Darn! If this would only happen when I'm in Vegas, so I could know which number to bet on.

Take apart and clean the whole spinner mech good. Clean and wax the whole top of the spinner wheel & add a fresh new ball, also waxed. That should give you more random results.

I wonder if the playfield pitch affects where the ball lands. If the pitch was steep enough you could probably get it to land in the same spot most of the time. Have you tried it at different playfield angles?

For those who haven't see one up close there's video of one from above and below at:
https://www.funwithpinball.com/exhibits/small-boards-page-2#SpinnerUnit

/Mark

I used to have a Williams Suspense with a similar roulette wheel and the ball usually landed in the same spot (or close) but the wheel itself usually stopped at different positions so even though the ball landed in the same physical spot I still got random scoring. Does your wheel always land in the same spot?

I fixed up and owned a Fan-Tas-Tic many years ago, I don't recall it landing in the same spot, that would have bugged me. Is there any way you can adjust the angle of the roulette unit itself using spacers or washers under two of its mounting points + longer screws if needed, so that it is closer to level? Changing the slant of the playfield probably doesn't make much diff as you saw in your testing, one or two degrees, plus not the best way to fix this issue unless the slant is all whacked out to begin with.

When I first read this I was puzzled but now that i think about it, it makes sense. Playfield angle does play a part. Think of a Hot Wheels car on a loop track. When the car made it over the top of the loop they stayed on the track, but if they lost momentum they would drop like a rock when they got to the top of the loop.

So the ball spins along the outside edge. It loses momentum as it goes uphill to 12 o'clock. If it has enough momentum to get past 12 o'clock it picks up a little speed as it comes back down. Eventually the momentum is reduced until gravity takes over and the ball falls down into the hole. This spot will usually be right at the apex or 12 o'clock position.

It would be real hard for it to land in the bottom holes (especially 6 o'clock) because the ball will gain speed as it comes off the loop. The ball would need to have almost no momentum at all, because at the 6 o''clock position the ball would have to (for lack of a better word) fall up, as the holes on the bottom edge will be above the balls path.

This wouldn't be a factor if the roulette wheel were level, like in Vegas. This might be one of the cases were shiny and smooth are not what you want. If you had more friction from either the ball or the edge of the wheel you would probably get more random results.

I had a Fan Tas Tic and I didn't experience the ball always ending in the same (12 O'clock) position. Do you have a picture of the roulette wheel and the ball that you are currently using?

If the wheel does seem like it's slanted towards the player now as described above where the ball slows down at the top, how about just sticking different books under the front legs as a test to then measure how many degrees the wheel unit would need to be 'adjusted' for it to be close to level.