Copy Stand Base Plate

A parametric, 3D-printed copy-stand base sized for a Bambu Lab X2D and designed around a Lobster Holder V2.1 on its CS-Lite. The base uses a removable 2020 extrusion socket, adjustable 1/4-20 feet, and an optical-breadboard-style 1-inch grid of heat-set inserts.

The structural parts are intended for black ASA. Grid lines are flush blue ASA inlays printed against a textured build plate.

Coordinate system and principal dimensions

Base: 203.2 x 248 x 15 mm, with 12.7 mm corner radii.
The grid origin is Y=0 and positive Y runs toward the operator. The socket flange's straight front reference face is Y=12.7 mm (0.5 inch), halfway between the origin and the first insert row. The extrusion's front face is aligned to Y=0, so either reference can be used for direct measurement.
The 8 x 8 insert array has 25.4 mm spacing. Its rows are Y=25.4 through Y=203.2 mm relative to the socket datum.
A blue Y=0 datum line continues beneath the socket, leaving aligned visible segments on both sides.
The removable socket captures 50 mm of a nominal 20 x 20 mm extrusion.
Its 110 x 38.7 x 10 mm flange reaches from the rear plate edge to the half-inch reference face. The collar is near the flange center, with tapered side gussets that retain the original broad flange footprint.
The two outside inserts in the front grid row also mount the front leveling feet. They cannot accept top-side accessories while the feet are installed.

Hardware

Qty	Item	Relevant dimensions
70	McMaster 97171A240 brass 1/4-20 heat-set insert	9.525 mm body, 12.7 mm flange, 1.27 mm flange thickness, 8.026 mm maximum hole
4	1/4-20 adjustable foot	19 mm pad diameter, 8.5 mm pad height, 17.8 mm stud
4	Knurled 1/4-20 locking nut	24.4 mm OD, 6 mm thick
1	European-style 2020 T-slot extrusion	20 x 20 x 400 mm, 6 mm slots
4	1/4-20 x 1-inch socket-head screws	Socket flange to base
4	Black 1/4-inch flat washers, specified as 0.7 inch (17.78 mm) OD	Load distribution beneath socket screw heads; measure thickness before assembly
4	M5 x 10 mm socket-head screws and European 2020 T-nuts	Extrusion clamp; verify screw length against the selected T-nut

The four feet use four of the listed inserts: two dedicated rear inserts and the two shared front grid inserts. Four more dedicated inserts secure the socket. The remaining 64 inserts make up the complete grid.

The McMaster drawing requires at least 0.530 inch (13.46 mm) of material. Every insert boss in this design is 15 mm tall, including all four socket-mounting bosses. The 52.5 x 22.5 mm locating slot passes through the base between those bosses, so it does not reduce their thickness. Inserts install from the open underside with their flange flush against the boss. The 1.35 mm flange seat and 9.525 mm body leave a 4.125 mm screw-clearance tunnel below the clean 6.8 mm opening in the working surface.

Build

Requirements: OpenSCAD 2021.01 or later, Ruby, and Python 3.

ruby build.rb

The build is incremental. Run REBUILD=1 ruby build.rb to regenerate every component after changing geometry parameters.

Generated files are placed under exports/3mf and exports/stl. The primary files are:

base_multicolor.3mf: aligned black base and blue inlay meshes, assigned to filaments 1 and 2.
socket.3mf: removable black socket and gusset assembly.
coupon_multicolor.3mf: two-piece insert, rail-clearance, through-key-fit, and line calibration coupon.
coupon_key.3mf: standalone full-size tongue gauge from the two-piece coupon.

The portable multipart files intentionally do not embed a printer or process profile. The individual aligned meshes and single-color fallbacks are retained alongside them.

Calibrate before the full base

Print coupon_multicolor.3mf in the intended ASA, face down on the intended textured plate. It produces a main coupon and a separate full-size tongue gauge. From left to right, the insert pilots are 7.70, 7.85, 8.00, 8.15, and 8.30 mm. The four rail gauges are 20.0, 20.1, 20.2, and 20.3 mm. Each is a four-wall collar with the production 6 mm side walls, 2.7 mm end walls, and full 50 mm engagement depth. External gussets and M5 holes are omitted because they do not define the rail-fit surfaces. The coupon also contains the production-width blue line and a 6 mm-deep 52.5 x 22.5 mm through-slot. The separate 52 x 22 x 6 mm tongue is an XY fit gauge for the production interface; its shorter depth keeps the calibration print compact. It has a support-free stop shoulder and vertical grip for insertion and removal. Verify that the slot is visibly open, with no first-layer membrane, before testing the fit.

The production model defaults to the physically calibrated 8.10 mm insert pilot and 20.1 mm rail cavity. These values were selected from an ASA coupon: the 20.1 mm collar accepted the fully cooled rail through all 50 mm by hand without objectionable play, and the 8.10 mm pilot provided the preferred insert fit. The rectangular tongue and through-slot also passed the physical XY fit test. The production tongue retains those dimensions and extends 14.8 mm into the 15 mm base, leaving 0.2 mm underside clearance. For another printer, material, or process, select the smallest rail gauge that fits without forcing and use the insert pilot that gives the required installation grip. Change insert_pilot_diameter or rail_clearance at the top of copy_stand.scad, then rebuild. The 8.30 mm coupon remains a diagnostic oversize option; McMaster specifies 8.026 mm as the maximum nominal hole diameter, while this design's 8.10 mm production value reflects the tested print process.

Bambu Studio setup

Open base_multicolor.3mf as one multipart object.
Assign black ASA to Filament 1 and blue ASA to Filament 2.
Keep the 248 mm dimension along the printer's Y axis and place the base to one side. Its 203.2 mm X width leaves about 52.8 mm for a nominal 35 x 35 mm prime tower and clearance.
Confirm the tower and any brim fit in Preview before printing.
Print the base face down. No support is designed into the base, socket, or coupon.

The coupon occupies approximately 228 x 110 x 53.2 mm including its separate tongue and full-depth rail collars. Orient its 228 mm dimension along Y to leave ample X space for the prime tower.

A 0.4 mm nozzle and 0.20 mm layers are the compatibility target. Use at least six walls, six top and bottom layers, and 40-50% gyroid or cubic infill for the socket. Use at least four walls for the base, suitable ASA bed adhesion, a fully heat-soaked enclosure, and conservative cooling. The modeled open cells provide the base structure; sparse slicer infill is not relied on there.

Assembly

Heat-set the inserts from the underside. Stop when each brass flange is flush with its counterbore; do not pull it toward the textured top surface.
Thread the leveling feet through their locking nuts and into the two rear foot inserts and two outer inserts of the front grid row.
Lower the socket's 52 x 22 x 14.8 mm tongue into the base's through-slot, then fasten the flange with four 0.7-inch OD washers and four 1/4-20 x 1-inch screws. The screws provide clamping and vertical retention; the tongue provides repeatable X/Y location and carries lateral shear. With a washer thickness t in millimeters, nominal insert engagement is 11.275 - t mm, limited by the insert's 9.525 mm threaded length.
Preload two T-nuts in each side slot of the extrusion. Lower the extrusion to the socket floor and fasten it through the four M5 clamp holes.
Level the base, then tighten each knurled locking nut against its insert flange.

The Lobster/CS-Lite locating fixture, Arca rail, camera carriage, and camera alignment accessories are deliberately deferred. They can attach to the grid without changing this base.

The socket's tapered side buttresses follow the collar at their upper edges while retaining the original broad footprint on the flange. They stop before the four base screws. Vertical 19 mm washer and tool envelopes preserve access above those screws, and 14 mm horizontal tunnels provide driver access to the M5 rail clamps without sacrificing the collar wall around the T-slot extrusion. The 19 mm fore/aft screw-row spacing and broad flange attachment improve overturning and torsional resistance compared with the compact first revision.

Before mounting a camera, proof-test the assembled stand with a dummy load at the maximum working overhang. Under the normal payload, target less than 1 mm of rail-tip motion. After 24 hours at twice the intended payload, require no cracking, washer embedment, or loose fasteners and less than 0.25 mm permanent rail-tip displacement after unloading.

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