What type of rubber is on my table?

[MrWrestlingII]

I recently purchased an old Brunswick Anniversary table and am trying to figure out of it has k66 or k55 rubber currently installed. The rubber is in good shape so I would rather not replace it but also want the table to play right.

Since the rubber is still installed the measurement I?ve made is from the cushion/sub-rail seam to the cushion edge (where the ball makes contact with the cushion). This measures 1 1/8?. Since the cushion facing?s are still installed I can?t make an accurate measurement on the backside where the rubber is glued to the sub-rail.

With the rail flat on my work bench I measure 1 ?? from the bench to the cushion edge.

The rubber is flush with the top of the sub-rail and the sub-rail is about 1/8? below the rail height. With the cloth installed the cloth is flush to the rail.

I have no experience on this subject but from the research I?ve done on this site I believe this is k66.

Any thoughts?

 

[realkingcobra]

Is this the table you bought from Colorado? The rails were designed for K55 cushions, and some hack modified them to take K66 cushions. I'm driving right now, so I'll explain later.

Glen

 

[realkingcobra]

Okay, I'm back home and off the road. Now, about your rails. If you'll look at the bevel of the sub-rail, where the cushion is flush to the top of the rail, I think you'll notice that looking at it from the long way...down the rail, you'll notice that it kind of slants downward toward the rubber. This is caused by belt sanding the sub-rail down about an 1/8" of an inch in order to mount the K66 cushions. As I've described in some of my earlier posts, K66 mounted normally on K55 rails, sits at about 1 9/16" of an inch high at the point of the cushion where the ball makes contact. Lowering down the cushion by it's self would leave an 1/8" lip at the top of the cushion creating a ledge so to speak, a drop off from the sub-rail to the top of the cushion, BUT...NOOOOO, someone got the bright idea to belt sand the rails to make them LOOK like they fit. Now, when someone does that, what they end up doing is YES, they have the point of the cushion at the right playing height, BUT...the cushion rubber is at an upward angle so to speak, instead of behind it's own point of cushion/ball point of contact. What this does, is causes the point of cushion, on impact from an object ball, to lift upward, and kind of pinch the ball, instead of rebounding back into the bulk of it's own body of rubber, which is what needs to happen in order to bank the balls correctly.

Here's a test you can do to check out the difference in the banks from a table that has the cushions mounted wrong vs cushions mounted right.

Place a cube of chalk on the cushion, laid flush with the edge of the sub-rail where the cushion mounts to the rail. Bank a ball into the cushion and watch the reaction of the cube of chalk. Yes, it'll jump off the rail, but compare how it jumps off the bad mounted cushions vs the correctly mounted cushions.

On the cushions mounted correctly, it won't jump nearly as high as it does when compared to the cushions mounted incorrectly.

Glen

 

[MrWrestlingII]

Glen,

Thanks for detailed response. I really can't tell if the top of the subrail is slanted toward the rubber but it would be safe to assume that it has been sanded down if it's got k66 rubber on it.
The question now is what are my options? If the bevel angle of the subrail has not been modified can I have k55 installed and then tack in a shim on top of the subrail to make up the 1/8"? I can't think of any other options.

Todd

 

[realkingcobra]

Glen,

Thanks for detailed response. I really can't tell if the top of the subrail is slanted toward the rubber but it would be safe to assume that it has been sanded down if it's got k66 rubber on it.
The question now is what are my options? If the bevel angle of the subrail has not been modified can I have k55 installed and then tack in a shim on top of the subrail to make up the 1/8"? I can't think of any other options.

Todd

Todd, check at the bottom edge of the cushion rubber, underneath. Is the edge of the rubber flush with the sub-rail? If you're going to correct the sanding of the sub-rail, you're going to have to dado off the top of the sub-rail that was sanded down, then replace it. If you place a square on top of the rail, you'll be able to see the results of the sanding. I don't know how to tell you all the steps needed to "fix up" your rails, because I don't know what tools you have, or what kind of wood working background you have, or for that matter, your understanding of what I'm trying to explain. I'm not trying to make this look bad, but I don't know what your capable of doing, on your end, to fix your table.

Glen

 

[Dartman]

OP
If the subrail is 1/8 below top of rail how is the cloth flush with top of rail (and across the top of the cushion)?

The back of the cushion should match the subrail face perfectly. If they put K66 on a subrail designed for K55 - part of the subrail face below the cushion will be visable (as RKC mentioned). It's possible no sanding was done and they just used the wrong cushion profile.

Maybe a few close-up photos will help to further diagnose what's going on.

 

[MrWrestlingII]

Glen,
I'll pull off one of the cushion facings and check to see if the rubber is flush with the bottom of the subrail.
As to skill set, I do have a good table saw, miter saw and other tools. My woodworking skill set is reasonable and I also have friends with good woodworking abilities. I should be able to understand anything you try to explain although I may need to study it for a bit and ask a few questions.

Rick,
I'll get some pictures posted shortly.

Thank you for the help. If not for this forum I never would have even suspected there was a problem.

 

[Dartman]

Just pull the cloth and look at the bottom of the cushion. No need to pull a facing off but if you do - measure the back part of the cushion. 1 1/8" will confirm the cushion is K66.

 

[realkingcobra]

OP
If the subrail is 1/8 below top of rail how is the cloth flush with top of rail (and across the top of the cushion)?

The back of the cushion should match the subrail face perfectly. If they put K66 on a subrail designed for K55 - part of the subrail face below the cushion will be visable (as RKC mentioned). It's possible no sanding was done and they just used the wrong cushion profile.

Maybe a few close-up photos will help to further diagnose what's going on.

Rick, what the hack did was lower the K66 rubber down on the face of the sub-rail to maintain the 1 7/16" cushion height, then to remove the ledge left over at the top of the rail, sanded it down at an angle to flush it up with the cushion rubber at the top edge. The cloth would still be flush with the feather strip at the finnish of the rail. I've seen this many times in the past, some of it done be a certain technician that most know of.

Glen

 

[Dartman]

Aha. Got it.

 

[MrWrestlingII]

Guys,
I should have removed a cushion facing earlier. From the measurement on the backside of the cushion it looks like this is k55. I took a straight edge and ran it parallel to the bottom edge of the cushion then measured from that edge to the top of the cushion, it measured 1 1/4 inches. I can't get a picture of that because it takes both of my hands to make the measurement.
Please forgive my ignorance, I don't want to waste anybody's time here.
I'll post some pictures here in a second...
How do you determine if the rubber needs to be replaced? It is still soft and there are no cracks although in some places it is a shade darker then others.

 

[Dartman]

Typical dimension of back of cushion that is glued to subrail -

If you measured 1 1/4" then the cushions you have should be K55

 

[MrWrestlingII]

Here are some pictures

 

[Dartman]

IMO - I do not see where the subrail was sanded. Looks to me like the top of the cushion is mounted correctly. I see about 1/8 or so under the bottom of the cushion suggesting they used K66 when K55 should have been used. On picture# 2 it looks like a cut or something on the rubber or a slice of the subrail is missing. My eyes aren't the greatest so let's see what RKC and the other mechs think.

BTW - is each rail the same?

 

[MrWrestlingII]

Yeah, It's just under 1 1/14 inches on the backside of the cushion. My problem was that I didn't remove a cushion facing and measure that first. I was hesitant to do that because I don't want to replace what I don't need to.
The measurement from the top subrail/cushion seam to the tip of the cushion is closer to 1 1/8 inch but that measurement is more difficult to make because of the arc in the cushion.

 

[MrWrestlingII]

Rick,

You are correct, there is about a 1/8 of an inch at the bottom of the subrail.

 

[Dartman]

The height of the glue surface of the cushion should match the height of the subrail with no under/overhang. I just can't tell if any sanding was done from the pics. Maybe someone else can. I think it would be safe to say that if No sanding was done on the subrail then you just have the wrong profile cushions. Give the other mechs a chance to weigh in and see what they think.

 

[realkingcobra]

The pictures are to close up, but that rubber don't look like Brunswick Super Speed to me, wrong color for one thing. And it don't look like the top rails are sanded either. Measure the height of the nose of the cushion again, make sure the rail is flat on the surface first. THAT cushion rubber still looks like it's K66. Take some pictures further away, so I can see the whole rail. From point of cushion to the sub-rail, Brunswick Super Speed is 1 3/16", K55 is 1 1/4", and K66 is 1 1/8". K55 will work to replace the Brunswick rubber, but K66 will not, unless extensive sub-rail work is performed first, and I can tell by the pictures you posted, that work has NOT been done. What's throwing me off, is that you stated that the point of the cushion was at 1 7/16", and that can only happen with K66 rubber if the cushions are mounted low first, by an 1/8" of an inch, or the bevel of the sub-rail is re-cut from 21 degree's down to 18 degrees. In which case, had that been done, you'd have a lot more sub-rail sticking out past the bottom of the cushion, unless the sub-rail was undercut to bring up the bottom of the rail to match the cushion rubber...which I can see was not done.


More pictures please.

Glen

 

[Donny Wessels]

The cushion looks like k55 to me. I dont understand what the problem is, is the ball jumping off the table?

 

[MrWrestlingII]

Glen, Here are some more pics.