Help needed with thumb fit

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Bakerboy
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Help needed with thumb fit

Post by Bakerboy » April 15th, 2019, 9:39 pm

Hi,

I am based in pakistan and unfortunately we have no proshops.. So i ordered 2 switch grips for my thumb.. Now i want to drill the inner sleeve and i dont know what my size is.. When i measure it with caliper 22 is edge to edge on thumb the fattest part of my thimb left to right and 23 is alightly loose but on my friends ball 23.5 is a decent fit .. I dont know what fit would be perfect i fear 22 even though perfect would be a bit tight or should i gonwith this? Is there a proshop that would drill it for me i got it from cheapbowling.com but they dont offee the service as far as i know thanks

MineralitePaul
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Re: Help needed with thumb fit

Post by MineralitePaul » April 15th, 2019, 9:55 pm

Bakerboy wrote:Hi,

I am based in pakistan and unfortunately we have no proshops.. So i ordered 2 switch grips for my thumb.. Now i want to drill the inner sleeve and i dont know what my size is.. When i measure it with caliper 22 is edge to edge on thumb the fattest part of my thimb left to right and 23 is alightly loose but on my friends ball 23.5 is a decent fit .. I dont know what fit would be perfect i fear 22 even though perfect would be a bit tight or should i gonwith this? Is there a proshop that would drill it for me i got it from cheapbowling.com but they dont offee the service as far as i know thanks
I would go with the looser fit and use tape as a shim.

Just curious: does your ball already have a Switch Grip outer sleeve in it? Do you know what your thumb hole pitches are? Also,you don’t say what your narrow oval dimension is. Additionally, if you know your thumb oval angle, I’d be glad to drill some inner sleeve/slugs and ship them to you. It must be tough with no pro shop around.

Bakerboy
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Re: Help needed with thumb fit

Post by Bakerboy » April 15th, 2019, 10:18 pm

Very toughbindeed. Thank you for your help.. I just purchased the outer sleeve i will drill 1 1/2 drill bit which is around 38mm for the outer sleeve for my thumb i just took from left to right the largest possible where my thumb pops upon the outer part (oval) that is the thickest part in thumb and that is whats 22 mm i dont know jow to take measurements of my oval part dont know if its different?

Bakerboy
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Re: Help needed with thumb fit

Post by Bakerboy » April 15th, 2019, 10:25 pm

Ok i dont know if it will make sense

But from bottom the measurement is around 19 at the oval its 22 (oval) part and then 19 again

MineralitePaul
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Re: Help needed with thumb fit

Post by MineralitePaul » April 16th, 2019, 11:33 am

Bakerboy wrote:Very toughbindeed. Thank you for your help.. I just purchased the outer sleeve i will drill 1 1/2 drill bit which is around 38mm for the outer sleeve for my thumb i just took from left to right the largest possible where my thumb pops upon the outer part (oval) that is the thickest part in thumb and that is whats 22 mm i dont know jow to take measurements of my oval part dont know if its different?
How do you plan on drilling the outer sleeve hole? Do you have the special drill bit with the stop collar on it? Do you have good solid drill press?

Bakerboy
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Re: Help needed with thumb fit

Post by Bakerboy » April 16th, 2019, 11:45 am

Do i need a apecial drill bit foe the outee sleeve? Any place where i can oreee it online? Yes the guy who drillee my thumb before has a big drill machine but i goce him the drilll bits and i dont think he has the stoper.. Any place to order it online?

MineralitePaul
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Re: Help needed with thumb fit

Post by MineralitePaul » April 16th, 2019, 3:17 pm

Google “Switch Grip Drill Bit”
One such website is: https://www.buddiesproshop.com/pro-shop ... ght-shank/" onclick="window.open(this.href);return false;

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VLe
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Re: Help needed with thumb fit

Post by VLe » April 17th, 2019, 10:59 am

If you are going to drill only few balls DIY-method, you can use "normal" 1,5" drill bits. I have one with 10mm shank... Of course it is not nearly as good option compared to a proper bowling ball drill bit but does the job. Make sure it is sharp though. I use normal drill bits for most holes at home. For making ovals I use the 18mm router bit (extra lenght) I ordered online. It is a bit tricky process and a good xy-table is a must but works fine for me after practise.

Get yourself some old, maybe even cracked bowling ball to make test drillings for your thumb then see how it feels. Dont go straight into drilling the SG or you will most likely end up ruining it.

If you need some method to measure existing pitches, here is one that I made some years ago (BB Pitch Guide 2.0. still using it):
viewtopic.php?t=12631" onclick="window.open(this.href);return false;
Right Handed
PAP 4 3/8" x 0"
60* rotation
17.5* tilt
320-360 rev rate
17mph off hand

Bakerboy
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Re: Help needed with thumb fit

Post by Bakerboy » April 18th, 2019, 10:51 pm

Thanks i'm going to give it a try and see what happensnthanks guys for your help.

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