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View Full Version : draw shot articles, feedback, and advice



dr_dave
04-13-2006, 01:47 PM
It seems to me that one of the most often discussed topics on this forum is the draw shot. Because of this, I was inspired to write a series of seven articles on draw shot physics, aiming, applications, technique, and drills. The first six articles can be found in the instructional articles section of my website (http://www.engr.colostate.edu/~dga/pool/bd_articles/index.html). The two most recent articles are drafts that have not yet been published. The others have already appeared in Billiards Digest. One reason for my post is that I would like some feedback and/or critique on my most recent article (June, 2006 (http://www.engr.colostate.edu/~dga/pool/bd_articles/june06.pdf)). It presents a framework for a useful (I hope) draw drill. I have a couple of weeks to make changes before the article goes to print, so please let me know if you have any input.

People who have posted questions about draw shots in the past might also find my May, 2006 (http://www.engr.colostate.edu/~dga/pool/bd_articles/may06.pdf) article useful. Some of the information came from my book ("The Illustrated Principles of Pool and Billiards," 2005), but much of it came from stuff I learned participating on this forum. I hope you guys find it useful. I would also like to know if people think I missed any important points or if you think I misrepresented anything.

Thanks for your input,
Dr. Dave

vinnie717
04-14-2006, 06:30 AM
Yeah there is many many articles and posts on the draw shot and IMO it is too many,cmon if u think about it the draw is a simple shot. Hold the cue farther back towards the end,hit the cue ball at the bottom and follow through. Im 14 years old and i have no problem drawing a tables length consistantly. If there is such a big problem with drawing the ball use follow or sumthing. Just dont complain and asking how to draw the cueball,look at previous posts. Sorry if i came off as a hard ass but its jus in my opinion

vince

SpiderMan
04-14-2006, 06:57 AM
<blockquote><font class="small">Quote vinnie717:</font><hr> Yeah there is many many articles and posts on the draw shot and IMO it is too many,cmon if u think about it the draw is a simple shot. Hold the cue farther back towards the end,hit the cue ball at the bottom and follow through. Im 14 years old and i have no problem drawing a tables length consistantly. If there is such a big problem with drawing the ball use follow or sumthing. Just dont complain and asking how to draw the cueball,look at previous posts. Sorry if i came off as a hard ass but its jus in my opinion

vince <hr /></blockquote>

I think it's not a question of being able to draw the ball back the length of the table - I could show anyone how to do that in a matter of minutes.

But if they want to draw it back exactly 18 inches, that is much, much harder. Especially when other variables in the setup are allowed to change. The only good approach is organized practice. I tend to favor the "progressive" drills put forth by Bob and Scott (and other instructors) because the reinforcement of scorekeeping seems to add a lot to your focus and understanding.

SpiderMan

Billy_Bob
04-14-2006, 07:04 AM
<blockquote><font class="small">Quote vinnie717:</font><hr> ...Im 14 years old and i have no problem drawing a tables length consistantly... <hr /></blockquote>

Yea, but can you draw back 1 diamond consistently? If you need to draw the cue ball back 1 diamond and 1/2 diamond will not work and 1 1/2 diamonds will be too far - needs to be exactly 1 diamond of draw.... This is what is hard to do.

I've practiced drawing the cue ball back specific distances like 1 diamond, 2 diamonds, 3, 4, etc. quite a bit.

But now my biggest problem is I don't look at my next shot from the angle I will be shooting it. So I draw back what appears to be correct (Pretty much can do this). Then go to shoot my next shot and find out I should have drawn the ball a bit further back or whatever! Uggghhh! /ccboard/images/graemlins/confused.gif

vinnie717
04-14-2006, 03:37 PM
Ha i feel like an idiot good points good points but to me its sorta like feel, but it is tough thats fer sure..

Jal
04-14-2006, 06:32 PM
<blockquote><font class="small">Quote dr_dave:</font><hr>...I would also like to know if people think I missed any important points or if you think I misrepresented anything.<hr /></blockquote>Hi Dr. Dave,

There are a couple of minor points I'd like to make in reference to your May article.

A couple of weeks ago Cushioncrawler noted that, at least for a cueball which isn't bouncing, the maximum tip offset doesn't always yield the most draw. I've been looking at this and it appears that the most efficient tip offset - the one which requires the least amount of cue speed - is in the range .36R to .73R (while acknowledging that .5R is about the practical limit). The general trend is that the farther the balls are apart and the smaller the maximum cue speed you're willing to employ, the closer this offset is to .36R. You don't get much draw, but you get even less or stun or follow if you hit lower down. So while it's generally true that hitting lower produces more draw, there are exceptions.

For stop/stun shots, the most efficient offset is .36R, and this seems to be true, surprisingly, regardless of how far the balls are apart or the amount of cloth friction. This varies slightly with cue mass, but hardly at all over the range of typical cue weights. Unfortunetly, this isn't necessarily the best offset when the balls are relatively close and you have a choice of hitting low and soft or high and harder. Final spin sensitivity (spin rate at the object ball) goes up with the tip offset. Roughly, it's about twice as much at .36R than at .2R, and about three times as much than at .1R. Similiar numbers apply to draw shots, so it's not clear that hitting lower and slower is always better.

In order to minimize the amount of follow that develops, the most efficient offset is in the range 0R to .36R. Unlike for stop/stun, there is no fixed value for it if you want a certain specific amount of follow or draw action (as opposed to none). It varies with ball separation for both follow and draw.

The .36R figure requires a little adjustment for vertical squirt. For a bouncing ball it's hard to say. While it's relatively easy to predict the amount of spin it loses compared to a sliding ball, the hard part is knowing its initial state after coming off the tip.

Okay, picayune points, but I find them interesting and hopefully they're correct.

Thanks again for making these informative articles available and inviting us to have at them. I was particulary interested in the Coriolis limit of .6R mentioned in your October article, but can't say I understand it.

Jim

pooltchr
04-14-2006, 08:36 PM
<blockquote><font class="small">Quote Billy_Bob:</font><hr> But now my biggest problem is I don't look at my next shot from the angle I will be shooting it. So I draw back what appears to be correct (Pretty much can do this). Then go to shoot my next shot and find out I should have drawn the ball a bit further back or whatever! Uggghhh! /ccboard/images/graemlins/confused.gif <hr /></blockquote>

BillyBob, with all your studying and time spent on the forums, I can't believe you have never heard anyone suggest that one of the keys to a run out is to plan 3 balls at a time...the one you are shooting, the one you need to get shape on, and the one you will be going for after that one....always 3 balls at a time. Only planning your shot and shape on the next ball will get you into the exact problem you described.
Steve

Billy_Bob
04-15-2006, 07:01 AM
<blockquote><font class="small">Quote pooltchr:</font><hr>
BillyBob, with all your studying and time spent on the forums, I can't believe you have never heard anyone suggest that one of the keys to a run out is to plan 3 balls at a time...the one you are shooting, the one you need to get shape on, and the one you will be going for after that one....always 3 balls at a time. <hr /></blockquote>

Oh I'm planning 3 balls ahead and more. Where I get into trouble is I look at my next shot from the *wrong* angle. I'm in a hurry and don't take time to look at my next shot from the angle I will be shooting it.

So I leave the cue ball in what appears to be the correct spot, but when I go to shoot the next shot, I am on the wrong side, or the angle will not be right for the shot after that. And this is a few inches difference usually.

Bit I'm learning to look at my next shot from where I will be shooting it (when cue ball position is critical).

Drop1
04-16-2006, 06:49 PM
Vince,being a hard ass is part of being fourteen,and we have all been there,and done that. I have probably posted more questions about draw,than any person on this forum,and drawing the length of the table seldom comes up. Controling the draws distance is no problem,but drawing the ball back around my opponents ball,can be a problem where I'm not drawing stright back,but arching the return of the cue ball to the left or the right. Sometimes whem the object ball is frozen to the rail, I might send the cue ball towards the center of the table,instead of bring it back. I want to see that guy in Vegas,that makes the eleven rail shot.

Scott Lee
04-17-2006, 07:53 AM
<blockquote><font class="small">Quote Billy_Bob:</font><hr> I'm in a hurry <hr /></blockquote>

...and therein lies the problem (for almost ALL poolplayers). When you get in a hurry playing pool, you get in a hurry to miss, or make an error. This is why specific, well-defined pre-shot routines are SO critical, and why they have to be practiced until they are literally unconscious.

Scott Lee

dr_dave
04-17-2006, 09:00 AM
<blockquote><font class="small">Quote SpiderMan:</font><hr>But if they want to draw it back exactly 18 inches, that is much, much harder. Especially when other variables in the setup are allowed to change. The only good approach is organized practice. I tend to favor the "progressive" drills put forth by Bob and Scott (and other instructors) because the reinforcement of scorekeeping seems to add a lot to your focus and understanding.<hr /></blockquote>
I agree that the progressive practice drills are excellent. If people want to see and print them, they can be found on pages 5-13 of Bob's online clinic document (http://www.sfbilliards.com/basics.pdf). FYI, I have links to these and other drills and resources in the learning and teaching resources section of my website (http://www.engr.colostate.edu/~dga/pool/resources/index.html).

Regards,
Dave

dr_dave
04-17-2006, 11:41 AM
Jim,

Sorry it took me so long to respond. I was out of town for several days.

Regards,
Dave

<blockquote><font class="small">Quote Jal:</font><hr>A couple of weeks ago Cushioncrawler noted that, at least for a cueball which isn't bouncing, the maximum tip offset doesn't always yield the most draw.<hr /></blockquote>
I guess you are assuming constant cue stick speeds and constant distances betweent the CB and OB in your comparison.

<blockquote><font class="small">Quote Jal:</font><hr>I've been looking at this and it appears that the most efficient tip offset - the one which requires the least amount of cue speed - is in the range .36R to .73R (while acknowledging that .5R is about the practical limit).<hr /></blockquote>
Assuming that you have enough cue stick speed to minimize the "drag" losses between the CB and OB (or if the CB and OB distance is small), the optimal is very close to 0.5. Coriolis did a very thorough study of this. My October '05 article (http://www.engr.colostate.edu/~dga/pool/bd_articles/oct05.pdf) has many illustrations, explanations, and high-speed video references backing up this claim. I would be curious to find out how you arrived at the 0.73R number. Coriolis' theory and my experiments have not come close to yielding numbers that high (see the article (http://www.engr.colostate.edu/~dga/pool/bd_articles/oct05.pdf) for details).

<blockquote><font class="small">Quote Jal:</font><hr>The general trend is that the farther the balls are apart and the smaller the maximum cue speed you're willing to employ, the closer this offset is to .36R.<hr /></blockquote>For large distances and controlled cue stick speed, this sounds reasonable. Did you come up with this from experiments or from an analysis?

<blockquote><font class="small">Quote Jal:</font><hr>You don't get much draw, but you get even less or stun or follow if you hit lower down. So while it's generally true that hitting lower produces more draw, there are exceptions.<hr /></blockquote>Good point. For larger distances, you nee more speed. HSV 3.1 (http://www.engr.colostate.edu/~dga/pool/high_speed_videos/HSV3-1.htm) shows a good example of the "drag" or "skid" that occurs with distance and inadequate ball speed. The lower you hit the cue ball (to achieve more spin), the faster you need to stroke the cue stick to create the same CB speed (to limit the "skid" losses).

<blockquote><font class="small">Quote Jal:</font><hr>For stop/stun shots, the most efficient offset is .36R, and this seems to be true, surprisingly, regardless of how far the balls are apart or the amount of cloth friction. This varies slightly with cue mass, but hardly at all over the range of typical cue weights. Unfortunetly, this isn't necessarily the best offset when the balls are relatively close and you have a choice of hitting low and soft or high and harder. Final spin sensitivity (spin rate at the object ball) goes up with the tip offset. Roughly, it's about twice as much at .36R than at .2R, and about three times as much than at .1R. Similiar numbers apply to draw shots, so it's not clear that hitting lower and slower is always better.<hr /></blockquote>
Do you have an analysis you can easily share (e.g., post as a PDF)? I would like to look at this more closely.

<blockquote><font class="small">Quote Jal:</font><hr>Thanks again for making these informative articles available and inviting us to have at them.<hr /></blockquote>
You're very welcome. Thanks for the feedback!

<blockquote><font class="small">Quote Jal:</font><hr>I was particulary interested in the Coriolis limit of .6R mentioned in your October article, but can't say I understand it.<hr /></blockquote>
The full analysis can be read in the recently released English translation of Coriolis' work (http://www.billiardsdigest.com/ccboard/showthreaded.php?Cat=&amp;Board=ccb&amp;Number=217843&amp;page =0&amp;view=collapsed&amp;sb=5&amp;o=&amp;fpart=&amp;vc=).

Regards,
Dave

Scott Lee
04-17-2006, 03:35 PM
Dave...There is a MUCH simpler answer to the question of how low can you go. Place a stripe horizontal to the table. Aim the top edge of your tip at the bottom edge of the stripe. That is as low as you can stroke the CB without miscuing. Numbers like you guys are using are way too confusing, and not really applicable, imo.

Scott Lee

dr_dave
04-17-2006, 03:45 PM
<blockquote><font class="small">Quote Scott Lee:</font><hr>Dave...There is a MUCH simpler answer to the question of how low can you go. Place a stripe horizontal to the table. Aim the top edge of your tip at the bottom edge of the stripe. That is as low as you can stroke the CB without miscuing.<hr /></blockquote>
I agree, for most brands of balls. In fact, I recommend this in my May '06 article (http://www.engr.colostate.edu/~dga/pool/bd_articles/may06.pdf). The Elephant Practice Cue Ball also has a circle indicating the safe limit for off-center hits.

<blockquote><font class="small">Quote Scott Lee:</font><hr>Numbers like you guys are using are way too confusing, and not really applicable, imo.<hr /></blockquote>
I agree that the numbers are not useful for most people, but they do let us quantify things.

Regards,
Dave

wolfdancer
04-17-2006, 04:28 PM
Hey, I once voted Republican, once bedded a sheep, once visited Ala....does any of that count??
now that I think of it, I picked up the sheep in a bar
in Ala. Had to fight off two locals ( republicans) to get her out of there.
Ornery cuss though...do female sheep have horns?

Scott Lee
04-17-2006, 05:25 PM
Dave...The Elephant Balls are good practice tools. Just FYI, if you measure the size of the circle on the Elephant Ball, you will find it is exactly the same size as the white area of the striped ball. Also, the striped ball, turned on it's verical axis, is also representative of how far you can stroke on the edge of the CB, for maximum sidespin...so it works well all ways...for topspin/follow, backspin/draw, and sidespin/english.

Scott Lee

Cornerman
04-18-2006, 05:54 AM
<blockquote><font class="small">Quote Scott Lee:</font><hr> Also, the striped ball, turned on it's verical axis, is also representative of how far you can stroke on the edge of the CB, for maximum sidespin...<hr /></blockquote>Are all stripes the same width? (Considering only the Aramiths and Centennials)

Frd

dr_dave
04-18-2006, 06:06 AM
<blockquote><font class="small">Quote Scott Lee:</font><hr> Dave...The Elephant Balls are good practice tools. Just FYI, if you measure the size of the circle on the Elephant Ball, you will find it is exactly the same size as the white area of the striped ball. Also, the striped ball, turned on it's verical axis, is also representative of how far you can stroke on the edge of the CB, for maximum sidespin...so it works well all ways...for topspin/follow, backspin/draw, and sidespin/english.<hr /></blockquote>
Excellent point; although, I don't think the stripe width is the same for all brands of balls. But it is easy to check with a ruler. The limit for the maximum safe cue tip offset is 0.5R, where R is the radius of a pool ball. Since the diameter of a pool ball is 2 1/4", the maximum safe offset is:

0.5 R = 1/2 [1/2 (2 1/4")] = 1/2 (1 1/8") = 9/16"

This happens to be the radius of the circle of an Elephant practice ball circle. One should use a ruler to verify that the stripe width is 1 1/8" (2 * 9/16") before using a striped ball for practice.

Regards,
Dave

dr_dave
04-21-2006, 09:30 AM
Did anybody try the draw drill in the article (see below)? Any feedback? Did it help you learn anything about your stroke? Any recommendations on how to improve the drill or the post-drill analysis?

Thanks,
Dave

<blockquote><font class="small">Quote dr_dave:</font><hr> It seems to me that one of the most often discussed topics on this forum is the draw shot. Because of this, I was inspired to write a series of seven articles on draw shot physics, aiming, applications, technique, and drills. The first six articles can be found in the instructional articles section of my website (http://www.engr.colostate.edu/~dga/pool/bd_articles/index.html). The two most recent articles are drafts that have not yet been published. The others have already appeared in Billiards Digest. One reason for my post is that I would like some feedback and/or critique on my most recent article (June, 2006 (http://www.engr.colostate.edu/~dga/pool/bd_articles/june06.pdf)). It presents a framework for a useful (I hope) draw drill. I have a couple of weeks to make changes before the article goes to print, so please let me know if you have any input.

People who have posted questions about draw shots in the past might also find my May, 2006 (http://www.engr.colostate.edu/~dga/pool/bd_articles/may06.pdf) article useful. Some of the information came from my book ("The Illustrated Principles of Pool and Billiards," 2005), but much of it came from stuff I learned participating on this forum. I hope you guys find it useful. I would also like to know if people think I missed any important points or if you think I misrepresented anything.

Thanks for your input,
Dr. Dave <hr /></blockquote>

wolfdancer
04-21-2006, 12:25 PM
Dr. Dave, neat drill, and I hope to practice it this weekend.

dr_dave
04-21-2006, 12:37 PM
<blockquote><font class="small">Quote wolfdancer:</font><hr> Dr. Dave, neat drill, and I hope to practice it this weekend.<hr /></blockquote>
I'll look forward to your report and suggestions.

Dave