Tambour Door Slat Width & Track Radius Calculator
Calculate the exact maximum slat width that glides around your curved router track without binding, plus total slat count and canvas backing dimensions in UK Metric (mm) or US Imperial (inches).
Tight kitchen breadboxes: 40–65mm (1.5"–2.5"). Campervan tambour doors: 75–100mm (3"–4").
Calculated Tambour Cut List
Recommended Slat Width
17.9 mm
74% of max chord (smooth glide)
Absolute Max Slat Width
24.2 mm
Wider will bind in curve
Total Slats Required
30 Slats
Includes 90° bend wrap
Canvas Backing Size
576 × 529 mm
Leaves track tenons exposed
Live 90° Curved Track & Slat Chord Blueprint
Tambour Door Slat Width Reference Chart (By Track Radius)
Pre-calculated maximum and recommended slat widths for a standard 9.5mm (3/8") router track groove with 8mm (5/16") slat tenons.
| Track Center Radius | US Imperial Equivalent | Absolute Max Slat Width | Recommended Slat Width | Best Application |
|---|---|---|---|---|
| 38 mm | 1.5 inches | 20.9 mm (0.82") | 15.5 mm (5/8") | Compact Desk Breadboxes |
| 50 mm | 2.0 inches | 24.2 mm (0.95") | 18.0 mm (11/16") | Kitchen Appliance Garages |
| 65 mm | 2.5 inches | 27.8 mm (1.09") | 20.5 mm (13/16") | Media Consoles & Credenzas |
| 75 mm | 3.0 inches | 29.9 mm (1.18") | 22.0 mm (7/8") | Campervan Shower & Closet Doors |
| 100 mm | 4.0 inches | 34.7 mm (1.37") | 25.5 mm (1.0") | Large Tall Pantry Roll-Tops |
How to Calculate Tambour Slat Width & Avoid Track Binding
When a rigid wooden tambour slat enters a 90-degree curved router groove, its tenon acts as a straight geometric chord inside an annular ring bounded by the inner track wall (Rinner) and outer track wall (Router). If the slat width exceeds the maximum chord length allowed by your groove clearance, the outer corners of the tenon wedge tightly against the outer curve while the center belly drags against the inner radius.
W_recommended = 0.74 × W_max (Provides 26% dynamic cornering margin)
Step-by-Step Workshop Procedure for Routing Tambour Tracks
- Machine Slat Tenons First: Mill a rabbet or tongue on both ends of your slats so the tenon thickness is 1.0mm to 1.5mm narrower than your spiral upcut router bit diameter.
- Route Mirror-Image Side Panels: Clamp an MDF corner radius template to both cabinet side panels and rout the track in 3mm depth passes using a template guide bushing.
- Leave Canvas Margin at Track Ends: Cut your cotton duck canvas backing 24mm (1 inch) narrower than the overall slat length so bare wood tenons ride inside the waxed groove without fabric fraying.
Frequently Asked Questions (Tambour Door Calculator)
How wide should tambour door slats be for a 50mm (2 inch) radius track?
For a 50mm (2 inch) centerline track radius routed with a 9.5mm (3/8 inch) groove and 8mm slat tenons, the absolute maximum slat width before geometric binding is 24.2mm (0.95 inches), and the recommended smooth-gliding slat width is 18mm (0.70 inches).
How much clearance should a tambour door track groove have?
Route your curved tambour track 1.0mm to 1.5mm (1/32 inch to 1/16 inch) wider than the thickness of the wooden slat tenon. For example, pair an 8mm tenon with a 9.5mm (3/8 inch) spiral router bit.
What is the best backing material and glue for wooden tambour doors?
10 oz to 12 oz tightly woven cotton duck canvas bonded with brush-on contact cement or heat-activated PVA veneer adhesive provides flexible hinge support without stretching over time.
Why does my tambour door bind and jam in the 90-degree corner?
Tambour binding occurs when the rigid flat slat chord is too wide for the inner and outer walls of the curved router groove, or when glue squeezes between individual slats during canvas lamination.
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