1. Load

Open or drop the prosthesis STL from your CAD software, or press Try the demo.

2. Select channels

Look into a channel and click its wall. The wall turns gold as far as the next sharp step. Click the wall past the step to add it. Do this for each channel. If the selection takes too much or too little, change Selection spread and click again. Move the pointer over the model to see what a click will take. Select takes one part of a channel (the click stops at a sharp edge). Whole channel takes every part of the channel in one click, up to its opening. To remove a part, hold Alt and click it (on a touch screen, press and hold it), or use Exclude.

3. Set clearance

Positive values loosen the fit. Negative values tighten it. Uniform moves every selected surface. Radial only moves the walls and keeps the seat height. Keep Rim blend at hard edge for a true parallel offset. Type a value or drag the slider.

4. Export

Saves a new STL named with the mode and value. Your original file does not change. Only the selected surfaces move, so the triangle count and every other face stay the same.

Finding your number

Print the same case at 0, +0.030, +0.060 and +0.090 mm in one job and seat real ti-bases. The lowest value where every channel seats without force is your number for that printer and resin.

1. Load

Open or drop the scan, as STL or PLY (the scan's color is not used). Open scans are fine; you close them in Close scan.

2. Repair

Optional. Fix all turns every piece of the scan to face outward; Flip a piece turns one piece you click. Loose bits removes small specks floating apart from the scan, up to the size you set; the main scan is never removed. To cut something away, such as a tooth, mark it with Grow (click the tooth; the mark stops at the gum line), the Lasso (tick Through to mark the hidden side too) or the Brush, then press Delete marked. Open borders show as lines: gold under the size you set, grey above it. Click Close a hole and then a hole, or close every small hole at once. New surface is smooth and follows the scan around it. Undo goes back three steps.

3. Insertion direction

Turn the model so you look straight down the path the part goes on, then press Set from view. The gold arrow shows the direction. Show undercuts marks in red the surfaces that would lock the part in that direction.

4. Trim edges

Optional. Draw around messy scan edges and remove them. Click points, or press and drag to draw. On an open scan the cut is exact and nothing else is rebuilt. On a closed scan the cut also goes in at once, from the near side to the depth you set; it leaves a hole that you close in Repair.

5. Close scan

Adds straight walls, a land and a flat base under the scan. Drag the base plane or type its height. The scan inside the outline keeps its own triangles. A full 360 scan with only small holes does not need this step: close its holes in Repair.

6. Attachments

Beta. For bars in the scan: find the rail, add clips and slide them along the bar, and give the bar clearance.

Locator housings: each screw channel gets a plane at its opening. Click a plane to place a housing on it, at that height and on the channel's own angle; − and + move it 0.05 mm. For a bar with no hole, use Place on a stud or pad. Build joins the housings to the model and blocks them out straight down the insertion direction.

7. Paint offsets

Pick a zone, give it a value in mm, and paint it with the brush. The brush turns on when you open this step; use Rotate to turn the model. Keys: B brush or rotate, 1-8 zones, E erase, [ and ] brush size, Ctrl+Z undo.

8. Build offsets

Builds the model with your painted offsets. Areas you did not paint, fill or trim keep the scan's own triangles. Painting after a build sets the built model aside; Undo brings it back.

9. Undercut blockout

Fills undercuts along the insertion direction so the part slides on and off. It works on the built model, so the edges of every offset are blocked out too.

10 to 12. Hollow, inspect, export

Hollow makes an even wall with an open base so resin drains. Inspect colours the surface by the space you got and has a probe and a caliper. Reduce (optional, just before Export) makes the file smaller within the accuracy you set and keeps edges clean. Export saves the STL.

Right-drag to rotate (in every step), drag with both buttons, Shift+drag or the middle button to pan, scroll to zoom toward the mouse. Middle-click a point to center the view on it and turn round it. Arrow keys pan. With no tool on, left-drag also rotates. Light keeps the light where you look now: turn the model and the surfaces that face away go dark, so corners, margins and undercuts show (as exocad's light from view). Click it again for the normal light. Click an axis on the small X Y Z marker to look down it; click reset to go back. Persp switches to a square-on view for judging lines. Mesh shows the triangles.

Section cuts the model open like a CAD cross-section. Arch keeps the cut square to the arch as it moves. Drag the gold ring on the plane or use the slider. From view puts the cut flat to the screen, through the middle of the view: turn the model first, then click. Cut through on a channel row cuts along the axis of that channel, and Turn turns the cut about the axis. The small window shows the outline of the cut at the nearest channel. In that window the mouse wheel zooms, a drag moves, a double click goes back, and Fit all shows everything the plane cuts.

Save session writes one file with the mesh, zones, selections, direction, trims and settings. Work is also kept in this browser, so after a crash the app offers to pick up where you left off.

Printer profiles live in this browser on this computer. They do not follow you to another computer, and clearing browsing data removes them.