balls diff because the deeper the hole the more likely you are to remove more of the core, which is the denser part of the bowling ball. So you can imagine when drilling a thumb the effects it has on the bowling ball core because of how deep the hole is and size and likely hood of it removing a large mass of the core. This is increased as mention when it comes to drilling an actual hole through the mb, or near it. It is just creating a bigger leverage.
"1 of 1."
Post by: tenpinspro on January 28, 2012, 01:57:08 AM
Thanks Ric,
I just got the "technical" answer back from my old boss. If the mb logo is the high rg plane, then drilling into will increase the differential vs if the mb logo were the medium rg axis, then drilling into this would decrease the differential (which is what I was thinking) creating more symmetry. Your definition is much simpler for others to understand I'd think (thanks again)..
Rick
Post by: JustRico on January 29, 2012, 08:29:15 PM
I am not sure if mine is a just a simpler way to look at it as well as not as technical...but I do not believe that there is any balls that the mass bias is not on the intermediate axis.
In a symmetrical core ball, the low RG is the X axis and the high RG is the Y axis....in asymmetrical core balls, the Z axis is the intermediate.
The way the dynamics of the core are changed is by drilling into them. In a symmetrical core ball, drilling anywhere along the high RG plane or Y axis which is 6 3/4" from the primary pin or low RG axis, creates the strongest amount of asymmetry, the larger or deeper the hole the more it affects the dynamics.
The way the dynamics of the core are changed is by drilling into them. In a symmetrical core ball, drilling anywhere along the high RG plane or Y axis which is 6 3/4" from the primary pin or low RG axis, creates the strongest amount of asymmetry, the larger or deeper the hole the more it affects the dynamics.
If there is a certain amount of asymmetry created by the Z axis, you are creating asymmetry one way or another. You either are using an oblong core, one that has the low RG or X axis, the wider portion would be the Y axis and the narrower portion is the Z axis. Drilling into the Z axis reshaping the core increases the asymmetry. If you use a symmetrical core ball and add a denser piece to create the Z axis or a mass bias, drilling into this mass lowers the asymmetry by reshaping closer to a symmetrical core ball.
The views and opinions expressed by myself are solely those of mine and NO one else, nor are they affiliated with anyone else.