big trackball

[jakejake28]

does any one know where to find one of those monstrous bowling ball trackballs used in that old midway bowling game (it is cocktail, there is one down the street, guy won't seell it), or even something smaller, but no smaller than 6 inches? if i find one, is there a way for me to hook this to my pc?

[paigeoliver]

Look for an Atari Football trackball. I don't recall the size, but they are pretty mighty. Opti-pac should interface most any trackball.

[MinerAl]

Generic Eric and I have had a few threads abut this lately.

"Giant Balls!"

"My Giant trackball"

If you do searches for "Atari Football" and "4.5 track" you might come up with more.

Short version:  The stock Atari 4.5" trackballs are compatible with Opti-PAC and probably even mouse hacks and the like.  Happs sells a 4.5" trackball for a lot of money.  Ebay occasionally has them, and they go for a tidy sum there as well.  GE is making his own.  I've interfaced mine to an Opti-PAC with OSCAR's help, and it is talking USB to my MAME machine.  They have an awesome but heavy feel to them, as the balls weigh about 2.5 pounds (1kg).  You can replace the stock black balls with colorful 4.5 inch candlepin bowling balls.  The original Atari mechanisms are designed for mounting under metal control panels, so mounting them under wood may be unsatisfactory.  Don't know what the modern Happs 4.5"ers are designed to mount in (anyone?).

I like my giant balls, and invite my friends to play with them frequently. (couldn't resist)

[Generic Eric]

From a private message:

The atari 4.5" tball did not use anything on the rollers to protect the ball, nor did any trackball that I've ever seen.  This trackball used fairly large rollers and bearings (3/8" diameter, I think).

If I were to build one, I would start with www.mcmaster.com.  Their part number 98381A634 is a 3/8" hardened dowel pin 2.5" long (maybe it's long enough, I haven't gone through the math?).  Then look for ball bearings designed for 3/8" shafts, also available from mcmaster.  The steel, or aluminum, frame could be built from flat or angle stock available from Home Depot or mcmaster.

As for the project, I haven't really come up with much yet.  Go hereFor the exploded mounting view of the trackball.

[jakejake28]

alright, i hope that now i can start my quest for giant balls .  thannks guys.