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Cardboard or plastic core? The calculation for your case
Cardboard or plastic for your caseTell me the environment, reuses and pressure: I’ll put cardboard and plastic in the ring and tell you which costs less per use, with the wall each one needs.
Your full report is ready. Where shall I send it?
I’ll show you walls, weights per metre and cost per use of cardboard and plastic for your case right here, and email you a copy. One email only, no automatic sign-up.
ROLL Lab estimate, not a test certificate. Prepare your enquiry for the manufacturer →
How the calculation works
The calculator works in four steps:
- Required pressure: from the strength entered by the user or estimated from the roll, multiplied by a safety factor.
- Cardboard wall: thick-walled tube formula, with an equivalent cardboard strength reduced according to the humidity of the environment (dry, humid, wet). The reduction follows published sensitivities per point of moisture.
- Plastic wall: the larger of the crushing check (Lamé) and the buckling check, with a long-term factor for creep and a temperature factor. See the wall calculator.
- Cost per use: the price of each core follows its mass (cross-section × density) against a same-size reference; plastic divides its cost by the declared reuses, plus the cost of returns.
The verdict names the material with the lower cost per use and flags cases where cardboard is not recommended regardless of cost (wet environment, fibre-free area). Cycle figures from Fiaptech technical documentation (a company with corporate ties to ROLL) are used as minimum values: above them the calculator invites you to measure your real cycles, rather than changing the verdict.
Limits: indicative prices expressed as ratios; creep and temperature modelled with simplified factors; the cost of failures is not considered. ROLL Lab estimate, to be confirmed by a test on the real core.
Frequently asked questions
Why is the comparison not at equal size?
Because cardboard and plastic do not have the same strength for the same wall, especially in humidity and over time. The right comparison is between cores that carry the same roll.
Does the calculator take humidity into account?
Yes: it reduces cardboard strength according to the chosen environment. In a wet environment cardboard is not recommended even if the cost calculation favoured it.
What about plastic creep?
It is included with a long-term factor on stiffness and allowable stress, plus a temperature factor. These are prudent ROLL Lab assumptions, to be calibrated with tests.
Sources
- Fiaptech technical documentation, Smart Book “Which core?” (a company with corporate ties to ROLL)
- EN 13476-2 and EN ISO 9967 (creep)
- Published core industry studies on the moisture–strength relationship of cardboard
- ROLL Lab analysis
Other apps in the lab
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Weight per metre and per piece of a PVC, PP, HDPE, PS or ABS core, compared with cardboard.
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base🇪🇺PPWR: is your core ready for 2030?
Material, post-consumer recycled share and type of contact: PPWR 2030 and 2040 targets and the gap to close.
prof🔁Does reuse pay?
Plastic and cardboard core prices, return rate and return cost: break-even threshold, average trips and cost per use.
prof🧱Minimum plastic core wall
From film and roll to the pressure on the core, then to the minimum wall by material and temperature, with creep and buckling.
prof🚚Cores per pallet, truck and container
How many cores per pallet, per articulated trailer and per container, with the volume and weight limit.