Copying a Switch Grip with unknown specs

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Copying a Switch Grip with unknown specs

Post by ModernGame » May 29th, 2019, 5:29 am

Hey All,

My pro shop has a new operator. He's a good guy but has not yet had any formal training (our center is hopefully sending him to Innovative Bowling's Pro Shop class at some point), and I certainly don't know what I am doing in regards to switch grip installation. I use switch grips that were installed at another pro shop, and I was wondering how a pro shop operator would copy my ball in regards to the pitches of the thumb hole he would need to drill to install the outer sleeve of the switch grip. The pitch gauges he has are too small to accurately measure the pitches of the outer sleeve itself.

Do we measure the pitch of the thumb hole with my inner sleeve inserted into the ball, or is there another way to check and make sure that we drill the outer sleeve hole correctly?

Any help is greatly appreciated

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Re: Copying a Switch Grip with unknown specs

Post by stevespo » May 30th, 2019, 5:04 am

I'd suggest you just find a qualified, experienced pro shop... I do know that can be difficult, so here are a couple of ideas.

Vise and Turbo recommend drilling the pitches into the ball to accept their permanent inserts. The hole in the removable slug is neutral, ie. no pitches. The hole should look centered in the slug.

However, some shops do drill the outer sleeve neutral (0,0) and then drill the pitch into the removable slug - which works for large slugs and small pitches. You may be able to tell that it has a pitch when it's inserted into the ball.

I have the Jonell pitch gauges and you're right, they are not able to give you the pitch of the large outer (permanent) sleeve in the ball. Find something you can use to shim the opposite sides (2 identical spacers) to effectively reduce the diameter and you might be able to take a good reading.
The Master pitch gauge registers differently and works well for me, but not everyone has one.

You might also find that there is pitch in both the ball and the slug, in which case I'd fix it when I went to replicate the overall (additive) pitches. I have seen this as well. It's frustrating.

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Re: Copying a Switch Grip with unknown specs

Post by MineralitePaul » May 31st, 2019, 1:16 pm

Jonell makes a very nice pitch gauge for measure large holes such as SG and IT outer sleeves use. If you do this kind of work, it’s a must-have.

In lieu of a pitch gauge for large holes, one can drill a concentric hole in each type of interchangeable thumb system’s inner sleeve and/or slug (depending on the system). Cut them short so they never stick out of a pitched interchangeable outer sleeve/hole.

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Re: Copying a Switch Grip with unknown specs

Post by imagonman » May 31st, 2019, 3:36 pm

Or...………… can print this out & use it. Don't cost anything$. VLe posted this years ago here, I've used it w/ great success.
BB Pitch Guide 2.0_LETTERsize.pdf
VLe Pitch gauge instructions.jpg
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