I’m still debating whether to build a second rotisserie or not. I still have a couple more playfield swaps lined up after Space Shuttle, but for now I settled on getting a new set of sawhorses at Harbor Freight. The cheap plastic ones are lightweight and wobbly, so for this task I stepped up to their nice steel ones which have a nice, big, flat fake-wood surface. Since they’re made of steel, they are much heavier and more stable than the cheap plastic ones. It’s a decent enough way to get the new playfield off the floor anyway 🙂 Once I’m further along in the playfield swap, the new playfield will go in the rotisserie, of course, but there’s still plenty of work left before that can happen…
Onto the task at hand for today – installing the screws that hold the metal pop bumper brackets under the playfield. There’s three per pop bumper, and as you can see in the picture below, they have machine screw threads as well as wood threads. Obviously, the wood threads go into the playfield and the machine screw threads take the nuts that hold the bracket down.
Thankfully my new playfield already has the holes drilled out for these screws, but unfortunately the holes were too small. Also notice that the factory holes aren’t countersunk – There’s no way the head of the screws can sit flush with the playfield unless some material is remove to make room for the heads. So, after thinking about it for a while and debating which size drill bit to use, I went ahead and enlarged the holes with a 9/64″ drill bit and used a micro-stop countersink cutter to countersink the holes.
The microstop countersink cage allows for drilling very nice countersinks with great consistency from hole to hole. The screws would now fit in the holes, but they still need to be hammered in all the way such that they are flush. I couldn’t picture myself doing this with a regular hammer without hitting the artwork (especially once the screws get close to flush), so I used another aviation tool – a rivet gun with a flush mushroom set:
The painter’s tape is there to prevent scratches on the surface. The rivet gun had no problem at all driving the screw-nails in and they sit perfectly flush! Awesome!
Here’s a view from the underside, where the machine screw ends are ready to accept the pop bumper assemblies.
Alpha Bravo Pinball 