Circular Cracking

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Viper
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Re: Circular Cracking

Post by Viper »

Dustin wrote:I have seen this on and off also. Seem like pitches 3/8" or > and those who track close or over the thumb are more likely to crack but not in all cases. Have seen pitches < 3/8" and those who don't track close to the thumb also crack. Sometimes it's just 1 hair line, sometimes its the circular cracking and most of the time there is nothing at all. Recently I have started to take a bevel knife and "knock off" the edge of the hole before installing the O.S. and going to see of this helps reduce the chances of cracking. There is a Pro Shop that I seen bevel the top A LOT which I guess would help but I think looks a little sloppy (for lack of a better word).
Dustin,

My thumb is zero/zero--both the hole drilled for the OS and my thumb slug itself. I track close to the thumb if I have a bad release, which I am prone to do every now and then, but usually my track is at least an inch away from the thumb hole. Funny your statement about looking sloppy, I told the driller that I wanted a distinct but subtle line between the coverstock and the OS. I hope that translates.

Please update and let us know how your bevel technique works out.

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Re: Circular Cracking

Post by VLe »

How loose is your sg inner slug to the hole? Does this always happen with the same inner slug?

Some things that I have thought about circular cracking is that it is most likely happening when the edge of the cover yields towards center of the hole because lack of support material. Hard and modern very thin coverstocks will have further effect on this also. Plastic balls are prone to this because they are very hard. When the ball hits lane or pins there are very high stress on the coverstock if it hits near the hole. This circular cracking happens a lot in finger holes also. Recently I have seen this happening a lot with interchangeable finger inserts (IF) that dont even use glue. Usually the people having problem with finger cracking are full roller/high track players. One guy that uses these inserts have (for some reason) this cracking problem always with columbia300-balls. Maybe its coincidence, maybe not.

You seem to have large thumbhole and therefore quite thin thumbslug. Make sure the slug is not loose.
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Re: Circular Cracking

Post by Viper »

VLe wrote:How loose is your sg inner slug to the hole? Does this always happen with the same inner slug?

Some things that I have thought about circular cracking is that it is most likely happening when the edge of the cover yields towards center of the hole because lack of support material. Hard and modern very thin coverstocks will have further effect on this also. Plastic balls are prone to this because they are very hard. When the ball hits lane or pins there are very high stress on the coverstock if it hits near the hole. This circular cracking happens a lot in finger holes also. Recently I have seen this happening a lot with interchangeable finger inserts (IF) that dont even use glue. Usually the people having problem with finger cracking are full roller/high track players. One guy that uses these inserts have (for some reason) this cracking problem always with columbia300-balls. Maybe its coincidence, maybe not.

You seem to have large thumbhole and therefore quite thin thumbslug. Make sure the slug is not loose.
My slug/innersleeve is not loose. In too many cases it's too snug, forcing me to use the Turbo tools to lock it in and then to unlock/extract.

And while on that topic, why hasn't Turbo produced something that I can use to ream the inside of the outer sleeve? As I just mentioned, too many times it's a pain switching my slug/IS set-up from ball to ball because the cores are swelling. The Easy Flip I cannot even get an IS into any longer.

Of course, if someone has a good tip on how to open up the hole in the OS down the last 1/3 of its length, I'd appreciate knowing.

I've noticed too that one IS will fit and a second one won't. What's up with that? Might be time to ditch the Turbo system.

Thanks for your help VLe.

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Re: Circular Cracking

Post by Dustin »

Most of the cracking around finger holes has been because a lack of beveling, as for opening the outer sleeve I think a 1 3/8" drill bit run down the inside of the outer sleeve will do the trick. Heard Mo and Scott Pohl talking about this and I'm almost positive he did it on my Fix. He also used the reamer the you can buy from Turbo but had to still drill out the outer sleeve (Radical, DV8 and Big B have very dense cores). As for using the other systems out there I have seen the cracking happen with the Vise system also. Don't drill many Columbia balls but the few lower level balls I have drilled seem to have a very thin cover also.
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Re: Circular Cracking

Post by Viper »

Dustin wrote:Most of the cracking around finger holes has been because a lack of beveling, as for opening the outer sleeve I think a 1 3/8" drill bit run down the inside of the outer sleeve will do the trick. Heard Mo and Scott Pohl talking about this and I'm almost positive he did it on my Fix. He also used the reamer the you can buy from Turbo but had to still drill out the outer sleeve (Radical, DV8 and Big B have very dense cores). As for using the other systems out there I have seen the cracking happen with the Vise system also. Don't drill many Columbia balls but the few lower level balls I have drilled seem to have a very thin cover also.
Thanks Dustin, that is helpful. For the record, I don't think I've ever had any cracking around the finger holes, but of course, they are well-beveled.

Me getting a ball to a pro-shop is problematic so I am looking for a remedy I can do in the garage.

It would be nice if Turbo reps are reading this stuff because I know I am not the only bowler with this problem of not being able to get the IS into or out of the ball. Yes, we have their tools but they aren't enough sometimes. I'm thinking there needs to be a fix to the OS but I don't know what that would be (metal not plastic?). Or perhaps the hole, once drilled and reamed, needs to be enlarged in some manner to allow for a bit of expansion.

In the mean time, my solution is to sand down the outside of the IS.

Again, thanks,

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Re: Circular Cracking

Post by VLe »

For those that have the problem of a snug inner sleeve. Do you know if the hole that is drilled for the outer sleeve is made by using the "official" drill bit provided by Turbo? All of my SG's are drilled with the drill bit provided by turbo and they are more likely being loose than too tight. I have switch grips drilled by 3 different PSO's (different drill bit used in different locations). It is more likely that I have to use some tape on the inside of the outer sleeve to make it more snug (its a must in one ball). Before the OS is glued to the ball, it is possible to check how the sleeve fits to the hole. The outer sleeve can be sanded a little before glueing it to the place to make it stick better and in some cases to make it less snug.

I wonder if a too tight inner sleeve could have effect on the circular cracking problem also. :roll:

And for those cracked finger holes, the lack of beveling was not the case there. The edges were well-rounded.
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Re: Circular Cracking

Post by Viper »

VLe wrote:For those that have the problem of a snug inner sleeve. Do you know if the hole that is drilled for the outer sleeve is made by using the "official" drill bit provided by Turbo? All of my SG's are drilled with the drill bit provided by turbo and they are more likely being loose than too tight. I have switch grips drilled by 3 different PSO's (different drill bit used in different locations). It is more likely that I have to use some tape on the inside of the outer sleeve to make it more snug (its a must in one ball). Before the OS is glued to the ball, it is possible to check how the sleeve fits to the hole. The outer sleeve can be sanded a little before glueing it to the place to make it stick better and in some cases to make it less snug.

I wonder if a too tight inner sleeve could have effect on the circular cracking problem also. :roll:

And for those cracked finger holes, the lack of beveling was not the case there. The edges were well-rounded.
I am not standing there when the hole for the OS is drilled but I use a reputable pro-shop, one I have been using for years, and one which will listen to me if I have a complaint. He assures me, and I believe him, that he is using nothing but spec Turbo products to install the Turbo system, and using exactly the procedure dictated by Turbo.

I mentioned that I have numerous balls with this system all installed by the same guy yet it will vary as to whether or not I have tight fit (or too tight a fit!). So what are the variables? If my driller installs the system the same way every time then I am left to wonder if the plastic pieces themselves are always to spec, and/or it's the composition of the BB that is causing the issue depending on the time of year/season.

You mentioned adding tape to the outside of the IS barrel, yes, I have had the occasion to do so, but that was many years ago.

I will tell you a second observation: The IS with the turbo-installed vinyl slug that the shop operator would drill ALWAYS is too snug. I have two that I have to reduce the circumference of the IS (using sandpaper) IOT get them to function properly. My IS with the glued-in custom slug, that's a crap shoot as to whether that is going to stick or not. Fortunately for me, my very first IS with custom slug is the one I use, and fits perfectly in all of my BBs. It's when I have to go to the back-up or one of the other ones I use if my thumb swells (which is infrequent), that I have the good chance of it sticking. But the one where I over-torqued the slug, breaking it free of the IS, was the worst case I have experienced with the sticking problem.

Still waiting/hoping a Turbo rep will weigh-in here.

Length comment, I apologize. I appreciate your comments.

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Re: Circular Cracking

Post by LittleTiger »

Viper wrote:I mentioned that I have numerous balls with this system all installed by the same guy yet it will vary as to whether or not I have tight fit (or too tight a fit!). So what are the variables? If my driller installs the system the same way every time then I am left to wonder if the plastic pieces themselves are always to spec, and/or it's the composition of the BB that is causing the issue depending on the time of year/season.
Based on what I have discussed with PSOs my understanding is that this issue is caused by high density core on bowling ball.

I have also noticed that I don't have that issue with bowling balls which I have drilled using my cheap drill machine which is more loosen than these expecive ones which PSOs are using. That why hole will be little bit bigger than 1 1/2". Luckily couple of more drops super glue is enough to keep that outer sleeve in ball.


What comes to that circular cracking issue I have also noticed that I have that basically on all bowling balls which are drilled by PSO but none of them which I have drilled myself. So it looks that little bit "too big" hole would help to this issue.
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Re: Circular Cracking

Post by Viper »

LittleTiger wrote: Based on what I have discussed with PSOs my understanding is that this issue is caused by high density core on bowling ball.

I have also noticed that I don't have that issue with bowling balls which I have drilled using my cheap drill machine which is more loosen than these expecive ones which PSOs are using. That why hole will be little bit bigger than 1 1/2". Luckily couple of more drops super glue is enough to keep that outer sleeve in ball.


What comes to that circular cracking issue I have also noticed that I have that basically on all bowling balls which are drilled by PSO but none of them which I have drilled myself. So it looks that little bit "too big" hole would help to this issue.
Little Tiger, I would say you might have a valid point. If I had an accurate and repeatable method to do my own attaching of the OS to the ball, I would ask the driller to just drill the hole using his Turbo bits/reamers and just send me the ball and the OS. I could then work out the hole a bit (that last 1/3 of the hole and then attach the OS.

Thanks,

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Re: Circular Cracking

Post by VLe »

The high density of the core could make the drill bit to wander a little causing the slug to be tight (or loose). Using a dull drill bit makes it worse along with few other points.
Viper wrote:Little Tiger, I would say you might have a valid point. If I had an accurate and repeatable method to do my own attaching of the OS to the ball, I would ask the driller to just drill the hole using his Turbo bits/reamers and just send me the ball and the OS. I could then work out the hole a bit (that last 1/3 of the hole and then attach the OS.
We are talking of very small tolerances here. You can try to fit your inner slug to the outer sleeve before gluing it to the ball. If it feels nicely snug on it, you would want the outer slug to almost drop into the drilled hole. In any case you are able to sand off a little from the outer sleeve by hand if it is a too tight fit. With a correct drill bit and professional PSO this shouldnt be a problem. It is a stupid thing to even think that you would want to finish the drilled hole and glue the slug yourself because the PSO just seem to be lazy here. :o

In my opinion if you get very different results by same PSO there is a problem. The driller should have time and knowledge to make these fittings right. I had one outer sleeve that was so loose that it didn't stay on place with a standard superglue so I ended using a two part epoxy and had no problems since. Now it is the strongest part on that ball.

P.S. The thin and transparent "office tape" is great to put inside outer sleeve to make the loose inner slug more snug. It is always better to fit the outer sleeve to the inner sleeve so you can get it similar with every ball.
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Re: Circular Cracking

Post by Viper »

VLe wrote:The high density of the core could make the drill bit to wander a little causing the slug to be tight (or loose). Using a dull drill bit makes it worse along with few other points.



We are talking of very small tolerances here. You can try to fit your inner slug to the outer sleeve before gluing it to the ball. If it feels nicely snug on it, you would want the outer slug to almost drop into the drilled hole. In any case you are able to sand off a little from the outer sleeve by hand if it is a too tight fit. With a correct drill bit and professional PSO this shouldnt be a problem. It is a stupid thing to even think that you would want to finish the drilled hole and glue the slug yourself because the PSO just seem to be lazy here. :o

In my opinion if you get very different results by same PSO there is a problem. The driller should have time and knowledge to make these fittings right. I had one outer sleeve that was so loose that it didn't stay on place with a standard superglue so I ended using a two part epoxy and had no problems since. Now it is the strongest part on that ball.

P.S. The thin and transparent "office tape" is great to put inside outer sleeve to make the loose inner slug more snug. It is always better to fit the outer sleeve to the inner sleeve so you can get it similar with every ball.
I have used lazy PSOs in the past but this guy is not. I've been emailing the guy about this problem and he told me after the hole is drilled and reamed, he goes in past the coverstock with a bevel sander to open it up a bit. Only thing else I could ask of him is to record a video of what he doing! I don't think my PSO is the problem. This particular ball is roughly five years old and when I was using it I had no problem using the IS. It's only as the ball has aged that this has occurred (on this particular ball). Still not explained is why a drilled Turbo IS with slug is tight when my IS with my custom slug is generally not.

No matter how good someone is, if I can do something myself I will do it. I mount my own finger grips (no big deal), I have mounted my own slugs to my IS so that I have exactly angle I want, I repair my own nicks, scratches, gouges, etc., I refinish my own coverstocks, and I am on the verge of repairing the circular cracking in my Blur. That's just the way I am wired.

Great conversation. Have decided to seek out a friend with a bevel sander and I'm going to work the inside of that OS in the ball where I wedged in the IS.

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Re: Circular Cracking

Post by VLe »

Viper wrote:This particular ball is roughly five years old and when I was using it I had no problem using the IS. It's only as the ball has aged that this has occurred (on this particular ball). Still not explained is why a drilled Turbo IS with slug is tight when my IS with my custom slug is generally not.
Ok, I thought that you had this inconsistency with freshly drilled balls. The same ideology goes with IS. If you fit a snug/tight vinyl slug to it, it will increase the outer diameter of the IS a bit. Therefore your custom thumb slugs are little bit smaller slugs in diameter than those vinyl slugs what turbo uses in their factory. You can try to put those custom IS's to the new unassembled outer sleeve to see how loose fit they are in reference of the factory ones.

You should choose one reference ball and fit all of your IS's to it perfectly either by sanding or adding tape to the IS. The reference ball should be freshly drilled and not modified (sanded) one. Then you have uniform IS's.
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Re: Circular Cracking

Post by Viper »

[quote="VLe"][/quote]

VLe, excellent idea. I am going to give the bevel sander a try on that one ball and if that doesn't do the job then I'm giving it away. I will stick with the custom slugs, too. I just need to decide on that reference ball.

Thanks!

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