Pinball Update: Cheap Piece of Mind

I found a web page dedicated to Mars Trek owners. One gentleman in Australia posted a picture of his back glass that had been cracked during transport. He's been looking for a replacement for 15 years.

A cracked back glass won't effect how the pinball machine works, but I think it would greatly reduce the resale value. When the guys at the Internet Pinball Machine Database rate a game, the first thing they grade is a machine's artwork.

Sure, art is subjective, but nobody appreciates broken glass.

Char recently had a friend over, and they were playing in our basement. When Char offered him a plastic ball, he roared like a monster and slapped it out of her hand. The ball sailed across the room and bounced harmlessly off the wall. The ball didn't even come close to my back glass, but it freaked me out a bit.

I can't keep Char from playing downstairs, and I know accidents happen (especially mine), but maybe a little extra protection could help my worst-case scenario anxieties. 

I measured the back box and it's 30 inches wide and about 27 inches long. I found a clear sheet of acrylic that measured 36 x 30 inches (.093 inch thick) for $24 at Home Depot. The manufacturer says that the acrylic is 20 times stronger than glass. Sounds good to me.

I did my best to cut the acrylic into the correct length, but I messed it up some. Luckily, you can sand the edge into sometime more presentable. Here's the cut sheet.

I had a few ideas of how I was going to mount the acrylic to the back box, but instead of making brackets I opted to drill two small holes in the plastic, and I hammered two small nails into the top front of the back box. You can see that the cabinet is a bit worn after 38 years, so I don't think two small nail holes will hurt anything. They can be easily filled and painted. The back box could use a touch up anyway.

The front of the back box angles away from you as it descends, so I used sticky tact to keep the bottom of the plastic sheet attached to the box.

Here's the back box with the protection sheet installed. See, the nails are tiny.

And here's the back box without the protective layer.

The acrylic sheet is almost invisible, and when my father-in-law was pointing out which number he matched, he smacked the plastic hard with the wedding ring on his left hand. But the glass was safe!

I don't plan to keep the sheet on the box 24-7. There's a chance that heat or humidity could be trapped behind the plastic and do unintended damage, but when we have kids running around the house I'll hang it on the machine.

Maybe all of this is silly, but since it makes me feel better, it already works.