Bin frame — Bottom interface

Bottom interface

How-to guide

The component the chute rests on top of.

Author Spencer

Contributors Abrianbaker, BrickCycleAlice, barthel, Daddy-O's Bricks - Bill and Danny

Parts needed

Bearings

Printed parts

Heat inserts

Screws

2× 8mm
8× 16mm
9× 16mm

Nuts

A an interchangeable alternative works (hover for what).

Tools needed

Hex keys, 2 mm for M3 and 2.5 mm for M4, plus 3 mm for an M5 button head or 4 mm for a socket head
Soldering iron or heat-set insert press
Drill or electric screwdriver

The bottom interface is the Lazy Susan bearing assembly the chute rests and spins on, slung underneath the bottom layer's frame.

Build it on the bench whenever you like, but fit it last. It is the Lazy Susan the bottom of the chute stack sits on, so it goes on once the frame is standing and the chutes are in.

This assembly has no frame of its own. It hangs under the bottom layer's hex frame, built on bottom layer, so you don't need an extra one. Steps 5 to 10 work on that frame's spokes, from underneath.

A finished hex frame from above: six B spokes and their printed crossbeams forming the inner ring inside the aluminum outer hexagon, with a printed corner bracket at each of the six vertices — A finished hex frame. Photo: BrickCycleAlice.

The parts list above is only the Lazy Susan bearing stack and the extrusion mounts added in steps 5 to 10, and its fasteners are called out inline at each step.

Fastener icons match the parts list: the silhouette is the head shape, the colour is the thread size. M3 M4 M5 M6

Video: Basically's own YouTube channel. Who filmed it isn't recorded.

The bottom interface stacks the chute mount, the Lazy Susan washer, the Lazy Susan bearing, and the bottom static part. The Lazy Susan itself is two discs, inner and outer, that spin independently: the chute mount screws to one disc and the bottom static part to the other. Here it is exploded into its components:

Exploded view of the bottom interface: chute mount on top, Lazy Susan washer, Lazy Susan bearing, and the corner mounting brackets below — Exploded view. Render: Adrianbaker.

Close-up exploded view of the bottom interface parts separating from the mounting brackets — Detail of the same exploded view. Render: Adrianbaker.

Once assembled, it mounts into the machine frame:

The bottom interface assembly mounted into the aluminum extrusion machine frame — Look at the middle of this one, not the corners. Diagram pictures courtesy of Adrianbaker in the basically Discord.

The corners in that render are out of date. It shows an ordinary bottom vertical and cover at floor level with the caster under it. On a build, each bottom corner takes the External bracket — foot cover, and the extrusion is piece D, running down through the corner to the foot connector the caster screws into. See bottom layer, steps 1 to 3. The Lazy Susan mounting in the middle of the render is right.

Step 1 Preparation

Press the heat inserts into both printed parts while they are still loose. See installing heat inserts for the technique.

Lazy Susan chute mount: 4 × M4, evenly spaced around the circular mounting face.

Looking into the Lazy Susan chute mount's circular face: four brass M4 heat inserts around the rim, with the raised square socket for the chute in the middle and the pass-through hole between two of the inserts — All four M4 inserts, with the pass-through hole. Photo: BrickCycleAlice.

Lazy Susan chute mount: 2 × M3 for the layer connectors, one on each side face, on the small raised tab about halfway up.

Render of the Lazy Susan chute mount's side face, with a red circle around the small pocket on the raised tab partway up the wall — The pocket on the near side face. The far side is a mirror of it. Render: Balloon.

Close photo of the same raised tab on a printed chute mount, with a red circle around the empty pocket in it — The same pocket on a printed part, empty. Photo: BrickCycleAlice.

The same raised tab on the chute mount with its brass M3 heat insert pressed in flush — And with the insert in. Photo: BrickCycleAlice.

Lazy Susan bottom static: 4 × M4, evenly spaced around the top face.

The flat Lazy Susan bottom static ring from above, with all four M4 heat inserts and a hole between two of them — The bottom static ring, all four inserts visible. Photo: BrickCycleAlice.

Printed parts elsewhere in the machine take inserts too. Each assembly page lists its own in a Preparation step like this one.

Step 2 Mount the Lazy Susan to the chute mount

This step and the next work on opposite faces of the same bearing.

Remove the Lazy Susan's rubber tabs first (see Preparing Lazy Susan). The washer goes on before the bearing: set the Lazy Susan washer on the chute mount, then the Lazy Susan on top of that.

A thumb holding the Lazy Susan washer in place on the chute mount, before the bearing goes on top — Holding the washer in place before the bearing goes on. Photo: BrickCycleAlice.

Line up a hole in the disc with one of the chute mount's inserts, drive an M4 × 16 mm countersunk screw, and repeat around the disc.

Close-up down an aligned hole in the Lazy Susan, with the brass M4 heat insert in the chute mount visible at the bottom of it — Lined up: the brass insert sits at the bottom of the hole. Photo: Spencer.

Driving a countersunk screw through the Lazy Susan into the chute mount — Photo: Spencer.

The M4 × 16 mm countersunk screws must be very tight. A drill or electric screwdriver will not get them there, so finish them with a hex key by hand. Machine vibration works a loose one out of a spot that is a hassle to reach later.

The Lazy Susan bearing bolted onto the chute mount, seen from above — Bolted on. Photo: BrickCycleAlice.

Side view of the bolted assembly with the thin white Lazy Susan washer visible sandwiched between the bearing and the chute mount — Side view, with the washer visible between bearing and mount. Photo: BrickCycleAlice.

Step 3 Mount the Lazy Susan to the bottom static part

The bearing's other disc screws down into the bottom static part. All four of those screws go in through a single pass-through hole in the chute mount, rotating the assembly between each one.

Lazy Susan hole aligned with the pass-through hole, seen from the top — Seen from the top, with the bearing hole over the pass-through. Photo: Spencer.

Pass-through hole in the chute mount with the screw reachable underneath — The pass-through hole in the chute mount. Photo: Spencer.

Set the chute mount and Lazy Susan assembly onto the bottom static part, then line up the pass-through hole with the insert marked by the red square.

Placing the chute mount and Lazy Susan assembly onto the bottom static part — Photo: Spencer.

Pass-through hole lined up over the heat insert, marked with a red square — Lined up over the marked insert. Photo: Spencer.

Drive the first M4 × 16 mm countersunk screw through the pass-through hole. Don't tighten it fully yet, leave some play while you get the rest of the four seated.

First screw driven through the pass-through hole — Photo: Spencer.

Rotate the chute on the Lazy Susan, the way it turns in normal operation rather than forcing the whole assembly, to bring the pass-through hole over the next insert. Repeat for all four screws, then tighten all four the rest of the way.

Rotating the chute with the Lazy Susan to the next screw position — Photo: Spencer.

Pass-through hole lined up over the next heat insert after rotating — Pass-through hole now over the next insert. Photo: Spencer.

The bearing stack is now complete:

The completed bottom interface with chute mount, Lazy Susan bearing, and bottom static part assembled — Photo: Spencer.

Step 4 Add the two layer connectors

A Layer connector A and a Layer connector B go onto the chute mount, one on each side face, into the two M3 inserts pressed in step 1. One M3 × 8 mm countersunk each. They are the same pair that joins every chute to the one above it; here they are what the bottommost chute lands on.

With them on, the bearing stack is complete: chute mount, Lazy Susan, washer and bottom static, plus the connectors that carry the layer above.

The finished bearing stack: the square chute mount standing on the round Lazy Susan and bottom static, with a layer connector bolted to the raised tab on each side face — The completed stack, both connectors on. Photo: BrickCycleAlice.

Step 5 Bolt a hold in place to each mount

Bolt a hold in place onto each mount with one M5 × 16 mm socket / button head , before either part touches the extrusion.

A Lazy Susan extrusion mount lying on a bench with the hold in place standing on top of it and a stainless M5 button head part way into the hole through both — Driving the screw through the hold in place into the mount. Photo: Danny.

Three views of the same printed part on a white background: the Lazy Susan extrusion mount with its hold in place bolted under it, a grey wedge with a triangular window through its web and counterbored slots along its bottom face — The bolted pair, from three angles. Photo: BrickCycleAlice.

Step 6 Prestart the T-nuts

Drop an M5 × 16 mm socket / button head through each of the mount's two counterbored holes and start a M5 T-nut on the end, two or three turns. Leave them loose enough to swing. See Fitting T-nuts for how they go in.

The mounting face of the extrusion mount, with two roll-in T-nuts started on screws and standing proud of the surface — Both nuts started, still loose. Photo: Danny.

Looking down the mount's two counterbored holes at the button heads of the screws sitting in them — The same two screws from the other side. Photo: Danny.

Step 7 Slide the mount onto the spoke

Slide the mount onto a B spoke (158 mm) already in the frame, T-nuts into the extrusion slot. Push up on each nut with a screwdriver as it goes, so it seats square.

Close view of the two prestarted T-nuts lined up with the open end of the 2020 extrusion slot on the spoke — Nuts lined up with the slot. Photo: Danny.

The extrusion mount sitting in position along a spoke of the hexagonal frame, with both T-nut screws still standing proud — In position, screws not yet tightened. Photo: Danny.

Step 8 Tighten

Tighten both M5 × 16 mm socket / button head screws into the T-nuts.

An electric screwdriver driving one of the two screws in the top face of the extrusion mount while it sits on the frame — Photo: Danny.

The mount and its hold in place seated down onto the spoke's extrusion, seen from the outside of the frame — Seated down onto the extrusion. Photo: Danny.

Step 9 Repeat for the other two mounts

Nine M5 × 16 mm socket / button head and six M5 T-nut across all three.

Step 10 Lower the bearing stack onto the mounts

Set the bearing stack from steps 1 to 4 down onto the three mounts, so the Lazy Susan bottom static part lands in the triangular cutouts.

Nothing screws it down. The cutouts hold it in position, and the weight of the chute stack that hangs from it afterwards keeps it seated.

The finished result

The bearing stack sitting in the three mounts, ready for the chute core. With a funnel fitted, it lands level with the bin entrances.

Photo from underneath the bottom layer: the bearing stack down in the three extrusion mounts, both layer connectors on it.

Top-down view of the assembled hexagonal layer frame with three Lazy Susan extrusion mounts fitted at alternating spokes — The three mounts around the ring, before the bearing stack goes in. The frame is off the machine here, not in its built orientation. Photo: BrickCycleAlice.

The Bin frame page contains the instructions for the entire stack, and is where you should return once you're done here.