My game had a bad mini playfield board. The "G" led wasn't lighting at all and I was getting a ghosting light effect on other nearby leds when the lights should be off. The game had been this way since new but never noticed until I looked closely at it.
Insert G should be on and it is not
I and N inserts ghosting when lights should be off
I emailed Barry and he sold me a new mini playfield board for €70,00. DP sells the MPF upgrade kit (€250 I think?) that includes a new PCB, but I decided to forgo that upgrade.
The original TBL mini playfield pcb
The new TBL mini playfield pcb
If you get the upgrade kit the new PCB has room to move the stepper motor up to under the MPF. I looked through the upgrade instructions and decided moving the stepper wasn't for me. Though I did end up doing just as much work on my own solution as the MPF upgrade. Probably worth just upgrading if you're doing this.
While I was under the MPF, I made a few extra changes:
The early MPF plastic ramp didn't have a hole for your screw driver to remove this bolt. Later builds have a hole from my understanding. I was able to get the screw off/on without it, but when I had to take this off again, I got fed up and made the hole.
The early ball guide - no hole
Made my own hole
I never loved the white rubber and red targets on the MPF. Always felt like the handicap targets should be blue. I know there are stickers, maybe I'll order those, but while I'm here I switched out the targets. Also switched the post sleeve rubber to grey to match the building better. Using standard gray post sleeve from Titan.
Gray post sleeve rubber on the MPF
The rubber needed a little heat to remove from the posts
Blue targets are a DIY project. The red ones appear to be a standard Williams part (minus the connector). Pinball Life sells the targets in red (pbl-100-0060-00) but I couldn't find blue assembled anywhere. Marco sells the blue caps (#03-8304-1) and PBL had the rivets you need. Semi Tubular Rivets 5/32", 9/16", and Rivet Washers. Though I forgot to put the washer on this one but it didn't seem to make any difference. I followed THIS guide.
Making a blue standup targets for TBL
Blue standup targets for TBL
The last upgrade I wanted to do was replacing the plumbing fitting that connects the garage door to the stepper motor. The MPF upgrade kit fixes this, but moves the stepper up top. As others have discussed before, I bought a coupling with threaded pins to replace the brass plumbing one.
replacement coupling
I bought this coupling off (https://www.amazon.com/gp/product/B07P95G6ZK) Amazon but warning it does need to modified. The shaft and stepper rod are both 5mm. The coupling I found was only 5mm on one side and 4mm on the other. I drilled out the part with a 5mm bit to make it work. You won't just find a 5mm bit at harbor freight. Plan to order this if you're doing this yourself as I had to order a set from Amazon after learning this.
Drilling a 5mm hole
finished TBL stepper motor coupling
Stepper motor with new coupling
When reassembling the MPF, I fixed an alignment issue I've always had on the Walter ramp. It was just too low on mine and the lip seemed to cause a lot of balls to fall backward. I added washers under the ramp to make it flush with the MPF.
Washers under the Walter ramp to make it flush
And that's it I put the MPF back together and now have working lights with blue targets and gray rubber. Though I still need to order the right size translucent ring.
Blue handicap targets and grey post sleeves