Gold Pinball Durability Test

Copyright (c) 2007 By TheKorn

Last Update: March 1st, 2007


Terry over at Pinball Life has a supplier with a new formulation of gold balls. Being the fastidious retailer that he is, he wanted someone relatively independent to test this new formulation, and specifically how this ball would behave over time. This page is an attempt to document that testing.

Terry writes:

The balls you tested are 14k gold pinballs with .0035 mirco-inches of gold on them. The gold was "micoware fused" on, whatever that means. The original gold balls that came out about 6 months ago (and are the balls that pretty much everybody that bought gold balls has) was 24k gold with .0020 mirco-inches of gold. 14k gold is less pure, therefore harder and more durable, or so the theory goes.

Testing methodology: Eight balls from the same new run were used. One ball was separated out and used as a control. The control was placed into a plastic bag and never placed into play on any game at any time. The remaining balls were used in two games, Rollergames and Tee'd Off. Balls were pulled and photographed after ten games, twenty-five games, and fifty games.

Unless otherwise noted, photos related to Rollergames will be on the left, and Tee'd Off will be on the right.

Click on ANY picture to see a very high resolution version of the same shot.



The Test Games

In the red corner, weighing in at 200 pounds, we have... ROLLERGAMES! In the blue corner, weighing in at a muscular 215 pounds, we have Tee'd Off!

I chose these two games for similar reasons; they both have lots of metal to metal contact. In the case of Rollergames, the game has lots of metal wireforms, and also has that lock trick where it cycles the balls around. In the case of Tee'd Off, the game has a HUGE wireform that leads from the upper-left corner of the game to the lower-right, along with a secondary wireform that starts in the middle-rear of the playfield and leads to the left flipper. Plenty of opportunity for metal to metal rubbing on both of these games.

Three balls were placed into Rollergames, and four balls were placed into Tee'd Off.




Weighing the balls

First thing was to weigh the balls. For this test, I would turn the scale on, zero it, place balls on scale, take a reading, remove balls, then turn the scale off. I repeated each measurement four times, then averaged them.

SURPRISE! The gold balls averaged out to be half a gram heavier than their NOS silver counterparts. Whether this bothers you or not is up to personal taste; on a game that I wasn't familiar with I probably would not have noticed. But I was testing on my games in my house, and I could feel that there was something slightly different almost immediately.

Silver balls average weight: 323g / 4 balls.

Gold balls average weight: 325g / 4 balls.




Before entry, everybody all pretty (Rollergames only)

These are shots of the control ball (not played in either game) and the balls that went into Rollergames. You'll have to excuse the cleaning fluid on the shop towel.




After 10 games: A tale of two cities? (1 of 2)

Almost immediately, the balls showed very different wear patterns in the two games. The balls in Rollergames already are showing signs of damage; mainly just surface scratches at this point. By comparison, the balls in Tee'd Off still look pretty good.




After 10 games: A tale of two cities? (2 of 2)

Here is a shot with the same balls, plus the control for reference.




After 10 games: Where's the beef?

As part of the test, I wanted to see if the gold balls were flaking their golden goodness onto the playfield. Both games were cleaned before play started, and the flipper rubbers photographed at each interval. Unfortunately I neglected to get a shot of Tee'd Off's flippers at the ten game interval, so only the Rollergames shot is available at the ten game interval.

Not too dirty, yet slightly more grunge than I was expecting.




After 25 games: Soothe my damaged heart!

Here the damage on the Rollergames side was starting to become more apparent. Tee'd Off still looks a lot better, but is also starting to show some light scratching.




After 25 games: Wasn't grunge a fad in the 90's... ?

Left flipper on both games. More grunge on the Rollergames flipper than the Tee'd Off flipper.



After 25 games: ...and wasn't Kurt Cobain still alive?

Pretty much the same story with the right flippers; definitely more of the black stuff building up on Rollergames than Tee'd Off.



After 50 games: Rollergames wasn't doing so well.

After 50 games, I took the exact same shot of the balls in Rollergames both with and without a flash. As can be seen, there is a significant amount of surface scratches that can be seen, and the balls are pretty far off their peak luster and shine.

Though the gold coating was still on the balls, I began to wonder how long that would be the case for Rollergames.




After 50 games: Rollergames again.

Here is one of Rollergames' balls after 50 games, next to the control with and without flash. What a difference!



After 50 games: Tee'd Off

Tee'd Off's balls, by comparison, still looked pretty good. Not immaculate, but I wouldn't expect that.



After 50 games: Tee'd Off again.

And a random ball from Tee'd Off with the control, both with and without flash.



The weigh-out...

SURPRISE! The balls weighed less after 50 plays! What's even more surprising (...or maybe not...) is that the Rollergames balls weighed less than their brothers in Tee'd Off. (For Rollergames, I added the control ball so that I had four balls to weigh for each game.)

Rollergames average weight: 323.5g / 4 balls. (80.875 g/ball)

Tee'd Off average weight: 324g / 4 balls. (81 g/ball)

Pre-play average weight: 325g / 4 balls. (81.25 g/ball)

But if you subtract out the weight of the control ball from Rollergames' set, the remaining balls had an average weight of 80.75 g/ball, for a net average loss of 0.5 g/ball over 50 games.

(All measurements taken four times and averaged using the same method as the initial weigh-in.)




So that's where it all went!

After looking at the flipper rubbers, I think it's pretty obvious where the missing weight went!




So that's where it all went! (Part two)

And the other side, just for good measure.




The culprit

I believe the critical difference between the two games is the magnet on Rollergames. I believe this exposed magnet pole acts like a piece of metal sandpaper. That the flipper then has to sweep the ball off the magnet then compounds the problem. Hard on the balls and playfield alike!




The bottom line

These new balls aren't perfect. The balls in Tee'd Off seemed to hold up fairly well, and the balls in Rollergames fared far worse. As a result, I would guess that any game that has an exposed magnet pole (Theatre of Magic, World Cup Soccer '94) would be a bad choice for these balls. There is some speculation that games with spinning discs (Whirlwind, Pirates of the Caribbean) are also hard on balls, but that was not tested here.

Outside of those types of games, the gold balls seem to hold up OK. Still not as durable as a pure carbon steel ball, but that doesn't come as any surprise really, because gold is a much more soft material than steel.

The bottom line is that I wouldn't use these balls for everyday play; they're just not durable enough for continual use. But if you want to "glam up" a machine for a party, you should be fine.





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