So What Does One Do When They Don't Have a Decent Local Mechanic...?

[tomatoshooter]

Looking forward to your final results! I want to do the same thing to my table. I was looking at the WPA specifications and they call for a 142 (+1) angle. Currently, I measure 5" opening and 4 3/16" at the throat. The distance between the measurements is 3", coming out to 142.86 degrees. Realistically, the corners are not quite sharp enough for me to claim that level of precision but let's take that at face value for now. These pockets are BRUTAL!!! Would that .86 degree make that big of a difference? Even going to 141 doesn't seem that big of a difference. Currently, a ball hit parallel to the end rail that hits the facing just inside the point will not go in. This isn't a hard hit ball, it would probably barely go the length of the table if hit in that direction. It's amazing what these pockets will spit out. If I align the balls against the nose of the cushion they will go but these pockets are remarkably stingy.

 

[The_JV]

10" sanding disk from a table saw with 50 grit sandpaper works beautifully for the compound miter in the pockets. And you bought the only saw that has virtually no deflection. 50grit means easy removal of wood and rubber at the same time with almost no pressure applied.

There is no better machine on this planet for doing the pocket miters than the right chop saw, used with a 10" sanding disk and 50grit sandpaper

Good to know that I made a strong choice in machine.

Didn't dawn on me to use a sanding disk made for the tablesaw in the miter. Certainly sounds like a much "safer" approach to producing the correct miter.

 

[The_JV]

If thats what in your mind for making the compound miter angles, good luck, have at it

I'm just riding the coat tails of those blazing the trail so to speak. I found these examples from a reputable source and figured they knew what they were doing, so why invent the wheel.

Now I'm not delusional enough to think I can mimic the above on my first go around. That's why I thought I'd just aim to get close and finish off via sanding. Now that you have pointed me in the direction of sanding the whole thing entirely. I think I'll lop off the cushion over hanging the rail extension and then sand down to the required angle.

Thanks for the pro advice.

 

[realkingcobra]

Looking forward to your final results! I want to do the same thing to my table. I was looking at the WPA specifications and they call for a 142 (+1) angle. Currently, I measure 5" opening and 4 3/16" at the throat. The distance between the measurements is 3", coming out to 142.86 degrees. Realistically, the corners are not quite sharp enough for me to claim that level of precision but let's take that at face value for now. These pockets are BRUTAL!!! Would that .86 degree make that big of a difference? Even going to 141 doesn't seem that big of a difference. Currently, a ball hit parallel to the end rail that hits the facing just inside the point will not go in. This isn't a hard hit ball, it would probably barely go the length of the table if hit in that direction. It's amazing what these pockets will spit out. If I align the balls against the nose of the cushion they will go but these pockets are remarkably stingy.

You and everyone else that likes to reference the "BCA" specs need to realize, the BCA DID NOT WRITE THOSE SPECS, they adopted them from a pool table manufacturer because before that happened, they had absolutely no idea what "Specs" even ment!!!

 

[The_JV]

A 141 miter on a pocket is a 51 degree reading on a chio saw, not 39.

Interesting... I smell an experiment coming on for this evening.

If a straight line equals 180 degrees, and I set a cut to 39. Then the remainder should be 141. Now that's purely mathematical, so I'm guessing there's something specific to cutting the miter with a chop saw.

Unless you're shooting for almost parallel pocket angles, and 105 miter angle for the side pockets is going to reject baaad!!

I mis-spoke... The goal is to be no more than 104 (WPA). I'm thinking that my use of the softer 60A facing material may require moving to 103.

For reference sake. Here are the diagramed numbers for WPA spec. Which is corners of 142 (38), and sides of 104 (76).

 

[The_JV]

You and everyone else that likes to reference the "BCA" specs need to realize, the BCA DID NOT WRITE THOSE SPECS, they adopted them from a pool table manufacturer because before that happened, they had absolutely no idea what "Specs" even ment!!!

Frankly, I couldn't care less what the BCA thinks my table should be. I want it to be somewhat unforgiving but fair.

I only cite the WPA numbers for sake of having a guideline others can freely reference.

 

[tomatoshooter]

I want it to be somewhat unforgiving but fair.

I like that, It wouldn't be right if they never rattled.

 

[realkingcobra]

Interesting... I smell an experiment coming on for this evening.

If a straight line equals 180 degrees, and I set a cut to 39. Then the remainder should be 141. Now that's purely mathematical, so I'm guessing there's something specific to cutting the miter with a chop saw.

I mis-spoke... The goal is to be no more than 104 (WPA). I'm thinking that my use of the softer 60A facing material may require moving to 103.

For reference sake. Here are the diagramed numbers for WPA spec. Which is corners of 142 (38), and sides of 104 (76).
View attachment 622001

Let me try and explain mathematics to you.

The straight down the side rails is 180 or 0 degrees, it's a straight line. Now take the 0 degrees as your straight line and make a 90 degree turn to the end rail, now you're at 90 degrees. Ok now, if you draw a line straight out from the apex of that 90 degree corner, the left and right side of that center line would be consider a 45 degree angle, so 90 + 45 = 135 degrees and in a corner pocket that means both pocket miter angles are parallel to each other, same opening in the front of the pocket as it is in the throat of the pocket. So now if you add another 6 degrees to that 135 miter angle you end up with 141 degrees. Well, you can't set a chop saw to a 141 miter angle so then take that 141 miter angle and subtract that 90 degree turn at the end rail, that gives you a matching angle to the end of the rail, cut off at 90 degrees, follow me so far?

So, 141 degrees minus 90 degrees leaves 51 degrees, and that you can set on a chop saw. Want to check my math, put a quality protractor along the nose of the cushion, 0 degrees, angle it to match one side of your corner pocket, that reading right there will tell you what the pocket miter is, be it 45, 46, 47, 48, 49, 50, 51, 52, or 53 degrees. Now take that damn rail and put it up against the fence if the chop saw, cushion first, and see if you can't then see the miter angle cut at the end of the rail lining up. DON'T CUT the damn rail and cushions with the saw blade, cut it a little wide with a bandsaw, jig saw, anything else. Now that you have the excess removed, set up you 10" sanding disk, set your miter and down angles, and SAND TO FINISH LINE! WASH, RINSE, AND REPEAT!!!

 

[tomatoshooter]

You and everyone else that likes to reference the "BCA" specs need to realize, the BCA DID NOT WRITE THOSE SPECS, they adopted them from a pool table manufacturer because before that happened, they had absolutely no idea what "Specs" even ment!!!

Fair enough but I assume that a standard exists and I would like my table to conform to that standard. I'd hate to uncork a 627 and people say my table isn't legit.

 

[realkingcobra]

I like that, It wouldn't be right if they never rattled.

The throat of the pockets must be smaller than the pocket mouth opening because the throat is controlled by the pocket opening, it can't be wider than the pocket casting have for an opening, so then to make the pocket mouth bigger, you open it up with the miter angles, it's about a 1/16th of an inch per degree per side so 6 degrees left and right open the mouth 3/4" wider than the throat, because it hasn't changed, only the mouth has gotten wider!!

 

[realkingcobra]

Fair enough but I assume that a standard exists and I would like my table to conform to that standard. I'd hate to uncork a 627 and people say my table isn't legit.

There's lots of reasons why your table pockets can reject balls, what table do you have??

 

[tomatoshooter]

Let me try and explain mathematics to you.

The straight down the side rails is 180 or 0 degrees, it's a straight line. Now take the 0 degrees as your straight line and make a 90 degree turn to the end rail, now you're at 90 degrees. Ok now, if you draw a line straight out from the apex of that 90 degree corner, the left and right side of that center line would be consider a 45 degree angle, so 90 + 45 = 135 degrees and in a corner pocket that means both pocket miter angles are parallel to each other, same opening in the front of the pocket as it is in the throat of the pocket. So now if you add another 6 degrees to that 135 miter angle you end up with 141 degrees. Well, you can't set a chop saw to a 141 miter angle so then take that 141 miter angle and subtract that 90 degree turn at the end rail, that gives you a matching angle to the end of the rail, cut off at 90 degrees, follow me so far?

So, 141 degrees minus 90 degrees leaves 51 degrees, and that you can set on a chop saw. Want to check my math, put a quality protractor along the nose of the cushion, 0 degrees, angle it to match one side of your corner pocket, that reading right there will tell you what the pocket miter is, be it 45, 46, 47, 48, 49, 50, 51, 52, or 53 degrees. Now take that damn rail and put it up against the fence if the chop saw, cushion first, and see if you can't then see the miter angle cut at the end of the rail lining up. DON'T CUT the damn rail and cushions with the saw blade, cut it a little wide with a bandsaw, jig saw, anything else. Now that you have the excess removed, set up you 10" sanding disk, set your miter and down angles, and SAND TO FINISH LINE! WASH, RINSE, AND REPEAT!!!

Yeah the 141 is, well, anybody that cuts stuff starts out thinking perpendicular is zero and goes from there. It seems strange that the back cut angle is given in terms of difference to vertical, like most people would think, and the face angle is compared to the nose.

 

[realkingcobra]

Yeah the 141 is, well, anybody that cuts stuff starts out thinking perpendicular is zero and goes from there. It seems strange that the back cut angle is given in terms of difference to vertical, like most people would think, and the face angle is compared to the nose.

When drawing blue prints, you must indicate the full 141 miter angle in order to write it on paper, which is how drafting works. But you need to know how to translate that to the equipment you're working with

 

[tomatoshooter]

There's lots of reasons why your table pockets can reject balls, what table do you have??

Olhausen. I've heard that the pocket facings on Olhausens are soft but I don't know what 60 durometer should feel like. It feels like someone could have used credit card material for the facings, poking at it with my finger does not reveal anything to me.

 

[realkingcobra]

Olhausen. I've heard that the pocket facings on Olhausens are soft but I don't know what 60 durometer should feel like. It feels like someone could have used credit card material for the facings, poking at it with my finger does not reveal anything to me.

Olhausen equals soft cushions, soft facings. Ball hits the outer half of the facing, facing and cushion compress/bend away from the impact of the ball, changing the angle of the ball coming off the cushion to across the pocket instead if deflecting it towards the throat of the pocket.

3/16" 60A neoprene facings stop the compression, therefore deflecting the balls into the throat of the pocket, no more Olhausen rattle!!!

 

[The_JV]

Let me try and explain mathematics to you.

lol... Man you're awesome.

The straight down the side rails is 180 or 0 degrees, it's a straight line. Now take the 0 degrees as your straight line and make a 90 degree turn to the end rail, now you're at 90 degrees. Ok now, if you draw a line straight out from the apex of that 90 degree corner, the left and right side of that center line would be consider a 45 degree angle, so 90 + 45 = 135 degrees and in a corner pocket that means both pocket miter angles are parallel to each other, same opening in the front of the pocket as it is in the throat of the pocket. So now if you add another 6 degrees to that 135 miter angle you end up with 141 degrees. Well, you can't set a chop saw to a 141 miter angle so then take that 141 miter angle and subtract that 90 degree turn at the end rail, that gives you a matching angle to the end of the rail, cut off at 90 degrees, follow me so far?

So, 141 degrees minus 90 degrees leaves 51 degrees, and that you can set on a chop saw.

Ah, you see I was just thinking in terms of math. You are explaining within situational circumstances of setting up the saw. 39 degrees retarded from 180, is the same as 51 degrees advanced from 90. Both amount to 141. Really boils down to which way you swing your saw . If you want to check my math, just add 39 and 51.

Kidding aside. The mitersaw as you of course know, considers a 90 degree setting as 0. Swinging to 51 degrees in either direction is how is physically needs to be done to perform the cut. Excellent insight for those who don't live in my mind.

Want to check my math...

Nope, don't need to. Your math isn't in question. Your prespective was just different than mine is all.

DON'T CUT the damn rail and cushions with the saw blade, cut it a little wide with a bandsaw, jig saw, anything else. Now that you have the excess removed, set up you 10" sanding disk, set your miter and down angles, and SAND TO FINISH LINE! WASH, RINSE, AND REPEAT!!!

Understood, and I have already sourced a 10" sanding disk to handle the task of cleaning up to my miters. Fortunately there's isn't a ton of material to be removed from my subrail extensions, so I could probably stretch out the process a little bit and use the sander the whole way.

Thanks for taking the time to hold my hand Glen. Very appreciated.

 

[dendweller]

Corner Pockets:

• 4.5" (114.3mm)
• Facing material thickness: 0.200" (5.08mm)
• Facing material thickness at 39 degrees: 0.3178" (8.07mm)

Given the facing thickness of 0.200" how do you calculate the actual reduction in pocket size at the angle you cut the pocket? In other words, thickness measured at an angle.

 

[The_JV]

Given the facing thickness of 0.200" how do you calculate the actual reduction in pocket size at the angle you cut the pocket? In other words, thickness measured at an angle.

I'm happy and extremely fortunate that you asked.

I used an online 'right angle triangle' calculator. That link inlcudes the new math Glen taught me. I had actually made a mistake by using 39 (which is actually the outside angle) instead of 51, (inside). That greatly changes the resulting hypotenuse (answer 'c'), which is the value that directly effects the pocket opening.

Normally I perfer to leave my mistakes documented within 'build threads', but this one may end up really confusing someone and I don't want to be responsible for having someone mis-cut their rails. I'll double back and make the corrections within that post with a note so the broken conversation isn't too confusing to new readers.

I also added a link to this online calculator.

 

[The_JV]

Given the facing thickness of 0.200" how do you calculate the actual reduction in pocket size at the angle you cut the pocket? In other words, thickness measured at an angle.

I'm deep into procastination mode this morning so I had a go at sketching out the facing math in paint. Apologies in advance for the rough pic.

So the white void represents the part of the facing that allows me to use the triangle calculator. Lurkers please note that the intent isn't to stop the facing short of the rail. Again, that area is left white just as means to illustrate the portion of facing used in the calculator. The nominal thickness of the facing material and an angle is all that's needed. The 90 degrees is a constant.

 

[fastone371]

I'm deep into procastination mode this morning so I had a go at sketching out the facing math in paint. Apologies in advance for the rough pic.
View attachment 622083
So the white void represents the part of the facing that allows me to use the triangle calculator. Lurkers please note that the intent isn't to stop the facing short of the rail. Again, that area is left white just as means to illustrate the portion of facing used in the calculator. The nominal thickness of the facing material and an angle is all that's needed. The 90 degrees is a constant.

I have to do a lot of figuring like this for my work. Because I already knew everything there was to know when I was 15 year old idiot I never took advanced algebra, geometry, trig, and other useful math classes like that in school. Now I pay the price for it everyday. I make drawings like that everyday so I don't screw up because it takes so long to fix mistakes when working with metal. When people ask how I got so good at what I do I tell them "by getting a lot of experience running a Sawzall and a grinder", they think I kid them, unfortunately I do not.