New: The MoRich double thumb technique: http://www.morichbowling.com/MosCorner/DoubleThumbDrilling/DoubleThumbDrilling.htm

This is used for figuring out what your maximum hook drilling angle would be on your next ball, not altering an existing ball, although it may coincidentally be one and the same for you.

The Dual thumb technique finds your optimum mass bias angle for max hook by taking an existing ball and measuring 30 degrees from the vertical axis line (line from positive axis point to negative axis point) and measuring 4" up from the pap on this line then making another line to 1/2" to the right of the thumb (left of the thumb for lefties) then figure the angle made between these two lines. If the angle for instance comes out to be 60 degrees, then your maximum hook mass bias angle would be 60 degrees from your pap. Since 60 degrees puts the mb too close to the thumb for a max hook weight hole Mo suggests drilling a weight hole 1 1/2" away from the center of the thumb, pitched 3/4" right (left for lefties) no bigger than 1 1/8" in diameter for usbc regs.

Jim; Well explained. I have been in the Pro Shop industry for over 15 years and can say you know your S#it.. Since this is a BASIC layout thread the only thing I can add is that the distance of the MB has to change in layout depending on the strenght of the MB or Intermediant Diff. (sp?) example the Virtual gravity. if you close the angle down like u might on a regular ball with less InDiff you wont get the radical motion that the ball has to offer.. I drill all VG's with 60deg. or more unless the customer wants less reaction. the strenght of the InDiff is very important too...

Corey I'm not sure I understand what you are saying, are you saying that if you are trying to match another ball's reaction to the vg then you need to compensate for the mb diff by altering the mb angle?

From Mo's Dual angle system he says that smaller angles cause the ball to use more energy at the break point, larger angles cause the ball to spread the ball's energy over a longer distance.

From my own experience, drillings only make a difference when, comparing the same ball. Meaning if I have a vg drilled with a 60 degree mb and another with a 25 degree mb then the 25 degree will burn more energy before hitting the pins than the 60.

If you are comparing a 60 degree vg vs a 25 degree uprising then the vg will still burn more energy before it hits the pins, because the overall design of the balls are so different the design characteristics will be a larger factor in ball motion than the drilling.

Well how I see it is the varying InterDiff is getting to be as important as the pin distance to the PAP. I understand what Mo is saying, but if you took 2 ball with similar shells and surfaces (1 with a IntDiff of .014 and 1 with a .033) and you put the same layout on them they would reaction quite differently. The stronger the IntDiff gets the wider the angle needs to get. By saying you stick the the formula on the angles is saying you use the same pin distance for all balls no matter what the diff is. Let me know that you think..

Corey

What about symmetrical balls with no intermediate diff and the same coverstock?



Agreed because the ball with the .033 int. diff has a stronger core. Are you saying that you could drill the .014 diff ball to match the .033 layout ball?

What I'm saying is you need to take all of the ball's characteristics into consideration before laying the ball out, I never said I would layout every ball the same. I am also saying that intdiff angle is not as big of an influence on ball motion as pin to pap distance and pin to val angle.



How do you figure that? Every drilling has it's time and place to be used. I never said use the same pin to pap distance for every ball.

I know you never said that about the Pin distance... I was just using it as an example. And no you cant make a .014 react like a .033 just like a ball with a regular Diff of .030 and .050 with varying pin distances wouldnt react the same. But if you had two balls with similar shells and InterDiffs of .014 and .033 and your layout was the same they would react differently. My statment earlier about the VG's and laying them all out at 60 degrees is was a generalization. Most of them are around 60. I had a guy yesterday I sold one to and he strapped the ball hard. I drilled his 6"X80X45 and that ball rocked harder than most of the previous VG's I have ever seen. I threw it and it really defied most of the logic that I have understood about MB placements. This layout put the MB under and a tick left of the thumb and the pin around the middle finger. I have never seen more strenght and motion released off the spot EVER! so if varying the InterDiff isnt looked over atleast, you might not achieve the reaction one is looking for. Knowing this could make the difference in a customer that is happy and leaving ten pins or really excited about his flying scouting ten pin crushing new orb.

The Doc

Corey, that layout put the ball very near its highest RG point, which would have had a similar effect as using a longer pin distance with a lower drilling angle.

The low RG axis is generally around the pin, and high RG axis is 6 3/4" away from both MB and Pin. So, a ball with a 90* drilling and a 6 3/4" pin would put the high RG on the PAP. As you can see, your drilling was pretty close to that, so the ball was storing about as much energy as possible. Since the cover is strong enough to use that energy, you got the explosive reaction. On a weaker cover, that ball would probably not have gone through its hook phase fast enough.

Agreed

I have a question, I was wondering how to figure out how my virtual gravity was drilled. A lot of people talk about how they have (just an example) a 5" x 4" x etc. and I dont know how they figure that up so I was wondering how I do that and what each of those measurements mean. Thanks

If you see 20x5x45 hole on mb that means the pin is 20 degrees from the val x 5" from the pap with the mb 45 degrees from the pap and the hole on the mass bias.

Look at MoRich's dual angle drilling technique on www.morichbowling.com