trackball question

[wfg97079]

I have a control panel with a  2.5 inch hole in it, does this mean I would need a 2.5 inch trackball?  just not clear on what is measured to determine trackball size

[rampy]

not necessarily... the size of the trackball refers to the overal diameter of the ball.  Even a 3" trackball (depending on flavor/type highball, vs highlip, vs standard) doesn't expose ALL 3 inches above the CP.

What was the control panel from originally (that would help some)?

It's *probably* a 3" trackball as the other "normal" sized tracball diameter is 2 and 1/4" (for the ball itself, not the hole, mind you)

Hope that helps...

rampy

[wfg97079]

very helpful
the panel is from a pacman that was converted to centipede
so a 3" could work?

[u_rebelscum]

Generally, a 3" trackball uses a 3" hole, and a 2 1/4" ball uses a 2 1/4" hole, but that's not why they are called that.  (rampy right in that the ball diameter is whatever size the TB is called.)

All arcade trackballs have a "lip" or "rim" around where the ball sticks out of the case.  The lip is usually ~1/4" wide.  So, if you don't mind the ball being lower than normal (ie: the lip under the CP instead of level with the top of the CP), you could use a 3" ball in your 2.5" hole.  If you use a 2 1/4" TB, you'll have a 1/4" gap between the lip and the CP.

Look at happs mounted view to see the outside of the lip diameter to be 2.99", and the exposed ball to be smaller than that.

[rampy]

Generally, a 3" trackball uses a 3" hole, and a 2 1/4" ball uses a 2 1/4" hole, but that's not why they are called that.  (rampy right in that the ball diameter is whatever size the TB is called.)

All arcade trackballs have a "lip" or "rim" around where the ball sticks out of the case.  The lip is usually ~1/4" wide.  So, if you don't mind the ball being lower than normal (ie: the lip under the CP instead of level with the top of the CP), you could use a 3" ball in your 2.5" hole.  If you use a 2 1/4" TB, you'll have a 1/4" gap between the lip and the CP.

Look at happs mounted view to see the outside of the lip diameter to be 2.99", and the exposed ball to be smaller than that.

Oy, I did dork up my assumptions though...  I hope I didn't steer wfg too far off the track...  listen to u_rebel (he knows what he is talking about and check the happs mounting diagrams he linked to...

disregard the man behind the curtain...

sorry about that wfg...

rampy

[wfg97079]

OK
I have some pics of the panel
posted at http://www.miltonsoffice.com
Let me know what you think aould be the best trackball size for me
Thanks again guys!

[Thenasty]

I think that 3" is no good with that hole. Even tho it will fit, it will be low and your hand will be hitting the part of the Hole-CP. You need a ball that will show/lift up higher than the hole, so I think the 2"1/4 should be perfect, unless you wanna make the hole bigger and shove in a 3".

[paigeoliver]

Looks like a hole for a 2.25 trackball to me. Which is also the size used by Centipede.