thermal epansion of different materials.
runout in the drill press arbor.

Drill bit not perfectly aligned with the ball so maybe pitches "feel" different.

are the grips the same color? I have noticed differences when I used grips. the same size but some colors here harder and others softer.

also your hands may noticed the difference in a few thousands where the acuracy of the tool, including measureing deveives are off by that much.

so take your knowledge of machine work and apply tolerances and the QC of having one guage of a certian acuuracy meassre and then hake a higher precision guage and measure it.

or maybe he just sucks.


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"deserves got nothing to do with it."
-- William Munny

It sounds to me like he may have justed opened up the WD a bit more compared to the Res.  Maybe he switched out sanding disks or used a new one on the WD first.  There are some variation between finger grips, but the thumb slug should be all user error if they feel like different sizes.

Most people's thumbs change with the weather. No reason to redrill. Sometimes a slight difference in bevel will make a hole seem tighter. A quick shot with the sander should open the hole just a bit. I'm no driller, but the material shouldn't make a difference.

Please delete the duplicate post so you don't get the responses spread out.  Open the other post and click the little trashcan near the top.  It takes about 30 seconds to take.  Thanks.
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Penn State Proud

That's "Mr. Toe" to you.

Ron Clifton's Bowling Tip Archive

I've had a similar experience a couple of years ago when drilling up equipment. From talking with some very knowledgeable ball drillers(1 guy used to drill on the PBA truck). They all scratched their heads for a little while and came up with a couple of theories;
1) Was that the ball material expands and contracts at different temps. thus causing this problem.
2) That because you are drilling into a harder substance(a weight block) in the resin ball. You apply pressure to the drill at a slower more deliberate pace as opposed to the spare ball which drills like butter.
Each drill bit has some "wobble" to it.
So if you drill slower the bit has more time to "wobble" in the hole thus opening it up compared to a quicker plunge into the material.

Maybe the grips you put in were slightly worn from being handled too much or slightly used.
I go thru alot of grips(probably 3 sets per ball) during a season and notice a different feel from time to time when I replace them. I also order my grips in bulk so this should eliminate getting from different batches.

After rereading your original post I'd think that the White Dot would be tighter than the Retro.

is it a thumb alignment problem ? some experienced with the thumb is drilled with 1/16 offset by operator error, it is hard to measure by span (just about 1/32 distance changed) and it caused the feeling different, but it can be sloved by bevel the thumb hole or sanded the offset side with sand paper

I have found that plastic balls drill larger than do urethane, reactive or particle.  I am using carbide bits on a drill/mill machine.  I know this because each time I put a slug (or finger grips) into a plastic ball, they go in really easy, whereas I have to tap the slug with a hammer for the other balls.

I too see a difference in grip "feeling" when they are different colors. So much so that I called Vise and inquired about it and I was correct. The dye in grips changes the densities or "feeling". So I only use black grips and thumb slugs. If it is not black I will not throw it. Even if I have to wait a few days for black grips to come in (I use half sizes, my shop doesnt stock half sizes) so I can drill a ball I will.
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"You can put it on the bbboooaaarrrrddddd, YYYEEESSS!!!"- Da Hawk