Quoted from vintage4life:
I cannot get my left vuk to fire the ball up to the ramp consistently. It will sometimes go half way up and fall back into the vuk. Doesn’t happen all the time. It’s random. I have messed with the coil power. Makes no difference. Anyone dealt with this?
I had the same behavior.
The ball was actually bouncing off the inside roof of the wireform and falling back down.
This is due to tight first bend in it. A straight shot to the top, rattles and falls back down.
It needs more of a gentle bend to work right. Its a design flaw, but it works somewhat.
I changed the bend 1/8" and had a good but nominal result.
I had a better result from adding a 1/16" washer under the front of the mech to shoot the ball at a slight angle, along the outer edge and "roll" over the top, into the horizontal area of the wireform.
Carefully adjusting the power upwards and downwards can get the VUK to be more consistant.
You milage make vary on this, to the point of adding washers to the rear of the mech to help bounce the ball onto the horizontal span.
I have tried it both ways with acceptable results.
Another behavior is that the ball will make it all the way to the second bend in the wireform, bounce off the front wall and roll all the way back down to the mech.
Opening up the second bend slightly can help with this.
I stuffed the ends of the wireform with properly fitting PVC pipe lengths to GENTLY make SMALL bends.
Being too aggressive can fail the welded joints.