Things I've already learned from my DeTerminator

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Glenn
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Re: Things I've already learned from my DeTerminator

Post by Glenn »

Hmm, this thread really interests me. I've never really paid attention to how long the spun ball locks on the drilled PSA position -- I've always taken the timing as soon as the ball locks and moved on. When I reviewed Mo's videos on the subject, the balls all seem to stay locked on -- I don't believe that any of mine do. So, I loaded up six drilled balls of various flavors -- sym & asym, balance holes & no balance holes, aggressive & less aggressive, different layouts, all statically balanced to within 1/4 oz. I spun them without regard to timings -- just wanted to see if they would stay locked on and let them spin for about 30 seconds (man that seems like a long time - LOL). The PSA location and the thumb holes are all very close to each other on all of these balls.

And, just as I thought, none of these balls stay locked on for any appreciable time. The ball that I like the least (asym with balance hole) will almost immediately move to the PSA location, hesitate briefly (less that a second or two) and then drift away, only come back in the general location of the drilled MB, and just drift in and out.

My two stronger balls (one asym & one sym both with balance holes) lock on the longest, but that lasts only several second before they drift in and out.

I guess that the large thumb hole might have an impact in the early stage of the spin, but once the thumb hole moved into the locked position area, it should not. The one-inch finger holes and the 1 x 3 balance holes might continue to knock it out of lock as I notice the balls all thump as they spin. Maybe I need to find some way to temporarily plug these holes and see if that has any impact.

I guess I am surprised that none of my bowling balls stay locked when in all the videos I see of the DeTerminator indicate that they can and do. Something must be impacting my results that I am missing??
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stevespo
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Re: Things I've already learned from my DeTerminator

Post by stevespo »

Glenn,

I do have a few pieces that lock in quickly and spin quite stably.

I would say that most find their MB and then kind of (slightly) cycle in and out, like you describe. So, I've never been quite sure how to reconcile that either. I think somebody mentioned it could be from rolling over a balance hole, over the finger holes, a slight out of round, etc.

When I see the MB stabilize for a second or so, I'll treat that as the spot and mark it with a larger diameter circle. When I spin it again and see that circle, I'll take my spin time reading. So, I'm trying to be consistent.

I'll have to pay more attention and try it with a couple of new/undrilled balls to see how those compare.

Steve
16 mph (14-14.5 on monitor), 375 rpm, PAP 5 1/2 x 3/8 up, AT: 12*, AR: 45*
Glenn
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Re: Things I've already learned from my DeTerminator

Post by Glenn »

Steve, I got a little time today and threw my suspect ball back on the bench. This is the ASY with a 60x4x40 P2 balance hole that is statically balanced. In my previous post, I always assumed the drilled PSA was when the spun ball briefly locked on to the thumb hole. Today, I went through the process of looking for the drilled PSA by spinning the ball on the right and left side of the DeTerminator. I put the grease pencil on the outside of the column and got a bunch of circles in close proximity to each other. Those circles formed a pattern showing the likely location of the Drilled PSA (it was not the thumb hole, but about one inch right of it).

I marked the drilled PSA and spun the ball numerous times to get timings. I noticed that each time I spun the ball, it would initially and briefly lock on to the thumb hole in about 2.5s. I continued to let it spin to see if it would migrate to the marked drilled PSA location, and it did in about 6.25s on the average. So, rather than having an unusually fast spin time for this weak ASY, I have a benchmark timing which makes more sense.

The large thumb hole must be having an impact on the balance hole pulling the PSA away? And this may have something to do with why I have never really warmed up to this ball.

Glenn
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