FEFCO & ECMA Corrugated Flute Caliper, Bend Allowance & Slot Relief Engineering Guide
Parametric Formulas & Dimensional Allowances
Accommodates both the folded dust flap caliper (T) and the inner rollover wall caliper (T) plus 0.5mm folding clearance.
Prevents adjacent top and bottom flaps from binding against each other when folded 90 degrees.
Converts internal usable product cavity dimensions into external shipping parcel dimensions.
Standard Material & Tooling Tolerance Table
| Board / Flute Grade | Flutes per Meter | Nominal Caliper (T) | Rollover Bridge (2T+0.5) | Slot Relief (2T) | Primary Packaging Use Case |
|---|---|---|---|---|---|
| 300–350 gsm SBS / Ivory Board | Solid Paperboard | 0.40 – 0.45 mm | 1.35 mm | 1.5 mm Cut | Cosmetic cartons, pharma boxes, playing card decks |
| 400–450 gsm Kraft / FBB Board | Solid Paperboard | 0.50 – 0.60 mm | 1.60 mm | 1.5 mm Cut | Bakery gable boxes, retail blister header cards, cup sleeves |
| F-Flute Micro-Corrugated | 410 – 425 / m | 0.80 mm | 2.10 mm | 2.0 mm | Luxury litho-laminated retail packaging, electronics boxes |
| E-Flute Corrugated (32 ECT) | 290 – 305 / m | 1.50 – 1.60 mm | 3.50 mm | 4.0 mm | FEFCO 0427 e-commerce mailers, subscription boxes, pizza boxes |
| B-Flute Corrugated (32 ECT) | 150 – 165 / m | 2.80 – 3.00 mm | 6.50 mm | 6.0 mm | FEFCO 0201 shipping cartons, canned goods, retail case packs |
| C-Flute Corrugated (32–44 ECT) | 125 – 135 / m | 3.80 – 4.00 mm | 8.50 mm | 8.0 mm | Master warehouse shipping cartons up to 22 kg |
| BC-Flute Double-Wall | Combined B + C | 6.50 – 7.00 mm | 13.50 mm | 13.0 mm | Heavy industrial machinery crates and pallet export boxes |
Generate Custom 1:1 .DXF, .SVG & .PDF Files Using This Standard
FEFCO 0427 Mailer Box
Generate custom 1:1 FEFCO 0427 roll-end tuck-top e-commerce mailer box dielines with automatic E-flute/B-flute bending allowances, 3D fold preview, and free DXF/SVG/PDF export.
Tuck End Folding Carton
Create custom 1:1 ECMA Reverse & Straight Tuck End folding carton dielines for cosmetics, pharmaceuticals, and retail boxes. Automatic glue flap & dust flap math.
Coffee Cup Sleeve Dieline
Generate mathematically exact curved conical coffee cup sleeve dielines for 8oz, 12oz, 16oz, and custom tapered cups. Real frustum cone radial unfolding math.
Pillow Box Dieline
Generate custom 1:1 pillow box dieline templates with mathematically matched circular crease arcs for jewelry, gift cards, wedding favors, and apparel.
ECMA Gable Top Handle Box
Generate custom 1:1 ECMA Gable Top handle carrier box dielines in .DXF, .SVG, and .PDF with die-cut carry handle slots, gusset roof creases, and interlocking base flaps.
FEFCO 0201 RSC Shipping Carton
Generate 1:1 FEFCO 0201 Regular Slotted Container (RSC) corrugated shipping box dielines in .DXF, .SVG, and .PDF with automatic slot width, flap length, and manufacturer glue joint.
PDQ Retail Counter Display Tray
Generate 1:1 retail POS countertop PDQ display trays and shelf-ready packaging dielines in .DXF, .SVG, and .PDF with sloped side wings, low front lip, and tall header backboard.
Snap-Lock 1-2-3 Bottom Box
Generate custom 1:1 ECMA A60.20 / FEFCO 0216 Snap-Lock (1-2-3 bottom) folding carton dielines for heavy bottles, candles, and mugs. Free DXF, SVG & PDF export.
Tray & Sleeve Drawer Box
Generate 1:1 two-piece sliding drawer tray and outer wrap sleeve packaging dielines on a single sheet with automatic slide-fit clearance (+1.5T). Free DXF, SVG, PDF.
Bottle Carrier Basket
Generate custom 1:1 4-pack and 6-pack beverage bottle carrier basket dielines with integrated ergonomic top handle and cell dividers. Free DXF, SVG & PDF.
Paper Shopping Bag Dieline
Generate custom 1:1 gusseted retail paper shopping bag dielines with top turnover cuff, 4 rope-handle punch eyelets, and block-bottom diamond folds. Free SVG, DXF, PDF.
Lid & Base Gift Box (0320)
Generate custom 1:1 two-piece telescopic lid and base gift box dielines (FEFCO 0320) for jewelry, board games, iPhones, and luxury rigid boxes. Free DXF, SVG, PDF.
Rigid Book Mailer Envelope
Generate custom 1:1 rigid cardboard book mailer and variable-capacity e-commerce envelope folder dielines with perforated zipper tear-strip opening. Free DXF, SVG, PDF.
Ready-to-Cut Product Presets (Packaging Dielines)
63.5 mm x 88.9 mm x 17.5 mm (2.5" x 3.5" Standard 54-Card Poker Deck on 310gsm Casino Stock)
33.0 mm Diameter x 104.5 mm Height (Standard 30ml / 1 oz Euro Glass Dropper Bottle with Rubber Pipette)
52.0 mm x 32.0 mm x 114.0 mm (Standard 50ml Crimp-Neck Spray Flacon with Overcap)
152.4 mm x 101.6 mm x 50.8 mm (6" x 4" x 2" USPS First-Class / Royal Mail Small Parcel Tier)
Fits all universal 90mm rim paper cups (10oz, 12oz, 16oz, 20oz) with 82mm upper grip and 70mm lower grip diameter
85 mm x 27 mm x 58 mm (Standard 4.5 oz / 130g Cold-Process Artisan Soap Loaf Slice)
Shop-Floor Troubleshooting & Engineering FAQs
Should packaging dielines be drawn from the inside (printed side) or outside?
Standard CAD dielines on CadFold are projected flat with the inside / die-face up so steel-rule die makers and digital cutting tables crease from the correct side without mirroring asymmetric glue flaps.
How does grain / flute direction affect box stacking strength?
Corrugated flutes should always run vertically (parallel to the box Height H) on shipping cartons (FEFCO 0201) to maximize top-to-bottom Edge Crush Test (ECT) stacking strength. On FEFCO 0427 mailers, running flutes parallel to the front-to-back Width (W) prevents the wide hinged lid from bowing.
Why do my physical laser-cut cardboard prototypes feel tighter than die-cut production boxes?
A physical steel creasing rule embosses a U-shaped channel into the board, whereas a laser score line vaporizes surface fibers without compressing the flute medium. When laser-prototyping corrugated board, add +0.5mm to your T setting.
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