Can I use a Happ 3" trackball plate with an Imperial 3" ball?

[AlanS17]

I would like to flush-mount my trackball, but I need a Happ plate to do it. Can I fit an Imperial 3" trackball onto a Happ 3" plate?

[rampy]

I would like to flush-mount my trackball, but I need a Happ plate to do it. Can I fit an Imperial 3" trackball onto a Happ 3" plate?

yes you can... I did it with the non-flush plate... but the mounting holes are near-standard...

Rampy

[u_rebelscum]

I would like to flush-mount my trackball, but I need a Happ plate to do it. Can I fit an Imperial 3" trackball onto a Happ 3" plate?

Yes, I used the flush-mount plate.  3" Trackball holes are standardized (size & location).

BTW, my Betson/Imperial TB leaves a little itty-bity bigger space around the TB lip than my happs TB; approx 1/16" diameter difference, so 1/32" space all the way around if mounted perfectly centered.

[AlanS17]

I kind of figured this was the case. That's why I asked. There's one more part I can order from Bob Roberts! I need to compile a list...

[mccall]

I had to enlarge the holes on my Imperial to use the Happs boltless plate. Not much, just slightly. I'm not sure if I had an older model and that was the reason or if the newer ones also need this.

[AlanS17]

I had to enlarge the holes on my Imperial to use the Happs boltless plate. Not much, just slightly. I'm not sure if I had an older model and that was the reason or if the newer ones also need this.

Doesn't sound like a problem that a good mallet can't fix.  

[mccall]

Yeah, some friendly persuasion from a large mallot would probably have worked ;-)

It wasn't much, just a shaving actually, and it was only on the top inch or so of the top of the housing. It took all of 30 seconds to do with a snug fitting drill bit. I read where you can "shave off" the black paint around the inner mounting bolts of the Happs plate and that will also work, but I read it after I shaved my TB with a drill bit so I do know personally whether it works or not.

[u_rebelscum]

I had to enlarge the holes on my Imperial to use the Happs boltless plate. Not much, just slightly. I'm not sure if I had an older model and that was the reason or if the newer ones also need this.

Hmm, I had to do that with my wico TB, but not my betson TB.  FWIW, the betson I have is a "golden tee" "high lip" TB.

[mccall]

Mine was not the high lip version, maybe there's the difference.