cue Dr. Dave's answers to frequently-asked questions
(FAQs),
mostly from the BD
CCB and AZB
discussion forums
maintained for the book: The
Illustrated Principles of Pool and Billiards,
the DVD series: The Video Encyclopedia of Pool Shots,
and the monthly Billiards
Digest "Illustrated Principles" instructional articles
For more information, see Disc II of the Video Encyclopedia of Pool Shots
How do you clean and maintain a cue?
Wiping with a damp rag and rubbing dry with a dry rag usually does the trick fairly well, especially if done regularly.
from JoeW:
I have been cleaning cues for many years and have tried many systems because I like a clean stick. About one year ago someone mentioned trying Mr. Clean's Magic Eraser. You can buy these in most any grocery store. I have found there is nothing better to return a cue stick to a like new condition.
Dampen the sponge like Magic Eraser and wipe down the cue including the ferrule. Wipe the excess moisture (there should be very little) and the grime off the cue with a cotton towel.
You can use a dollar bill to burnish the stick if you want to be like the old time pool players.
The best way to slick the cue that I have found is to use an old piece of leather. Could be a piece cut from a belt, the tongue of a shoe or whatever. Soft natural leather is all that is needed.
Wind the leather around the cue and move it as fast as you can up and down the first 18 inches or so. This will heat up and seal the cue. It is almost ready to use.
Wet the edge of the cue tip liberally with saliva and then burnish this with a dollar bill or the back of a piece of emery cloth (that is what I use). This will make the tip look nice but more importantly it will help to harden it and it will be less likely to mushroom.
from Majic:
I smooth the shaft after using the magic eraser and burnish it. I also use a dry film lubricant afterwards and this helps seal as well as provide a slick surface. Some people I know use Rain-X. RZ-50 made by Dupont is a clear product just to mention a couple. If you decide to experiment with other products just be certain is doesn't dry with a white film.
From eb_in_nc:
There's a product on the market called Q-Wiz. It's a double sided pad, the one side for roughing, the other for polishing. It is a high tech micro abrasive that won't burn through the finish and reduce the diameter of the cue. I've been using it for one year and love how it works. It's also washable and reusable.
What effects does cue elevation have on a shot?
When you "jack up" your cue, by raising the butt (back) end, several bad things can happen, including:
However, sometimes cue elevation is required to shoot over an obstacle ball or rail, or to avoid a double hit when there is only a small gap between the CB and OB, or to execute a jump or masse shot. In these cases you often don't have a choice but to elevate.
from Bob Jewett:
from Patrick Johnson:There are some other possible reasons for elevation:
- Easier on the back.
- Can't make a flat bridge for draw.
- Elevation is required on some shots due to obstacles or the cushion. If you choose a substantial, fixed elevation of maybe 12 degrees, you can use that elevation for nearly all shots and you do not need to learn (subconsciously) the adjustments required for lower elevations.
If your stroke isn't very consistent there is some logic to the idea that jacking up a little could help with accuracy. Jacking up increases swerve, which might help to counteract the squirt caused by accidental offcenter hits (especially with a high-squirt cue). Obviously this is a bandaid over a stroke problem that should be fixed, and jacking up is the wrong way to go about it.
"feel," "hit," and "playability"
What is "feel,""hit," and "playability" really mean, and do they affect a shot?
These are qualitative phrases used to describe the shock, vibration, and sound that a player feels and hears during (but mostly after) the cue tip hits the cue ball, especially when the CB is hit off center for English. The feel and sound of a hit are affected by:
There are many physical attributes that contribute to how a cue "plays" and whether or not it is physically comfortable to a player. Here is a partial list:
These things can definitely affect how a cue "plays." Craftsmanship and quality are also important attributes of a cue.
The shock and vibration is felt, and the sound is heard, after the CB is already gone, so they have no direct effect on the outcome of a shot; although, some people claim the "feel" is important to getting good "feedback" on the shot, but not all players place importance on this. To many, what the CB does is "feedback" enough.
A cue's flex or vibration can't have much to do with the physics between the tip and CB during the extremely brief (approximately 0.001 second) impact time. Most of the flex and vibration occurs well after the CB is gone. For example, see:
HSV A.25 - Cue deflection and vibration due to firm stroke with English
and
The vibration affects the "feel" of the cue, but it doesn't have much (if any) effect on the physics between the tip and CB.
Regardless of the physics, there are many "qualitative intangibles" ("feel," "hit," "sound," "aesthetics," etc.) that might be psychologically important to a player even if the characteristics might not have any direct effect on the outcome of a shot.
from rocky:
A stiff cue refers to the taper on the shaft and how much it bends when you shoot with it. A lively cue refers to how much vibration is transmitted through the cue when you hit the cue ball.
What is the purpose for the ferrule?
The main purpose for the ferrule is to protect the wood on the end of the shaft. It allows one to change the tip without damaging the shaft wood, and it might help distribute the impact forces to the shaft during tip impact. The ferrule also affects the look, feel ("hit"), and sound of the cue. A smaller and lighter ferrule results in less squirt (since the ferrule material is typically heavier than wood).
What is different about a
jump cue?
Jump cues are shorter and lighter, with a hard tip (e.g., phenolic). All of these features make it easier to get more rebound height off the table slate with a legal hit.
Can a low-squirt cue help my game?
My December '07 BD article summarizes the results of a poll concerning whether or not a low-squirt shaft helps and who it helps. I present and discuss the results in the article.
I also present a logical analysis with a graphical interpretation to try to explain how a low-squirt shaft can help. The assumptions of the analysis are similar to what Shepard describes in an example in his Everything you Always Wanted to Know About Cue Ball Squirt, but Were Afraid to Ask article.
BTW, here's the last line of the article: my answer to the question of whether a low-squirt shaft can help is: yes, especially if you believe it can help you. The mind is a powerful thing. I use a low-squirt cue and I think I play better with it; therefore, I probably do. I wrote this because the analysis shows only a small expected increase in accuracy with a low-squirt cue for a player with decent squirt knowledge/intuition. Although, a novice player who knows nothing about squirt and how to compensate for it can definitiely benefit (a small amount) from a low-squirt shaft, especially when they use English (intentionally or not). The CB will go closer to where they are aiming. That's usually a good thing. Now, if the tip is aligned center-ball to begin with and the unintentional English is applied with a "swoop" (non straight) stroke, whichever cue has a natural pivot length (or effective pivot length) best matched to the player's bridge length will be the best at reducing the effects of squirt (or combinations of squirt swerve and throw).
Low-squirt shafts might not be good for everybody. Here are what I consider some "down sides" of low-squirt shafts:
- A "low-squirt" cue can be expensive.
- If somebody is used to compensating aim with a higher-squirt cue, it might be difficult to adjust to the lower-squirt cue.
- Some people might not like the "feel" or "sound" or "look" of a low-squirt shaft.
- Some people might not like the taper of some low-squirt shafts, especially if a closed bridge is used.
- A low-squirt shaft might not be as mechanically sound over long-term use (i.e., the shaft end is not as strong and tough).
- If someone hits lots of low-speed English shots, and he or she is used to a higher squirt helping to cancel some or all of the swerve, then he or she might have trouble adjusting to a low-squirt shaft (where more swerve compensation would be required for these shots).
- low-squirt shafts have long "natural pivot lengths," which might not be appropriate for either BHE or FHE. Therefore, there is no simple aim-and-pivot squirt-compensation method ... a "combination" of BHE and FHE will be required. For more info, see my November '07 article.
- If you have a short bridge length, a low squirt cue could result in more directional error (as compared to a regular squirt cue with a shorter pivot length) due to any unintentional pivot during your stroke.
- If you are used to a low-squirt cue, and you find yourself in a place without your cue, where only regular-squirt cues are available, you might not play very well (until you can adjust).
What is the difference between a low-deflection shaft and a low-squirt shaft?
Nothing. They are the same. A low-squirt shaft creates less ("low") cue-ball squirt but actually results in large ("high") cue deflection (because the end of the shaft is lighter and usually more flexible ... so it deflects away from the CB more with an off-center hit). So a "low"-deflection shaft actually has "high" deflection!!!
This is why I and others prefer the term: "low-squirt shaft" because it results in less CB squirt. A "low"-deflection shaft has low CB deflection, but high cue deflection. Also, what the shaft is doing (deflecting) is not important. What the CB is doing is what counts. The CB squirts less with a low-squirt shaft.
Does a low-squirt shaft allow me to put more spin on the cue ball?
Per my September '07 article, a common low-squirt shaft has a squirt angle of about 1.8 degrees at close to maximum tip offset, as compared to 2.5 degrees for a typical regular-squirt cue. So a low-squirt shaft offers only about 30% less squirt than a typical regular-squirt cue.
Per TP B.7, if you calculate the effective offsets using the squirt angles above, the percentage change in effective tip offset and the resulting spin is 2-3%, so a low-squirt shaft does not give you much gain in spin-generating capability.
Now, when comparing cues and/or tips, it is important that the actual tip offset is the same for both. If the tip size and shape are different, and one uses "tips of English" as a measure, perceived tip offset can be very different than actual offset, resulting in significant differences in the amount of spin. See my January '08 and July '06 articles for illustrations and more information.
What is different about a masse cue?
Masse cues are typically shorter, heavier, and stiffer, and typically have a larger shaft diameter and tip. The shorter length is to improve handling and reduce overhead clearance problems. The extra strength and stiffness are for durability and better action. The extra weight can also help you get more action with less effort.
How do I determine the natural pivot length for my shaft, and why should I?
My November '07 BD article explains and illustrates back-hand English (BHE), front-hand English (FHE), a cue's natural pivot length, and advice for selecting a break cue. Here's a procedure recommended by Colin Colenso for measuring natural pivot length:
Place OB about 6 inches from a corner pocket. Align CB in a straight line with this about 5-6 feet away. Align to pot straight, pivot and hit the shot near maximum speed to ensure insignificant swerve. Adjust bridge length until you consistently have the CB hitting pretty much at the original aim.
It's pretty obvious when you're hitting this shot within 1/10th inch of center which allows you to narrow down the intrinsic pivot point to less than an inch. The CB would spin on the spot if the OB was hit about 1/20th inch off center. This is plenty of accuracy over 5-6 feet. Pretty much as accurate as one could hope to aim the initial pot.
My November '07 BD article also presents a simple procedure for measuring the natural pivot length for a cue; although, throw is more of a factor in these measurements. The procedure in the article yields more of an "effective pivot length," which compensates for both squirt and throw.
TP B.1 uses physics and math to predict the natural pivot length for a cue from squirt angle measurements. Here are some of the conclusions supported by the analysis:
- Squirt angle varies nearly linearly with tip offset, and tip offset varies nearly linearly with cue pivot angle. This is what makes the BHE and FHE methods effective, provided swerve and throw are also taken into consideration.
- A cue's natural pivot length does vary a little with both tip offset and tip shape (radius), so when comparing different cues with experimental measurements, it is important to use the same tip shape and the same amount of tip offset (English) for each cue.
- Cue pivot lengths reported by Platinum Billiards seem to be a little low. They report a range from 8 inches (for a "high-squirt" cue) to 14 inches (for a "low-squirt" cue). Although, numbers from Colin's procedure (see above) seem to back up this lower range.
- Expected cue pivot lengths reported in Ron Shepard's 2001 paper "Everything you Always Wanted to Know About Cue Ball Squirt, but Were Afraid to Ask" appear to be much too large. He reports a range from 10 inches (for a "high-squirt" cue) to 50 inches (for a "low-squirt" cue).
Is there a pivot point for a cue that will compensate for throw and/or swerve in addition to squirt?
Unfortunately, the amount of throw varies with cut angle, shot speed, type of English, amount of topspin or bottom-spin, and ball conditions (for more info, see my August '06 through July '07 articles). Also, swerve depends on shot speed, shot distance, cue elevation, amount and type of English/roll, and ball/cloth conditions (for more info, see my March '08 and April '08 articles). Therefore, it is difficult to predict a required cue pivot point to compensate for anything more than squirt. Maybe this could be done for medium speed shots, at medium distances, with a medium amount of English (with a consistent amount of draw or follow); but otherwise, aim-and-pivot aim compensation alone is not adequate to account for all of the subtleties associated with swerve and throw (see the 2nd Q&A here). Having said all of that, aim-and-pivot methods (e.g., BHE and/or FHE) can still be very helpful to many players on many shots.
How much deflection does a cue of given pivot length produce?
from Patrick Johnson:
MEASURING PIVOT LENGTH:
A shaft's pivot length is the distance the CB travels to be offline exactly the amount of sideways tip offset. It's different for different shafts, but for each shaft there's one pivot length for all tip offsets. The example in the picture assumes a pivot length of 1 diamond (12.5 inches) for illustration purposes.
ADJUSTING FOR SQUIRT:
Pivoting your shaft at its pivot length (pivot point) to apply sidespin makes the shaft duplicate the CB squirt angle in the opposite direction, adjusting for squirt to send the CB along the original shot line.
Find your cue's pivot point, pivot there, make shots/get shape. Simple, right? Well, except for swerve, which changes the "effective pivot point" for every shot.
"squirt," "deflection," "stiffness"
How is cue deflection related to ball squirt?
These terms can be confusing and misleading. Here's my summary:
"low deflection shaft" =
"low
cue ball deflection shaft" =
"low squirt shaft" =
"low
end-mass" shaft =
flexible (AKA "whippy", compliant, not stiff,
"like a wet noodle") shaft end =
large cue shaft flex (i.e., "high
deflection" of cue tip) with an off-center hit
I also prefer the term "squirt" over "cue ball deflection." I certainly prefer "low squirt cue" over "low deflection cue" (because of the ambiguous meaning of "deflection"). I also prefer "small" instead of "low" because that can also be ambiguous. Although, it's not easy to change the terminology people use when it is so ingrained. As long as people are clear, it really doesn't matter. When I hear "low deflection cue," I just assume the implication is "small squirt shaft."
from rocky:
A stiff cue refers to the taper on the shaft and how much it bends when you shoot with it. A lively cue refers to how much vibration is transmitted through the cue when you hit the cue ball.
What is different about the different types of cues and shaft tapers?
Schuler has a good webpage describing the various types of and reasons for typical shaft tapers.
From Snapshot9:
Cues can up to a 14mm tip, and lots of Break/Jump cues, or Break cues, or Jump cues have a 14mm tip because a bigger tip is better for Breaking and/or Jumping. Break cues commonly have a Conical taper (also called European) for added stiffness.
A Break/Jump cue is one that is used for Breaking and Jumping with part of butt coming off so that the shorter Jump portion can be used. Jump cues/portions are commonly
40" long, the minimum length they can be.Leather tips are better for control, but Phenolic tips, which are harder, are better for power and/or lift when jumping. I have a J&J Break/Jump cue with a phenolic ferrule/tip combination that I like a lot, and they can be bought for $60/65 dollars. I used to believe in separate Break cue and jump cue, but the J&J Break/jump changed my mind about that, and a Break/jump combo takes up less space in your case. Phenolic tips do some getting used to though, and almost require a center ball hit.
A standard taper started out 8-10"
A pro taper started out 10-13", now is 13-15"
An European taper is like a long cone shape, with no part of the shaft being the same diameter at any 2 points. (constantly tapers down to the tip).
There is also a straight taper, which a lot of Snooker cues have.
What is the best weight for a cue?
For you main playing cue, use whatever weight feels most comfortable. A heavier cue might be easier for some to keep on line during the stroke, but this is a very individual thing. Now, for the break shot, your optimal weight (for maximum cue ball speed) will depend on your muscle physiology (e.g., fast-twitch vs. slow-twitch muscle fiber dominance). The only way to find out the optimal weight for sure is to experiment.
From pooltchr:
1. I believe the best weight for any player is the weight that feels most comfortable for all types of shots.
2. I believe that different weights can produce slightly different results, but those differences are so slight that most good players can adapt their stroke to get the desired results regardless of the chosen weight.
3. While a long draw shot does require more speed than a shorter one (adjusting speed and or spin is the only way to control draw)we still don't need to use maximum (break) speed even for maximum draw. For that reason, I think any good player can get the required speed with any weight cue. Those same players would be able to adjust their stroke to compensate for the weight differences in various cues.
4. Since over the course of a game, a player will need to vary speed and spin from shot to shot, the most comfortable weight to the individual player makes the most sense to me. It's easier to make slight adjustments to speed and spin with a well balanced comfortable cue. You can establish a centergistic or reference point for a stroke speed follow shot, then work from there to know what is needed when you need to do something else with the cue ball.
