Phase 10: Clearance, Clarence

A project log for SWD-40: a 40% scale Special Weapons Dalek

Yes, I'm a sci-fi geek.

jorj-bauerJorj Bauer 10/18/2016 at 02:230 Comments

With the motors mounted up on the base plate, and some quick measurements done, it was clear that the wheels wouldn't quite fit inside the model. As the walls slope up, and the ping pong balls encroach on the interior, they fouled the path of the wheels. Not enough clearance.

Well, I'm not ready to give up on this plan just yet. I figured all I needed was about three quarters of an inch. Which just so happens to be the thickness of the plywood I'm using for the base of this build. So, a quick trip down to the basement^H^H^H^H^H^H^H^H woodshop: remove the motors and casters again, trim down the base I've got so it's slightly smaller than the current base of the model (matching the original lower base plate, which obscured the motors); grab some spare plywood and trace out another of the same dimensions (more or less; done by trace-and-eye); cut a larger rectangular hole in the middle of the new plate; and blammo, we've got a quick shim layer. Close enough for the moment. If this works out, I'll have some finishing woodwork to do though. (If I only had a radial arm saw. Or room to put one in my house. Sigh.)

As i'm re-mounting the wheels, here you can see the channel down the center of where the wheels mount to the base.

And here it is, assembled.

I also cut out a prototype foam core box to enclose the wheels - the beginning of the structure to hold the circuit boards, controllers, power circuitry, and battery. I'd actually done this before the shim layer, and this is how I knew there wasn't enough clearance: I couldn't fit the box inside the model. So now with the base being a little taller, I cut 3/4" off of the box...

... test fit it over the wheels ...

... and the box *still* doesn't fit inside the model. Too wide near the front; there's just not enough room between the wheels and the inside sides of the Dalek (where it narrows). I'll worry about that later! For now, let's take the box off and see if the wheels fit as planned...

Presto! Nice. Looks like I've finally got a way to attach the wheels to the model. Looks like I also could have gotten away with less than 3/4" - maybe 1/2" on this side. I'm not gonna fight that, though.

Now, I still have to take that apart again and clean up the woodworking so the two have a clean, consistent outer edge; sand the heck out of it (the actual base has several layers of bondo to smooth them out, and I'm not planning on doing that with these layers); prime; and paint gold. It won't be perfect. The wheels and casters are tall enough that you can see each of the casters in the front and back, which I don't want. Maybe if I add another layer of trim on the bottom... well, that's a problem for another night.