Deflect Test

Johnnyt

Burn all jump cues
Silver Member
I tried that test that the machine in a tread showed for diferent shafts(can't find the old thread). From 6-foot away and two tips of left shooting at med-hard , my Viking with stock shaft hit the outside edge of the 1-ball on the rail all five times. My Dale Perry with his standard shaft hit it just about dead center all five times. I can't see how that machine got 5'' difference with what are suppose to be top of the line LDS. Am I doing something wrong? Or is that machine just a gaff? Johnnyt
 
FYI, I have links to some data and additional resources on this topic here:


Regards,
Dave

I tried that test that the machine in a tread showed for diferent shafts(can't find the old thread). From 6-foot away and two tips of left shooting at med-hard , my Viking with stock shaft hit the outside edge of the 1-ball on the rail all five times. My Dale Perry with his standard shaft hit it just about dead center all five times. I can't see how that machine got 5'' difference with what are suppose to be top of the line LDS. Am I doing something wrong? Or is that machine just a gaff? Johnnyt
 
are you shooting completely level with the table? that's how the test should be, otherwise swerve will cancel some out. every shaft causes squirt
 
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Dr. Dave -

I know the accepted wisdom is that squirt doesn't increase with shot speed, that it only appears so because swerve cancels out some of the squirt at lower speeds. But that sure goes against my "naked eye" tests as well as what your video shows.

How sure are you that squirt doesn't increase with shot speed?

Edit: Uh, never mind, as Roseann Roseannadana used to say. I read your article reviewing the robot tests, and it pretty much puts that idea to bed. Thanks for all your work on these issues.
 
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One thing you have to br extra careful about is how you apply the english. You must not line up with dead center and pivot to the side. Pivoting cancels out some of the effect of the deflection because you are now aiming your cue to the left or right of the original sight line. This is the basis of the pivot-based aiming methods.

You must slide the cue over parallel to the original sight line every time to ensure your tests have precision (repeatability).
 
Dr. Dave -

I know the accepted wisdom is that squirt doesn't increase with shot speed, that it only appears so because swerve cancels out some of the squirt at lower speeds. But that sure goes against my "naked eye" tests as well as what your video shows.

How sure are you that squirt doesn't increase with shot speed?

Edit: Uh, never mind, as Roseann Roseannadana used to say. I read your article reviewing the robot tests, and it pretty much puts that idea to bed. Thanks for all your work on these issues.
I'm glad you answered your own question, and I'm glad my articles helped.

I'm not sure which video you are talking about, but if it is the one I am thinking of, the swerve happens very quickly over a short distance with the slower shot speeds, so it is difficult to see ... it just looks like less squirt right off the tip.

Regards,
Dave
 
I tried that test that the machine in a tread showed for diferent shafts(can't find the old thread). From 6-foot away and two tips of left shooting at med-hard , my Viking with stock shaft hit the outside edge of the 1-ball on the rail all five times. My Dale Perry with his standard shaft hit it just about dead center all five times. I can't see how that machine got 5'' difference with what are suppose to be top of the line LDS. Am I doing something wrong? Or is that machine just a gaff? Johnnyt

Are you using the same kind of tip on both shafts?
 
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