Software for CNC hot-wire cutting and model aircraft design

Wing designer

The heart of wing cores and negative shells. For multi-taper wings you simply add segments; the tip airfoil of one segment automatically becomes the root airfoil of the next.

• Sheeting global, separate for top and bottom, or per segment; optionally as a D-box only, up to a share of the chord
• Align airfoils on chord, highest or lowest point, or hinge line; groups for wings with several kinks
• Global sweep on leading edge, trailing edge or hinge line, also with groups
• Round, oval and trapezoidal spars, cap pockets, I-beam spars, airfoil-following lightening cut-outs and hinge cut-outs (including X-shaped hinge gap and a through slot for a false trailing edge)
• Blended airfoils: a segment automatically mixes between inner and outer airfoil
• Click spars and segments directly in the views, and the side menu follows

Core design

Derives the cores and the press shells from a wing.

• Block margin constant or proportional to airfoil length, type of leading- and trailing-edge extension
• Kerf from the ratio of airfoil lengths or from the local path speed (still experimental)
• Shell cuts: plane the top and bottom shells horizontally during the cut
• Split cores: everything kerf-compensated, the pieces add up to the full core again; allowance for glass sleeve and caps
• Mirror, stack, spar cut-outs with selectable order and a pause to lift off the upper shell
• Leading-edge cut: square pocket or straight cut-off for a glued-on leading edge, in the same pass as the core cut
• Edit points: move, delete or add airfoil points or cutting-path points
• Rotate workpiece: put the wing on the machine's zero line by trailing edge, leading edge or quarter-chord line

Negative shell design

Instead of a core, you cut the two mould halves here, into which you later laminate. Besides worries about an ageing GMFC card, this was one of the main reasons for writing this software: geometries for CFRP shell wings in Styrodur negatives used to be drawn in CAD and later came from an elaborate Excel sheet.

• Cutting path with cut extension (same kerf at the parting surface as in the airfoil cut) or in one pass without pre-cuts
• Mould block height below the material thickness: inaccuracies of the cutting table are evened out and the segments fit
• Kerf goes outward into the material, also displayed at true thickness to avoid collisions
• Cut core and support material in the same pass; this saves a lot of time and material
• Split the core into webs while the shells stay usable; spar cut-outs in the core
• Edit points as in core design

Mould making

Turns the wing into a plug, a split plug for moulding, or directly the negative mould. The module is aimed more at 3D printing; whether it is accurate enough for milling remains to be seen. Export is STL, or STEP for CAD programs.

• Airfoil smoothing with comparison window; loft as ruled surface or spline across all ribs
• Wing tip with presets based on real gliders, winglet with blended transition or from a three-view drawing
• Parting surface, bead, mould edge, resin groove, bump, alignment holes and recesses for the joiner
• Joiner holes and screw fastening at the joint (DIN 7991, DIN 912)
• Segmentation into printable pieces with dowel pins
• Section view, curvature combs, zebra stripes and measuring on the 3D model
• STEP delivers a true, smooth solid rather than a triangle mesh

Rib designer

Derives ribs from the wings, such as root ribs, support ribs or torsion ribs for shell wings. You can also create sanding templates for the leading edge and export them as STL.

• Take the sheeting from the wing or set it separately
• Half ribs; spar cut-outs are carried over
• Root rib can also be skewed to match the fuselage waist
• Export as 3MF with separate parts or STL; hand-over to CAD for DXF

Web heights experimental

Define spar and control-surface webs and read off the height list for each web, every x mm and at every segment joint. Plus top view, front view and sections, with hand-over to CAD editing.

Wing servos experimental

Place servos from a type list, define horn and linkage, view deflection and ratio. The module checks the space in the airfoil and collisions with webs, caps and joiner, and generates the sections through servo and linkage.

DXF shapes

Cuts any contour you like. Each segment has two cross-sections of its own: INNER (left tower) and OUTER (right tower). If both are the same you get a straight body, if they differ a tapered one.

• Load DXF or SVG; each layer is offered as a cross-section, helper layers are only displayed
• Sync points automatically or by hand, the crosshair snaps as in CAD
• Several segments with width, block dimensions and rotation
• Freely selectable entry point and cutting direction
• Take over GMFC projects (.cnc) directly, including segments and sync points

3D model

Slices any model. The slices are cut individually with the wire and then glued back together, for example for fuselages, canopies, fairings or figures.

• Load STL, OBJ, STEP and IGES; flight-simulator models from X-Plane, FlightGear and glTF/GLB are experimental
• Freely choose cutting axis and planes; take outer or inner contours
• Segment-pair view with cutting path and automatically synchronised profiles, sync points also by hand
• Entry point at a fixed angle: the entry slit later serves as an alignment mark when gluing
• Plate: several segments of equal thickness in a single cut, connecting paths run through free space

Cut-outs

Cuts a shape out of a block, for example the wing saddle in a fuselage block. Alternatively, the airfoil remains standing as a piece. The cut-out is a separate source in the G-code tab.

• Airfoil, canopy or rectangle; several cut-outs per project
• Airfoil from the wing, as .dat or from the airfoil database, with scale and incidence
• Segments from DXF shapes or 3D model as reference, one behind the other in position
• Kerf from the calibration, clearance for a good fit, entry from four sides

G-code

This is where the machine program is created: settings on the left, in the middle the 3D simulation with both gantries, wire, block and cutting paths, and the program text on the right. The simulation runs on the real G-code and real feed rates, so the displayed run time matches the machine.

• Sources: core design, negative shells, DXF shapes, 3D model, lettering and cut-outs
• Cutting direction from the rear or the front, right or left wing
• Block cut before, after or during the airfoil cut
• Block position, axis names, your own header and footer
• Feed jumps above 10% are marked in red
• Edit G-code by hand or load and simulate files from other programs

Cutting

This is where the actual work on the machine happens. The simulation serves as a last check before cutting, with position and manual jog below it. Before starting, the program checks that all travel and feed rates are within the machine's limits.

• Block preparation: guillotine, trim to length, horizontal block cut
• Kerf calibration: two test cuts for kerf against feed rate, optionally a third to adapt the wire heating
• Pause or abort at any time, then return to zero
• The E-STOP button does not replace a real emergency stop on the machine

Machine

This is where you connect to the board. All GRBL parameters can be set in the side menu and are transferred directly to the board. Machine data such as tower spacing and maximum travel go here too; the correct tower spacing (distance between the wire mounts) is important. Manual control and zeroing the axes are also here.