I'm keeping my comments to only the best of the best projects. Right now, this is it.
Wow, thank you. That's better than a UCA.
Bah, it does nothing but rain where I am, stuff like this keeps me checking in to BYOAC and thinking of my own projects.
I'm glad this is a comfort to you. If my thread indirectly contributes in some small way to more Ond cabinets existing, that's extremely worthwhile. Malenko also mentioned enjoying this detailed format, so I'm going to keep at it.
In today's episode, I learn a valuable lesson about trust from Mr. Forstner Bit.
I'm going to have a metal plate, about 3" x 4.5", on the front face of the back cabinet, with connectors on it. This plate will host a DB 15 that goes to the retracting control panel, a DB 25 that goes to the front cabinet, and probably a second one of each in the other polarity to account for the to-be-built limit switches, actuator signal lines, flipper buttons and vpin toys. (The connectors are for me being able to transport the thing from my shop to the room it'll live in, which I think is going to take about five trips, so I'm building it to be a bit modular.)
I probably should have cut this before painting and polishing, but, no problem. I'll just use a forstner bit - they make beautiful consistent holes with finished sides in my experience.
My via is going to be taller than it is wide, I plan to use two overlapping forstner holes with a bit of cleanup to connect the sides together afterward to make a round-ended capsule shape.
First, I predrilled the centers all the way through from the back with a small drill to make a pilot for the triangular point to follow and to transfer the location onto the front face so I could see it.
These pilot holes are on 1 1/2" centers, so the biggest forstner I've got at 2 1/8" for a 1 1/16" radius won't clip the other hole's pilot location.
I chucked up my big forstner, and here I am ready to go.
You can see the pilot holes on the front face, to the left of the bit.
I figured I'd cut into both pilots from both sides fairly evenly, taking turns in all four locations. I cut from inside the box first, just skimming the paint off and starting the circle, high and low, and then did the outside high and low. Back to the inside, and the high hole did something I've never had happen before - the pilot hogged out to the left and the whole circle shifted sideways.
A forstner of this size in a hand drill is not so stable and clean as every prior experience I've had with them. I shoved it hard to the right while cutting and managed to reestablish the hole back where it belongs, but you can see the crescent of accidentally destroyed surface there.
That was sobering.
Okay, these things aren't as safe and precise as I expected. I decided at this point on a new plan: if they're not completely predictable, I'm going to continue doing most of the cut from the inside of the box, where any damage will be less apparent. There's going to be a metal plate covering the outside of the hole, sure, but any damage extending further than the plate overhang, would show in the end.
I've basically crawled half inside the back cabinet, working from behind the machine, and I'm carefully drilling the two holes from the inside, cutting toward the outside... when all of a sudden the bit grabs like I've never had a forstner grab before, and I hear a mighty crack.
I pull the bit out, and I find this.
I don't even want to walk around to the front of the machine. For a long moment, I suffered that same irrational magical thinking as happens sometimes when you injure yourself - if you don't look, it won't hurt, right?
That's a thick, thick splinter. That tore out a LOT of wood. I just don't even want to look.
But no, that line of thinking doesn't actually work. So I walked around to the front with a heavy heart to see how bad it was.
Here's what I found, from the front.
Amazingly, that shallow cut I'd done from the front was enough to stop the crack from propagating across the edge. How lucky is THAT. The whole perimeter of wood I need is still sound.
I sat down and caught my breath for a bit, and decided I've learned a valuable lesson about trusting very large forstner bits in plywood. I was disinclined at that point to even touch the hole again with the forstner - I got off lucky, I'm not pushing my luck.
The safest way to salvage this mess seemed to me to be my dremel, and a burr cutter.
So I spent a good hour excavating out to the edge that way.
I flipped over to a little drum sander on the dremel after getting both the cores out, and smoothed it back to the line, and removed the rest of the points between the holes. I think this counts as a total save - the end result looks almost as good as I'd hoped in the first place:
Considering I'd planned almost half an inch of overhang of the plate on all sides beyond the edges of this hole to cover for imperfections, I'm feeling pretty good - this will do. It could have gone so much worse, and for a minute there I thought it had.
Zooming out a bit to put it in context with the rest of the rear cabinet, here's the big hole after cleanup, ready to get the edges painted black:
I can live with that. It'll do, especially with a plate over it.
There will be two big structural features near here that connect the front and rear cabinets - a back wall web to the left along the left edge, and a roughly 1x8" shelf that goes below the bearing block, but above this cable via panel.
My next couple steps from here will probably be to tune the position of the TV tray on the axle to get the front gaps right, measure and trim the axle to exact length to get the rear gaps right, and then I'll know the true distance between cabinets to build those two structural features. Once those are built, Shapeshifter will be able to free-stand and self support, and I'll be able to play with the playfield counterweight and screen rotation actuator in earnest.