Big table/Small room-thinking outside of the (bar)box

[Monti]

I’m posting this on behalf of my buddy, he hasn’t got his approval to post yet- I guess admin are too busy playing pool and that’s the way it should be!

....If I may I’d like to throw the problem into the forum and see if it elicits any new ideas or pitfalls that I didn’t think of. I’m half way through the project
already and of course I think my solution is the greatest solution ever devised. However, I’m 56 and have learned recently that there are people out there way
smarter than me (don’t ask about my mailbox key fiasco).

Background:
I play in a league with 9’ tables so I wanted a 9’ table in my basement. I only have 11’8” on the long rail sides so technically this isn’t enough clearance for even a 7’ table with a standard 58” cue.
So……. I went ahead and bought an 8’ table, telling myself that I would just use a shorty cue for the occasional shot. Well 40% of my shots required the shorty cue and within a
few days I decided to just move the cue ball by hand away from the rail. This of course negated any concept of positional play and I quickly found myself losing interest.

Then Covid shut us down and I had time to stare off into space and think a bit more about the problem. I could buy a smaller table (loser), buy a new house (nope), knock out a wall (What would the wife say?)
or build a device that could move the table into position depending on the leave of the cue ball. Obviously somebody on YouTube would have already designed such a thing so I cracked a beer and started searching.
Apparently this problem/solution is the only video NOT on YouTube. (teaser: we’ll fix that).

So, staring at the ceiling one night I summarized the following.


The solution needs to be integrated into the normal flow of the game. Ideally, you should forget that the table moves after a few games and just play as if it were a normal table.
This means that manually moving the table is not even being considered. That would affect the flow of the game and introduce human error into the equation (think mailbox key).



1: I need the table to move 12” left or right in order to have unimpeded play. Total linear motion then is 24”.

2: Table need to move into its new location in under 10 seconds. I chose 10 seconds because that’s the approximate time it takes from the instant
I hit the ball until I’m ready to bend over for my next shot. This includes pre-shot routine, staying down after the shot etc.

3: Table need to remain level at all times. My table is leveled now for the centre position. Will it still be level if it’s moved 12” away?

4: The balls can’t move at all. I know my buddy will call me out for cheating if the balls move even the slightest bit. He’ll say they always move in my favor when its my shot and against him when its his shot.
This probably would not have been a problem with the shag carpet that was originally on the table but we changed the cloth for a Simonis worsted cloth a few months back.
The friction coefficient is now VERY low and the balls can easily be disturbed.

5: Braking system: I weigh 200lbs. A rudimentary test with a scale between my belly and the table shows that I apply 15lbs of lateral force on the table when I’m stretched out over the table for an awkward shot.
Table needs to have the equivalent of an emergency brake applied when stopped.

6: Height: My table is 32” high. If I add some sort of mechanism under the table and raise the table X inches I’ll need to be able to lower the table by the same amount.

7: Control activation System: It seems obvious at this point that we are talking about some sort of electric linear actuator. How would it be activated?
Interrupt buttons, Hey Alexa MOVE TABLE LEFT, clapping, IR or Bluetooth remote control, etc. However its done it must not interfere with the flow of the game.

8: Noise: I don’t want the table to be heard over the background music. Mostly Burton Cummins and Gordon Lightfoot at the moment.

9: Lighting: My overhead lights are directly over my table. Lighting needs to be good wherever the table is parked.

10: Safety: A rogue motor powerful enough to move a 600 lbs table could wreak havoc on a table frame. Finished product needs to have safety features build in. E.g. Limit switch/homing sensor of some soft.


So, that’s the scope of the project. I purposely left out all my ideas because I wanted my fellow pool playing buddies (or just nerds as my kids keep telling me) to chime in with some ideas.
My current timeline will have the project completed in about 4 weeks. At that time I will post a “How To Video”. If you have a solution for any of the 10 listed problems then throw it in the mix. It’s not too late for me to change course.



Scott

 

[Good Sam]

Your post reminded me of this video.

Obviously, different direction, but similar idea.

 

[AF pool guy]

Redirect Notice

Maybe something like the self leveling pool table from a cruise ship.


Sent from my iPhone using Tapatalk

 

[NevadaP]

I think you are embarking on a frustrating exercise which will end with less than satisfactory results. The tone of your post suggests that you are determined to move forward with your plan, so I won't waste much time trying to discourage you, but I'd like to do so all the same.

You have an unplayable table now due to room size limitations. I suspect, (predict) that you are headed toward a time consuming and likely costly exercise which will leave you with an unplayable table due to it not being level at any position. Remember that it only requires a few thousandths of an inch in any spot for the table to play 'unlevel'.

For me, and uneven table is just as frustrating as having to play with a short cue, and I have refused to design my pool rooms so that a short cue is needed ( I don't own one).

If the house is designed so that removing or moving a wall is an option at all, I'd be looking at a way to do that first. In the end, it would likely be a less expensive and less frustrating exercise and is likely to end in a much better result.

I can't wait to see what you come up with. And I admire anyone who is so determined to have a table to play on!
NP

 

[HNTFSH]

Ask justnum

 

[straightline]

Your post reminded me of this video.

Obviously, different direction, but similar idea.

"Alexa, pool...

...Right now bitch!"

I've always thought there should be an apron around the table that would provide the player variance in elevation.

 

[Bob Jewett]

I could swear that someone mentioned a table on rails just a little while ago.

Obviously, you need a vision system that can identify the cue ball and move the table to put it as close as possible to the center of the room. It should avoid running over the players (until the bet is right). Rails sound alike a good solution especially if the table only needs to move side-to-side. You don't actually need wheels as rollers should work for this.

 

[noMoreSchon]

I could swear that someone mentioned a table on rails just a little while ago.

Obviously, you need a vision system that can identify the cue ball and move the table to put it as close as possible to the center of the room. It should avoid running over the players (until the bet is right). Rails sound alike a good solution especially if the table only needs to move side-to-side. You don't actually need wheels as rollers should work for this.

I quickly came up with a 'Lazy Susan' type system, where all four legs are at a 12 o'clock position for the center of the room, and all rotate in tandem to push it to one wall or the other. But rails seem so much better now...

 

[Black-Balled]

There's an industrial filing system called a magic aisle. My buddy has a company that puts em in an takes em out...

They require a flooring into which the cabinets sit and the rows of shelves can be rolled against and apart to enable many more cabinets to fit in a given space than static mounted shelving.

Imo, would be easier to enlarge the room or build a freestanding room.

 

[Black-Balled]

Oh...and the cabinets move by rotating a gear/ chain system. The pic show manual method but there is an electric version too that has optic sensors between rows so nobody (nobody else!) gets crushed.

The floor sits about 4" above ground level
.

 

[boogieman]

I'm in agreement with @NevadaP if possible removing a wall would be cheaper and less frustrating.

 

[Bob Jewett]

If the table is on rails or rollers, it probably shouldn't depend on them for the level. The table could be lifted a quarter inch while in transit and then lowered onto adjustable foot plates placed under the usual feet or under special, more solid feet.

 

[Monti]

I'm in agreement with @NevadaP if possible removing a wall would be cheaper and less frustrating.

Hi Guys

thanks for all the replies. Scott will start responding once his application gets approved but I will just add one comment
For those saying removing a wall is the easiest option, well I have met his wife and you haven’t ,so “a moving table it is”

 

[Black-Balled]

Hi Guys

thanks for all the replies. Scott will start responding once his application gets approved but I will just add one comment
For those saying removing a wall is the easiest option, well I have met his wife and you haven’t ,so “a moving table it is”

Right...but she will be ok with him spending a silly amount of money to devise a half assed and potentially dangerous system that might ruin the table for any other different (location) use...all while adding 0 value to the home?

Is she hot?

 

[iusedtoberich]

Well I give you credit for having an original post idea on these forums!

Your friend's project sounds fascinating to me. I fool around with CNC machines on a hobby level. Here is what I would recommend:

-Put the table on linear bearings used for CNC milling machines. You can get them on eBay, or cheaper on aliexpress if you don't mind the 2 month delivery. I think you will need 25mm to 30mm wide linear bearing guides. The wider they are, the more weight they can support, but the more expensive they become.
-Put the guides on the floor, and the trucks on the table legs.
-The guides must be level and on a rigid surface, so when the table moves, it will retain its level.
-Put the guides in a recess in the floor, so that you won't trip over them, and you won't make the table much higher. (side note, if you are tall, a taller table won't be a problem. I have my table on top of 5" blocks and love the height. I'm 6' 3" tall).
-Use a ball screw to move the table. One on each pair of legs. You are only moving a frictional load, not a weight bearing load, so the screws can be on the small side (and cheap side). A 12mm or 15mm screw will be plenty. The larger the diameter the screw, the more expensive. Get the screws from aliexpress or eBay.
-Use a servo motor, not a stepper motor. The prices are almost the same now in the hobby world. A stepper motor will make a horrible ringing noise, especially at the low RPM needed for this application. A servo motor will be whisper quiet. JMC Servo motor is the cheapest. The model number you want is iHSVxx. where the xx is 57 or 60 depending on the size. But technic clearpath servo motors are easier to setup, and still cheap. If you use a belt reduction, a nema 23 size will be fine to move the table, as my educated guess. With no reduction, you might want a nema 34. I'd probably try a nema 23 to start as they are more compact, even without a belt reduction. Actually I take this back. I'd go with a nema 23, and design in a belt reduction. Servos work best at faster speeds (opposite of steppers), so having a belt reduction will mean the servo can spin in an rpm range that has more torque. This will give you more reliable service.
-With a ball screw, (and the servo's not physically attached), you will be able to back drive the screw. This means if you lean on the table, it will turn the ball nut because the friction in the ball screw and ball nut is so low. In comparison, if you used an acme screw or a v-thread screw, the table will be locked in place when you lean on it, even with no servo motor attached. That is an advantage in your situation, at the expense of significantly more friction in the system, and then a more powerful motor needed to turn it. Having used both v-thread leadscrews and ball screws, the difference is huge, and I think I'd still go with a ball screw in your application. With the system on, the servo will hold the table when you lean on it. But if the system is off, the table will move if you lean on it. There are also servo motors that have a break, so that when the system is off, they don't spin. That would also solve this back driving issue.
-You will need this whole system times two. One for each pair of legs. To couple them, tie the two servos together electronically. The other way to do it is use one servo motor and tie both halves together with a belt or a chain. Both methods are used in CNC machines, particularly cnc gantry routers. For your application, the electronic method will be much better, since you won't need a long mechanical system in-between the two sets of legs.
-Have a home and limit switch on the end of each rail.
-For deciding when to move the table, some sort of vision system like Bob mentioned would be nice, but I think that would be way to difficult to implement, unless your guy is an electrical engineer, and computer programmer, and does vision systems for his day job, and can take home the equipment needed from the dayjob. I think a simple button on the table rail that moved the table from one extreme to the other would be simple to do, and easy to operate. You could have it duplicated on both sides of the table. Push it once, and the table moves 24" from where it is. Push it again, and it moves 24" back. That's it. No other options. Nothing to think about. With the ballscrew and linear rails, I don't think it would be a problem to move it 24" in 10 seconds.
-Expect this project to a year to complete in a hobby situation. Unless your guy is very familiar with cnc, CAD, electronics, computers, arduino, etc. Each component in this type of system has a very steep learning curve.

Good luck

 

[HNTFSH]

Right...but she will be ok with him spending a silly amount of money to devise a half assed and potentially dangerous system that might ruin the table for any other different (location) use...all while adding 0 value to the home?

Is she hot?

The hot ones never go for dorks unless............they are rich dorks.

 

[Island Drive]

I’m posting this on behalf of my buddy, he hasn’t got his approval to post yet- I guess admin are too busy playing pool and that’s the way it should be!

....If I may I’d like to throw the problem into the forum and see if it elicits any new ideas or pitfalls that I didn’t think of. I’m half way through the project
already and of course I think my solution is the greatest solution ever devised. However, I’m 56 and have learned recently that there are people out there way
smarter than me (don’t ask about my mailbox key fiasco).

Background:
I play in a league with 9’ tables so I wanted a 9’ table in my basement. I only have 11’8” on the long rail sides so technically this isn’t enough clearance for even a 7’ table with a standard 58” cue.
So……. I went ahead and bought an 8’ table, telling myself that I would just use a shorty cue for the occasional shot. Well 40% of my shots required the shorty cue and within a
few days I decided to just move the cue ball by hand away from the rail. This of course negated any concept of positional play and I quickly found myself losing interest.

Then Covid shut us down and I had time to stare off into space and think a bit more about the problem. I could buy a smaller table (loser), buy a new house (nope), knock out a wall (What would the wife say?)
or build a device that could move the table into position depending on the leave of the cue ball. Obviously somebody on YouTube would have already designed such a thing so I cracked a beer and started searching.
Apparently this problem/solution is the only video NOT on YouTube. (teaser: we’ll fix that).

So, staring at the ceiling one night I summarized the following.


The solution needs to be integrated into the normal flow of the game. Ideally, you should forget that the table moves after a few games and just play as if it were a normal table.
This means that manually moving the table is not even being considered. That would affect the flow of the game and introduce human error into the equation (think mailbox key).



1: I need the table to move 12” left or right in order to have unimpeded play. Total linear motion then is 24”.

2: Table need to move into its new location in under 10 seconds. I chose 10 seconds because that’s the approximate time it takes from the instant
I hit the ball until I’m ready to bend over for my next shot. This includes pre-shot routine, staying down after the shot etc.

3: Table need to remain level at all times. My table is leveled now for the centre position. Will it still be level if it’s moved 12” away?

4: The balls can’t move at all. I know my buddy will call me out for cheating if the balls move even the slightest bit. He’ll say they always move in my favor when its my shot and against him when its his shot.
This probably would not have been a problem with the shag carpet that was originally on the table but we changed the cloth for a Simonis worsted cloth a few months back.
The friction coefficient is now VERY low and the balls can easily be disturbed.

5: Braking system: I weigh 200lbs. A rudimentary test with a scale between my belly and the table shows that I apply 15lbs of lateral force on the table when I’m stretched out over the table for an awkward shot.
Table needs to have the equivalent of an emergency brake applied when stopped.

6: Height: My table is 32” high. If I add some sort of mechanism under the table and raise the table X inches I’ll need to be able to lower the table by the same amount.

7: Control activation System: It seems obvious at this point that we are talking about some sort of electric linear actuator. How would it be activated?
Interrupt buttons, Hey Alexa MOVE TABLE LEFT, clapping, IR or Bluetooth remote control, etc. However its done it must not interfere with the flow of the game.

8: Noise: I don’t want the table to be heard over the background music. Mostly Burton Cummins and Gordon Lightfoot at the moment.

9: Lighting: My overhead lights are directly over my table. Lighting needs to be good wherever the table is parked.

10: Safety: A rogue motor powerful enough to move a 600 lbs table could wreak havoc on a table frame. Finished product needs to have safety features build in. E.g. Limit switch/homing sensor of some soft.


So, that’s the scope of the project. I purposely left out all my ideas because I wanted my fellow pool playing buddies (or just nerds as my kids keep telling me) to chime in with some ideas.
My current timeline will have the project completed in about 4 weeks. At that time I will post a “How To Video”. If you have a solution for any of the 10 listed problems then throw it in the mix. It’s not too late for me to change course.



Scott

What your attempting to do is similar to.
Driving your car with the space saver spare on one wheel, and leaving the other full size tires on the remaining 3 rims.
Eventually this moment in time will pass and your final decision will become clearer by the day, hr week and mileage.

 

[SBC]

Aren't the balls going to move when the table is moving?

Tear out the wall...the wife will adjust!

 

[Black-Balled]

Aren't the balls going to move when the table is moving?

Tear out the wall...the wife will adjust!

I wouldn't thing they'd have to, if the movement was smooth...but is seems like a HUGELY complicated solution to a relatively simple problem.

And opening the room up or creating additional sq ft adds value to the home.

 

[The_JV]

Aren't the balls going to move when the table is moving?

Probably not, but they'll move when the table starts and stops... It really boils down to whether you perfer the novelty of a moving table or want to play the game in an intense manner. Having the balls shift at all changes the game.

In my other life I program large scale material transfer systems. We manuver heavy fabrications on linear rails (etc) with servos. Speaking from a ton of experience, the combination of the ridiculously slow rate of speed and the accel/decel rate that would prevent the balls from shifting would make the game wildly unenjoyable.

Not nearly as interesting, but it would be better to offset the table toward the wall that 'can't be removed' and have that shift if the CB ended up on the nearby rail.

Regardless of my poopoo'ing. I want to see this beast in action. Let the build begin....