Lateral finger pitch guidelines

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Lledsmarttam
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Lateral finger pitch guidelines

Post by Lledsmarttam »

I have seen the finger pitch fan chart in the wiki so please don't direct me there. This is more or less a question, which the answer changes depending on what I read.

Some things I've read say to keep the pitches even or parallel. Ex. 7/16" left and 7/16" right

Now the finger pitch fan chart contradicts that?

Which is correct or more frequently used?
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Re: Lateral finger pitch guidelines

Post by TonyPR »

Finger fan chart does not contradict 7/16, 7/16 in fact it is based on 7/16, 7/16. 7/16+7/16=14/16 which simplifies to 7/8. Add any pair of pitches on the fan chart and the result will be the same 7/8.

The fan chart was developed as an easy way to take a bowlers CLT angle and drill it on a T grip, that’s why fan chart pitches are recommended according to your CLT angle when you lay your hand on the ball. If you were to drill 7/16, 7/16 on the CLT line instead of the T grip line, when you measure the resulting lateral pitches on the T line they will be very close to what the fan chart recommends.

Always adjust for crooked fingers.
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Re: Lateral finger pitch guidelines

Post by Lledsmarttam »

TonyPR wrote:Finger fan chart does not contradict 7/16, 7/16 in fact it is based on 7/16, 7/16. 7/16+7/16=14/16 which simplifies to 7/8. Add any pair of pitches on the fan chart and the result will be the same 7/8.

The fan chart was developed as an easy way to take a bowlers CLT angle and drill it on a T grip, that’s why fan chart pitches are recommended according to your CLT angle when you lay your hand on the ball. If you were to drill 7/16, 7/16 on the CLT line instead of the T grip line, when you measure the resulting lateral pitches on the T line they will be very close to what the fan chart recommends.

Always adjust for crooked fingers.
Ok thank you Tony. I guess I never thought of it that way but makes total sense.
Another quick question if using 31/32 holes with 1/4" bridge wouldn't the pitches have to be 5/8" or slightly less to keep holes parrallel? If this is in fact what you are trying to accomplish?
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Re: Lateral finger pitch guidelines

Post by TonyPR »

The lower the sum of the laterals the more chances you have of the holes intersecting. For no inserts you can use a 3/8 bridge and it will still probably be smaller than the total effective bridge of using inserts and a 1/4 bridge.
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Re: Lateral finger pitch guidelines

Post by JohnP »

Ok thank you Tony. I guess I never thought of it that way but makes total sense.
Another quick question if using 31/32 holes with 1/4" bridge wouldn't the pitches have to be 5/8" or slightly less to keep holes parallel? If this is in fact what you are trying to accomplish?

You're right, if you want parallel 31/32" holes 5/8"L and 5/8"R are very close. The chart is intended to match the pitches to your hand (as Tony explained) with totals that won't come together at normal finger hole depths. -- JohnP
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Re: Lateral finger pitch guidelines

Post by Maine Man »

I am left handed and use 1/8" right lateral (middle finger) and 5/8" left lateral (ring finger). I have used a 3/4" difference for many years and have no problem with fingers touching in the holes. You have to adjust lateral pitches based off finger flexibility of course, but the 3/4" difference works well for the holes not touching at the bottom, whichever way you measure each finger to get there.
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Lledsmarttam
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Re: Lateral finger pitch guidelines

Post by Lledsmarttam »

Maine Man wrote:I am left handed and use 1/8" right lateral (middle finger) and 5/8" left lateral (ring finger). I have used a 3/4" difference for many years and have no problem with fingers touching in the holes. You have to adjust lateral pitches based off finger flexibility of course, but the 3/4" difference works well for the holes not touching at the bottom, whichever way you measure each finger to get there.
My question was more about the holes being parallel, and not about holes intersecting. Reason for the question mostly was because I watched a video on proper ball fit by the usbc and the older guy in the video said to drill fingers parallel to each other so it just got me thinking... I am right handed and use 3/8" left in middle and 1/2" right in ring. I have also seen a lot of different combinations at the 3/4" total as you mentioned
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Re: Lateral finger pitch guidelines

Post by TonyPR »

In my opinion the most important two things in fitting are comfort and reducing grip pressure. Bowling should not hurt. Some people are easily fitted within this or that method, and there are many, others are just plain wierd, for example I have a friend who uses 5/8 right thumb lateral (right handed) and it’s what most comfortably fits him, he has a high rpm release and averages well above 210. What I am trying to say is do what works best for you (or the customer). Remember, comfort and reducing grip pressure.
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Re: Lateral finger pitch guidelines

Post by JohnP »

Parallel finger holes are an old, easy way to drill them. All the driller has to do is slide the jig side to side, line the bit up with the reference line, and punch the hole. No rotation of the ball is required as would be necessary for anything other than what's referred to as "parallel zero". -- JohnP
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