Short answer: a paper yarn cone is specified by its taper, axial length (L), small-end inner diameter (d) and large-end inner diameter (D), plus paper grade, finished weight and surface finish. Our kraft paper cones are made in two taper families. The available ranges are:
| Dimension | 4°20′ taper | 5°57′ taper |
|---|---|---|
| Top (nose) inner diameter, d | 27.5–28.5 mm | 27–28.5 mm |
| Bottom (base) inner diameter, D | 57.5–58.5 mm | 67.5–68.5 mm |
| Axial length, L | 170–173 mm | 170–173 mm |
| Paper grade | 350–450 GSM | 350–450 GSM |
These are available ranges, not tolerances or batch measurements. The exact size for your order is fixed on the approved drawing or sample. The rest of this guide explains how to measure a reference cone and what to agree before ordering.
Name the dimensions before comparing cones
Use L for axial length, d for the small-end inner diameter and D for the large-end inner diameter. Inner diameter means the open bore, not the outside of the rim. Record outer diameter separately when it is part of the drawing. A phrase such as "top diameter" is incomplete unless it says whether it is inside or outside and where it is measured.
The taper is written in degrees and minutes. 4°20′ means 4 degrees 20 minutes, about 4.33°, and 5°57′ is about 5.95°. Order labels such as "4x20", "4.20" or "4 inch 20 degree" usually refer to the 4°20′ family, but decimal 4.20° is a different angle, so confirm the taper on the drawing. See 4°20′ vs 5°57′: how to choose a taper.
How to measure a reference cone
- Identify the cone, supplier lot and drawing revision. Record the date and condition of the sample.
- Use suitable measuring tools checked for the task, and support the cone so the paper is not compressed while you measure.
- Measure axial length between the end faces, not along the sloping wall.
- Measure the nose and base bores at agreed distances from the rims, and note the position with each result.
- Take readings in several orientations at the same cross-section when you are checking variation.
- Weigh finished empty cones on a suitable balance. Record paper GSM separately from cone weight: GSM is paper mass per square metre, while cone weight is the finished part.
Diameter is not the same as roundness
A single diameter reading does not describe the whole cross-section. Several readings at one cross-section show how much it varies, while a formal roundness requirement needs a measurement method both sides agree on. Keep the measurement position, sample support and instrument the same whenever you compare results. There is no universal ovality tolerance for paper cones, so write the limit you need into the order.
Check repeat lots against the approved reference
- Agree nominal length and bores, measurement depths and tolerances from the approved drawing.
- Select samples according to an agreed plan and keep lot identification.
- Record individual readings and the observed range, not only an average.
- Inspect rim damage, loose layers and storage condition alongside dimensions.
- Hold out-of-limit stock for review before it goes to the winding floor.
Vibration, unstable package build or uneven unwinding can have several causes. Check the cone, holder seating, machine condition, yarn and settings before blaming one of them, compare against the approved reference on the same setup, and change one factor at a time. Our slippage, vibration and collapse guide walks through that process.
Buyer checklist: 18 checks before you order
Technical specification and approval:
- Exact winding-machine model and holder configuration.
- Taper in degree-minute notation, taken from the approved drawing.
- Axial length and how it is measured.
- Nose inner diameter and measurement depth.
- Base inner diameter and measurement depth.
- Any required outer diameter, wall thickness and rim profile.
- Dimensional tolerances agreed in writing.
- Roundness measurement method, positions and acceptance limits.
- Paper grade and GSM, stated separately from finished cone weight.
- Finished cone weight and the weighing procedure.
- Surface finish (smooth, velvet or embossed), colour, marking and printing.
- Notch shape, position and dimensions, if your application needs one.
- Strength or other tests: method, sampling, acceptance and records.
- Mill trial plan, reference sample and the drawing revision approved for production.
Commercial and shipment:
- Quantity by specification and the confirmed MOQ.
- Carton configuration, identification, net and gross weight, dimensions and transit protection.
- Price, currency, validity, payment terms and delivery term.
- Production schedule and the invoice, packing, transport, inspection and origin documents your forwarder and broker need.
What to send with an inquiry
Send a drawing with labelled dimensions, measurement positions, tolerances and revision number. Photographs of the nose, base, side wall and holder help explain the application but cannot prove fit on their own. Include rim profile, notch detail, finish and the winding machine the cone will run on. See the paper cone specifications page and the incoming QC checklist for spinning mills.
Send your winding-machine model, reference cone or drawing, taper, finish, quantity and destination through our sample and quotation form.
Frequently asked questions
What are the dimensions of a 4°20′ paper cone?
Our 4°20′ paper cones are available with a top inner diameter of 27.5–28.5 mm, a bottom inner diameter of 57.5–58.5 mm and an axial length of 170–173 mm. The exact size is fixed on the approved drawing or sample.
What are the dimensions of a 5°57′ paper cone?
Our 5°57′ paper cones are available with a top inner diameter of 27–28.5 mm, a bottom inner diameter of 67.5–68.5 mm and an axial length of 170–173 mm. The exact size is fixed on the approved drawing or sample.
What does 4°20′ mean on a paper cone?
It is the taper angle written in degrees and minutes: 4 degrees 20 minutes, about 4.33°. It is not the same as a decimal angle of 4.20°, so confirm the taper on the drawing.
Is there a standard tolerance for paper cone dimensions?
No universal tolerance applies to every paper cone. Agree nominal dimensions, measurement positions and tolerances in writing against the approved drawing or sample before production.
