Ferrule material and deflection

[Blue Hog ridr]

I'm thinkin, 6 to 7 " sounds pretty dangerous to me.

The only custom, non Pred or OB ferruless shaft that I had was bored 3".

3" bore. No ferrule. Tip pad. 30" shaft. Played very well.

It Hit a Ton, and played Lights Out, man. Not really, cause I was on the other end of it.

 

[dr_dave]

Dr. Dave's video here estimate no squirt influence past 6 to 8 inches from the tip: http://billiards.colostate.edu/normal_videos/new/NVB-32.htm

I'm not aware of it being proved, but I've assumed the effect of an mass diminishes in proportion to the distance from the tip and hence, a 1mm thickening of the shaft from ferrule to 6 inches back would produce negligible additional squirt. Perhaps the equivalent of a 0.1mm reduction of tip diameter.

It would be interesting if such tests could be done accurately, such that aspects like conical tapering and shaft stiffness influences could be quantified.

Colin,

FYI, I have done tests that clearly show how mass at different distances from the tip affects squirt (cue ball deflection). The results are shown in Diagram 4 in: "Squirt - Part VII: cue test machine results" (February, 2008).

Regards,
Dave

 

[Shawn Armstrong]

All good up until your last paragraph. Here is where your logic breaks down. If you want to learn something, imagine this: Suppose you have two identical shafts, same material, taper, diameter, etc. The ONLY difference is one has a 1" ferrule made of wood like OB's, the other has Ivory. Now, chop off the last 6 inches of both shafts at the tip end. Weigh those two pieces. What do you *think* will be the difference? I think most everyone recognizes that the ivory ferruled shaft section will be heavier. How much heavier? Say a typical shaft is 4 oz, and 29 inches. To keep it really simple, lets say that the 6" piece of the shaft is about 20% of the weight, or 0.83 oz. This is 23.45 grams. This means if the difference in mass is only 2.35 *grams*, then you have a 10 percent reduction in end mass. How much do you think a ferrule weighs?

Seriously, you are wrong. Very wrong. There are few things more interesting to me than watching someone who is wrong, but believes they are right, trying to argue their point, rather than learn something.

Your "help", being very misinformed, is actually offering no help, except in so much as it elicited feedback from others who corrected and clarified the info.

KMRUNOUT

Fresh off my scale, sparky - a one inch ivorine 3 ferrule weighs 3 grams. A thermoset plastic ferrule weighs 2. A wooden ferrule was 2 grams. So, let's add that massive 1 gram difference to that calculation. Seeing as the ferrule is the only variable, and he mentioned an ivorine ferrule, the weight difference is about 1 gram. In your calculation, that works out to a whopping 4% change in deflection.

But feel free to correct me again.

 

[dr_dave]

Fresh off my scale, sparky - a one inch ivorine 3 ferrule weighs 3 grams. A thermoset plastic ferrule weighs 2. A wooden ferrule was 2 grams. So, let's add that massive 1 gram difference to that calculation. Seeing as the ferrule is the only variable, and he mentioned an ivorine ferrule, the weight difference is about 1 gram.

Shawn,

Check out n Diagram 4 in: "Squirt - Part VII: cue test machine results" (February, 2008). A 1 gram difference close to tip makes a bigger difference than you might think.

Regards,
Dave

 

[mjantti]

Shawn,

Check out n Diagram 4 in: "Squirt - Part VII: cue test machine results" (February, 2008). A 1 gram difference close to tip makes a bigger difference than you might think.

Regards,
Dave

Good share. Very good article!
It's excellent when someone has actual real data to back up his theories. Dr. Dave has done priceless job in busting some of the myths concerning squirt. Tap tap tap! :thumbup:

 

[Shawn Armstrong]

Shawn,

Check out n Diagram 4 in: "Squirt - Part VII: cue test machine results" (February, 2008). A 1 gram difference close to tip makes a bigger difference than you might think.

Regards,
Dave

The fact that the study doesn't take into account an object ball, or throw resulting from spin on the cueball, the study means nothing in judging effective cueball deflection, and its effect on the playability of a cue.

 

[Blue Hog ridr]

I would like to see how a short 3 gram ferrule, made from Stainless steel would play.

Different materials of the same weight, different lengths obviously.

How would they play?

Bob Dzuriky makes a custom shaft with a graphite core. Others have made shafts with different cores. Or are we getting into a totally different animal, once we start talking about 3 different types of splices and cores.

Preds pie splice. OB's splice and Meucci's flat lamination.

What about Meucci's 1 1/2 " ferrule.

 

[dr_dave]

The fact that the study doesn't take into account an object ball, or throw resulting from spin on the cueball, the study means nothing in judging effective cueball deflection, and its effect on the playability of a cue.

Wow! You're a tough skeptic!

FYI, the experiment was specifically designed so it would measure only the effects related to shaft properties. Swerve and throw depend on many things that have nothing to do with the shaft (cloth type and condition, ball properties and condition, shot speed and distance, etc.). For more information on why this is the most appropriate way to test shafts, see the squirt (cue ball deflection) robotics testing resource page.

Regards
Dave

 

[rhatten]

Cut the ferrule off, bore the tip end of the shaft about 6 inches, fill the hole with spray foam put on a wood ferrule.

This ^^^^^^ (w/ or w/o foam), also best feel etc... use a a break/jump cue when appropriate.

R

 

[dr_dave]

I would like to see how a short 3 gram ferrule, made from Stainless steel would play.

The "hit" would probably sound and feel different, but if the ferrule weight and everything else were the same, the amount of squirt (cue ball deflection) should be no different, based on what causes squirt.

Although, since steel is so much denser, something else would need to be different for the weight to be the same.

Regards,
Dave

 

[Mitchxout]

I think you may get a better response and feedback from the "Ask the Cuemaker" section.

Depends on their mood. Lol

 

[Blue Hog ridr]

Depends on their mood. Lol

Actually depends as to whether the same question has been asked 1000 times previously.

Which it has.

So, that is proportional to the amount of responses one may get.

You can only ask: How do you make a Milk Dud so many times before someone will suggest using the Search Feature.

 

[Shawn Armstrong]

Wow! You're a tough skeptic!

FYI, the experiment was specifically designed so it would measure only the effects related to shaft properties. Swerve and throw depend on many things that have nothing to do with the shaft (cloth type and condition, ball properties and condition, shot speed and distance, etc.). For more information on why this is the most appropriate way to test shafts, see the squirt (cue ball deflection) robotics testing resource page.

Regards
Dave

Too many variables in the experiment, honestly. No one is going to clip a weight to a shaft in actual play. And the weight, when added, was at a specific location. Different ferrule materials have different stiffnesses that need to be accounted for, in this discussion.

Years ago, I was working a pro event in Canada. Martin Daigle broke the ferrule on his BK that day, at the end of a match. He ran it over to me on the lathe, and asked me to fix it for his next game. I had worked on BKs before, and knew about their ferrules and inherent weakness. So I cut an ivorine ferrule with a large bore, and fit it onto his shaft. I then put a fibre wafer on the end, drilled it out, and installed a stemmed phenolic tip onto the cue. He used it the rest of the tournament. Alain Martel and his entire entourage were testing the cue on a table. They said it didn't deflect any more than an original BK with the softer ferrule. I checked it out. I couldn't tell a difference, either.

The experiment is cool. I'd have liked to have seen the actual shaft changed in such a way that would represent a real life cue - test with soft ferrule. Take average of 100 shots. Change to a phenolic ferrule - do the same. Change to ivory - do the same. Same for drilled out shafts. And come to a conclusion from that.

Not a skeptic. I was a math and stats major, that used to crunch numbers for researchers at a university. I need to see more data, and a much more tightly controlled experiment before I could call the results definitive.

 

[Blue Hog ridr]

That sounds like you did a spur of the moment quick change of the shaft layout Shawn.

Good thinking on that one. Pretty good work for a tourney lathe.

How's the weather been holding out East?

 

[bdorman]

I have a shaft which I believe has a full length Ivorine ferrule. This shaft deflects the ball more than any I've ever tried, but it does hit very solid, which I guess is what the cuemaker was going for.

Question 1: Could I reduce the deflection noticably by changing the ferrule material only, with the same length?

Question 2: Would cutting the ferrule length down to a minimum be a better solution (I know I'd loose some length, but it might be worth the trade-off)?

Have anyone ever tried any of the above options? I believe Ivorine is one of the heavier ferrule materials, which is why I ask. I probably won't do it anyway, but I thought the idea is worth discussing.

Hit center ball.

Problem solved.

Invoice in the mail.

 

[Patrick Johnson]

..........

 

[dr_dave]

The experiment is cool. I'd have liked to have seen the actual shaft changed in such a way that would represent a real life cue - test with soft ferrule. Take average of 100 shots. Change to a phenolic ferrule - do the same. Change to ivory - do the same. Same for drilled out shafts. And come to a conclusion from that.

Agreed. It would be interesting to do more experiments that test all possible variables. I suspect the results would agree with the results of all other experiments done to date: when you reduce the endmass of a shaft, squirt (cue ball deflection) decreases (more so when the weight reduction is closer to the tip).

Regards,
Dave

 

[Shawn Armstrong]

That sounds like you did a spur of the moment quick change of the shaft layout Shawn.

Good thinking on that one. Pretty good work for a tourney lathe.

How's the weather been holding out East?

Tons of snow. Been a pretty white winter so far.

My travel lathe is a 6' that I modified using a Taig mini lathe. Works pretty good. Similar to one of Hightower's Cuesmith lathes, but mine has a few more tricks up its sleeve.

I had done that repair on BKs before. I have never had to do it between sets before, completing the task in 20 minutes. But that was fun