Picture the weight block as a pencil with the pin being the eraser.

If you place the pin on the pap then the ball will rotate around the horizontal axis of the pencil and not flare at all. This is the lowest rg drilling for a ball.

1/4 of the circumference of the ball is 6 3/4" if you were to place the pin 6 3/4" from the pap the pin would run in the bowler's track and the pencil would be straight up and down and revolving end over end this would cause the ball to also not flare and this would be the highest rg drilling for the ball. The difference being the lower Rg drilling will rev up the fastest, and the high rg drilling will go the longest, but neither will flare.

Flare is what causes the ball to roll over a fresh part of the coverstock if the ball doesn't flare then it will roll over the same part of the coverstock and track oil down the lane having the ball flare and roll over a clean part of the coverstock creates more friction between the ball and the lane and creates earlier hook. To drill a ball for maximum flare you will place the pin 1/2 way to the track or 3 3/8" from the pap. Pin distances longer than 3 3/8" go longer and hook harder pin distances shorter than 3 3/8 rev earlier and hook less.

Next the line from the Pap to the Negative axis point is called the vertical axis line. Placing the pin near the val causes the ball to react violently at the break point, placing the pin farther from the val causes the ball to expend it's energy over a longer period of the ball's motion.

Next mass bias placement, placing the mass bias closer to the pap makes the ball snap hardest on the back end, placing it farther up to 90 degrees will make the ball arc more on the back end. Balls that do not have a mass bias are called symmetrical and just have a marked center of gravity. The position of the center of gravity doesn't effect ball motion; however the placement of the weight hole does, so we place the cg in a position to cause a weight hole to be placed in the desired location to get the desired ball reaction.

Admin: +1 for pinning this or a similar thread to the top

Since it was asked in another post I will add my reply to explaining mass bias placement in ball layout here.

Shifting the mass bias closer to the pap makes the ball react quicker off the break point. Similar to putting the in closer to the vertical axis line or "above the fingers".

Shifting the mass bias closer to 90 degrees makes the ball react over a longer portion of the lane or "arc", similar to drilling the ball with the pin below the fingers.

Placing the mass bias farther than 90 degrees can have negative effects on the back end and can cause negative flare in some balls.

Symmetrical balls just because they have a long pin to cg measurement do not have an "implied mass bias" as the whole weight block is shifted in that direction, not just a part of the weight block, so you will not get the same reaction results. It has been proven that shifting the cg does not change the reaction of the ball unless it is shifted a ridiculous amount and would require a weight hole that would change the results anyway. What matters with symmetrical balls is weight hole or no weight hole and where to place the weight hole to get the desired results.

a very good article on drilling patterns was in this months issue of Bowling This Month.

Another interesting layout resource is Mo Pinel's Dual Angle layout system. The one site I know of that has a good writeup is a banned url, so just google "Mo Pinel Dual Angle". The first result should be good.

The article in BTM is a bit outdated, I would regard Mo Pinnel as more of an expert. His dual angle drilling system is the basis for my writings, which differs from the article in BTM.

For example placing the pin above the fingers doesn't make the ball go longer then placing it below the fingers. What happens when you place the pin above the fingers is the ball will expend more energy at the break point than a ball with the pin below the fingers that will continue to hook past the break point. So if you are leaving a bunch of weak 10 pins try a pin under fingers layout in a similar or same ball. The opposite is true as well, if you are leaving a bunch of solid back row spares to shoot at try a pin above the fingers drill in the same or similar type of ball.

There was a hotly debated thread earlier about track flare. I am letting that one stay dead, but I just got off the phone with Brunswick, and I got some good info that belongs in this thread. I am also in touch with some other ball companies, and will post their answers as I get them. If you want to argue points, please rekindle that old thread, or start a new one and keep this one clean. Thank you.

The original question was "How does track flare affect length and backend reaction?"

Please note that the during this conversation, neither he nor I ever brought up any aspect other than track flare. Bowler, coverstock, core, lane condition, none of it. Tom at Brunswick and I had a very good conversation, and here are the contents of my notes:

• With the pin on the axis (PAP), the ball will not flare.
• With the pin 3 3/8", the ball will see the most flare (this is of the ball's potential)
  • Interesting side note, the ball needs to flare 5/16" per ring to get fresh surface on the lane.
• More flare leads to:
  • An earlier roll.
  • More friction.
  • Less back end. This is because the extra friction causes you to lose revs in the front part of the lane.
• He also said that a drilling with a pin distance of 5 1/16" will give the most length with the most back end potential. This requires a lot of revolutions though (I didn't write down the number, but I think he said 14-15).
  • 
    Note from my mouth, not his: that number will be condition specific. He probably gave me that number based on a typical house shot. It will also be release specific - a ton of revs isn't going to give a ball back end if it has no axis rotation.

If anyone has serious, non-abrasive follow-up questions, I can pass them along.

Great follow up Cgeorge, I have a few follow up questions if you don't mind asking:

1. Will a pin closer to the pap than 3 3/8" go longer than the 3 3/8" drilling? In my experience like I said it went longer with less back end, but also like I said it was a plugged ball and I don't trust any reaction I would have gotten from a plugged ball.

2. How much differential does a ball need to have to get 5/16" between flare rings.

3. Does drilling a pin distance longer than 5 1/16" from the pap make the ball go longer with a less jumpy backend, or does it just go longer with a more jumpy back end? I personally have not had a 6" pin to pap distance ball to compare since I mostly bowl on a house shot that has enough oil in the middle for a dry lane ball like an ice or bash, but if I did I would think it might go long then stand up, more than jump, and the pin axis drilling will go long then lay down.

All of this, except where noted by "I assume," etc., is from the Brunswick rep.



The 5 1/16" drilling he mentioned is apparently a half-leverage drilling - it's halfway between the 3 3/8" and 6 3/4". The similar drilling on the other side is 1 11/16" from the PAP. It would exhibit the same distance between flare rings, and have similar length to the 5 1/16" drilling. The difference is, the short pin distance would get into a roll earlier (lower RG), and the longer pin distance would skid more (higher RG). The difference wouldn't really be noticeable without using a CATS-type system. Both would go longer than 3 3/8".



I didn't get a number. He confirmed that the separation of rings is the same for a low rev player vs. a high rev player, but also said that higher rev players are able get more out of it... I am assuming he meant more total flare from potential of the drilling. The tangent to this one is that when they first started doing differential balls, they kept them very high - .05 or higher even. This way, even if the driller missed on the drilling by an inch, lower-rev bowlers could still see plenty of flare and separation. Then they started going down a little lower, especially because their pro staff had such rev rates that with a high diff ball, they couldn't really drill the flare out of it without killing the reaction. In the .03-.04 range, from what I gathered, you have a good combination of being able to drill leverage for lower-rev players, and lower flare drillings for higher rev players.



Going past 5 1/16" will bring hand position much more into play. If you release with 90 degrees of rotation, you'll see more backend. If you release with 45, you'll see less. If you go up the back of the ball, it will not move much at all.

First, let me thank you for all of the info.



What he means is that the low rev player and high rev player will each have the same distance between the flare rings if they each used the same ball, just the high rev player will have more rings and a wider flare pattern, but the same distance between rings.



The USBC put a limit on differential at .06 that is why they lowered the differentials. You can still drill a high diff ball to flare less, that is why I was asking what differential was to flare 5/16". This is a significant number because anything less means the ball will track more over the flare and skid farther because of the extra oil on the ball, and anything more would mean the ball is stronger and for heavy oil.

If let's say since we don't know the differential to get 5/16" of distance between flare rings, lets give it an arbatrary number since we know it is a medium differential, lets say .045. This means a ball drilled leverage at .060 will give you close to 7/16" or 1/8" more flare. So if you have a .060 ball and you want to drill the flare back to 5/16 because that is what works best for you, then all you have to do is drill the ball 1/4 of the distance from 3 3/8, to 6 3/4 or 0 and drill the ball with the pin 4 1/4" from the pap and you will cut the flare back to where it matches a leverage drilled .045 diff ball. Remember .06 is the max differential at the leverage point and goes back to zero at the pap and 6 3/4" from the pap.

I guess he will not tell you the diff number because it is a trade secret.