Vehicle
Push-toy cars, vans, jeeps and buses at any scale, with wheels that really roll.
Fit test coupon generator Free
Cut it once per material and know your clearances before cutting a whole project.
Open Fit test coupon in the app
Free, no sign-up. Runs in your browser.
In short: Calibration piece: slots with stepped clearances plus a key. Cut it first for every new material to find the right kerf and slot clearance.
Every laser and every sheet is a little different: the beam removes a strip of material (the kerf), and "3 mm" plywood is rarely exactly 3 mm. Copying someone else's numbers is how joints end up loose or split.
The fit test is a small calibration coupon: a comb of slots with stepped clearances and a key that slides into them, plus a strip of holes in stepped sizes for your axle or pin rod. Cut it in the material and at the settings you will use for the real project, try the key in each slot and the rod in each hole, and note which one fits the way you want: snug for a press fit, free for a part that turns.
Enter those numbers in any generator's material settings (kerf, slot clearance, press-fit and running-fit offsets) and the whole design uses them. Cut a new coupon when you change material, lens or settings.
The guide Kerf and clearance explains the difference between the two and how to read the coupon.
Settings
All of these can be changed in the app, and the 3D preview updates as you type. The name under each setting
is its key in a share link, e.g. https://laserpuzzle.app/app/#/fit-test?first=…; a link only
needs the settings that differ from the defaults.
Coupon
| Setting | Default | What it does |
|---|---|---|
First clearancefirst | -0.15 mm | From -1 to 1 mm. |
Clearance stepstep | 0.05 mm | From 0.01 to 0.5 mm. |
Number of slotscount | 7 | From 2 to 20. |
Slot depthslot_depth | 10 mm | From 3 to 50 mm. |
Hole strip
| Setting | Default | What it does |
|---|---|---|
Rod diameterrod_diameter | 3 mm | Measured diameter of your rod (axle, dowel). Adds a strip of test holes; 0 = no hole strip. From 0 to 30 mm. |
First hole offsethole_first | -0.2 mm | Hole diameter = rod diameter + offset. From -1 to 1 mm. |
Hole offset stephole_step | 0.05 mm | From 0.01 to 0.5 mm. |
Number of holeshole_count | 11 | From 2 to 25. |
Plus the material and machine settings every generator has: material thickness, kerf, slot clearance, sheet width, sheet height, part spacing, engrave part labels, cut line colour, engrave line colour.
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