Nishijin Lucky Welcome Arrangeball Repairs
First things first: When working on Japanese domestics products, use JIS screwdrivers to avoid stripping the screws. Here's the set I use on my games.
I guess a good starting point for the repairs is the auction item description:
Translation from YJA
First issue: "there were places where the ball did not light up"
That was a funny one. The first time I played the game, I noticed the wrong number would light up on the card. Example: I'd hit a 11 and 6 would light up or hit 2 and 14 would light up.
At first I thought the connector for the card light PCB might have been plugged backwards, the wiring loom did have an unnatural kink going to the board, but I noticed the connector was keyed when I pulled it, so that wasn't the problem. Turns out it was just the whole card lamp board was installed upside down. As can be seen in the auction picture below.
Picture from YJA
Light board right side up
Second issue: "Pachinko balls can be hit endlessly."
That one was a lever to the ball release coil that was intentionally pulled by repositioning the return spring, jamming the ball release gate in the open position, so that the balls would continuously circulate to the shooter. Flipped the lever back in it's intended position and bingo.
Ball release fixed
The MAJOR problem with this game was the card that was melted into an unsightly mess. It didn't affect gameplay but it looked awful.
I decided to try flattening the card using my kitchen oven. But first I had to remove the card.
To remove the card, first I had to remove the card lamp board.
With the lamp board out (again) I replaced all the lamps with new 2187 bulbs that run way cooler.
Then I removed the card besel and the pegs that held the card to the shroud. To remove the 4 chromed pegs in the centre of the card. First I had to remove nuts in the back of the shroud, then I had to gently persuade the pegs out with a pair of miniature vise-grips. To avoid damaging the chrome I put some duct tape on the jaws of the pliers. Pro tip ;)
Here's what the front of the game looks like with the bezel and card removed.
Once the card removed I took a few detailed pictures just in case I totally mess up and had to get the card reproduced somehow.
This picture really doesn't show just how badly the card was warped. It was the elephant man of arrangeball cards
As can bee seen from the back of the shroud, the bulbs ran way too hot!
Here's a pinside thread about flattening pinball plastics.
I used that information as a starting point for my experiment.
The trick is to soften the plastic by heating it up, close to the melting point but below the boiling point (That's when you get bubbles in the plastic).
What people fail to consider is that regular ovens suck at controlling temperature. The dial is vague at best and the heat control is awful. The temperature oscillates +20 and -20 degrees celcius from the set point in my oven.
For better control and temperature reading, I used my multimeter that came with a thermocouple
I found two pieces of thick plate glass in my supplies and sandwiched the card in between, then put it in the oven at a low (safe) temperature.
Getting the oven warmed up:
No, I didn't heat the plastic directly on the rage element. I was just illustrating getting ready
The thermocouple supplied with my multimeter.
I slowly and gradually turned up the heat in the oven and continuously monitored the temperature and state of the card. The plastic became soft at a temperature between 110 and 120 degrees Celsius (that's 230 to 250 in Freedom degrees). The card flattened out just with the weight of the glass.
The end result isn't great but at least the card is is flat now. Looks way better. I'm satisfied the result considering the state of the card.
To wrap up this post here's a couple teaser videos of the bonus feature in action.
