The game
The plate stands upright. A bar lies across it, hanging from two strings, and each string runs up to a motor in one of the top corners. The marble rests on the bar. By running the two motors at different speeds you tilt the bar and lift it, rolling the marble left and right as it climbs. Roll it over a hole and it drops through. Steer it past every hole into the goal at the top and you've won.
This tool makes the plate, and a base to stand it in. The bar, the motors and their mounts are up to you.
Plate size
Width and height are the outer size of the plate, 200 × 300 mm by default, and each can be anything from 80 to 1000 mm. A bigger plate fits more holes and longer side text.
Motor holes & strings
There's a motor hole in each top corner, Ø 5 mm with its center 15 mm from the top and 15 mm from the side by default. Change all three under Advanced settings to fit your motors.
The strings hang straight down from the motor holes, so the designer treats a vertical line under each one as the string. It keeps the holes away from those lines (see below) and puts the side text outside them. In the preview the strings are drawn as dashed lines; they're not in the file.
The holes
You choose how many holes you want and their diameter (20 mm by default). They're placed at random, but within these rules (all under Advanced settings):
- Clear of the strings — no hole edge closer than this to a string line (10 mm by default), so the bar can always run up the sides.
- Min. gap between holes — the smallest distance from one hole's edge to the next (10 mm by default), so there's always some bar to roll on between them.
- Start zone at the bottom — a band with no holes where the bar rests at the start (40 mm by default). Its top edge is the dashed line across the preview.
- Below the goal — the goal is the only hole in the top row; the others start one hole and one gap below it.
The holes are spread out rather than clumped: each new hole goes in the free spot farthest from the ones already placed, picked from a handful of random tries. If you ask for more holes than fit, the designer places as many as it can and tells you how many that was. With the defaults that's around 22. For more, use smaller holes, a smaller gap or a bigger plate.
The goal
The goal is a hole the same size as the others, 10 mm below the bottom of the motor holes, at a random spot from left to right. By default it gets an engraved ring 3 mm outside its edge, so players can see which hole to aim for. Untick Engrave a ring around the goal hole under Advanced settings if you'd rather mark it yourself, e.g. with an LED. It's tinted green in the preview only.
Random layouts & seeds
Generate new layout makes a new random arrangement. Changing the plate size, the number of holes or any spacing keeps the same layout as far as possible, so you can tweak a board you like without losing it.
Every layout comes from a number called the seed, shown as “Last seed used” under Advanced settings, and in the downloaded file's name. To get a layout back later, click Use this seed or type the number into the Seed field, then click Generate. The same seed with the same settings always gives the same board. Any text works as a seed too.
Text up the sides
Each side gets its own line of text, engraved in the strip between the plate edge and the string, reading from the bottom up. It runs from just below the motor hole to just above the bottom edge, with 3 mm clear all round, and is scaled as large as it fits. With the defaults the strip is 9 mm wide, so letters come out at most 9 mm tall; a long text gets smaller to fit the length. Move the motor holes further in to make room for bigger letters.
The font is Bungee, which only has capital letters, so lowercase comes out as capitals. Characters it doesn't have are left out, and a warning lists which ones. The engraving is a line around each letter; fill it in your laser software if you want solid letters. Leave a field empty for no text on that side.
Hole rings
The plate's file also has three hole rings, next to the plate: a ring with the same hole as the plate's holes (it follows the hole diameter), about 3 mm of material around it, and two ears on top with Ø 3 mm screw holes. Under Advanced settings you can change how many there are (0 for none) and the size of the screw holes.
The base
The base is a small box with a sloping top, for the controls, and the plate stands behind it. The box's two side plates run on behind it, lower, with two slots cut down into them as wide as the plate is thick. Stand the plate in the upright slot, or in the leaning one to have it lean back (10° by default).
Width, box depth, front height and back height are the box's outer sizes (160 × 70 mm, 50 mm at the front and 60 mm at the back by default). The plate goes through the slots in both side plates, so it must be at least as wide as the base; a wider plate just sticks out at the sides. The bottom of the plate sits behind the box and can't be seen, Looking down over the box while you play, you see about 10 mm more than a level view would, so the designer warns if the start zone is lower than the box minus those 10 mm — 40 mm with the defaults.
The box is put together like the LED box: the front, back and bottom have tabs that go into the side plates and into each other, and every joint starts and ends with a gap, so the pieces at both ends keep the corners. The tabs are few and big: one per joint into the sides, and two along the width between the walls and the bottom (1–3 under Advanced settings). Each tab is twice as long as the gaps around it. Where the side plate carries on behind the back wall, the back wall's lower tabs go into closed slots in the side instead of notches in its edge. The sloping top rests on the front and back walls and is held by tabs into the sides — glue it, or leave it loose to reach what's inside.
The top has two button holes, Ø 25 mm by default, a quarter of the width in from each side and 15 mm from the front edge (measured to the edge of the hole). Above each, toward the back, is an engraved label (LEFT and RIGHT by default, or your own text; leave a field empty for none), set far enough from the hole that the button's collar doesn't cover it: the text starts 20 mm from the middle of the hole, which clears a collar up to about 33 mm across. Change the hole size and both distances under Advanced settings, or untick Two button holes in the top for a plain top. In the file the top is drawn the way you'll see it from the front, front edge at the bottom.
The back wall has a small wire hole at each end, Ø 3 mm by default, for the cable from the motor on that side. Each sits 2 mm from the inside of the side wall, with its center 8 mm above the bottom: the cable comes from behind the plate, so it runs low, under the slots. Change the size under Advanced settings.
Under Advanced settings you can set the material thickness, kerf and number of tabs along the width for the base, and how thick the plate is — that's the width of the slots. You can also set how long and how tall the part behind the box is, how deep the slots are, where each one sits (measured from the back of the box to the front edge of the slot, at the top) and how far the leaning one leans. Kerf works as in the LED box: every outline is grown by half the kerf, so tabs and slots come out at their drawn size.
Downloading
The plate and the base are separate files, each with its own download button. Pick SVG or DXF with the ▾ next to either button; the choice applies to both. Both use the same lines: black = cut through, blue = engrave (in DXF, on the layers CUT and ENGRAVE). The engrave lines come first, so they run before the holes and the outline are cut.
The plate's holes are drawn at their nominal size, and there's no kerf compensation on the plate, so they come out about one kerf wider than set — usually a tenth of a millimeter or two. If your motor shafts need a tight fit, set the motor hole diameter a little smaller.
About
This tool was built for Reaktor 51, a makerspace in Trondheim, Norway, by one of its members. “Elevator maze” is a working name.