Why Paper Cone Specifications Matter
Paper cone specifications are not a formality — they are the engineering baseline that determines whether a cone runs cleanly on your machine or stops it. A taper angle 1.6 degrees wrong will not seat on the spindle cradle. A nose inner diameter 1mm outside the acceptable range creates vibration at high RPM. A cone weight 4g below specification indicates a thinner wall and reduced burst strength — a cone that may hold for one shift and fail mid-production on the third.
The cost difference between a specification-compliant cone and a non-conforming one is rarely more than a few cents per piece. The production cost of discovering the non-conformance on the winding head — not at goods-in — is a multiple of that margin across every affected doff cycle.
This page covers all key parameters for paper yarn cones. For a full side-by-side comparison of both taper angle specifications, jump to the comparison table, or view our cone range directly.
Taper Angle: 4°20′ and 5°57′
The taper angle is the first parameter to establish — and the one that cannot be compensated for by any other adjustment. It determines how the cone seats on the spindle cradle, the geometry of the yarn helix during winding, and whether the finished package releases cleanly after doffing. Two angles cover the full range of modern spinning mill applications.
5°57′ — High-Speed Autoconer Standard
The 5°57′ taper is the industry standard for high-speed automatic winding machines. It is the correct specification for:
- Schlafhorst Autoconer X5 and X6
- Murata QPRO and Process Coner
- Savio Orion, Polar, and Espero
The wider taper creates a secure lock on the spindle cradle at winding speeds up to 2,000 m/min and above. The winding geometry of these machines is calibrated for 5°57′ — yarn traverse angle and cone surface angle are matched for even layer-by-layer package build. Using a 4°20′ cone on a 5°57′ cradle produces a loose fit and generates vibration that damages package geometry and accelerates bearing wear.
4°20′ — TFO, Doubling, and Select Autoconers
The 4°20′ taper is used on two-for-one (TFO) twisters, ring doubling machines, and certain autoconer configurations where the spindle geometry requires the shallower angle. TFO machines in particular require the 4°20′ specification because the yarn feeds off the cone through a balloon around the spindle — the narrower taper seats more snugly under the centrifugal forces of twisting. A 5°57′ cone on a TFO spindle would sit loosely, producing uneven balloon tension and package instability.
Always confirm the required angle in your machine manufacturer's technical manual before placing an order. The correct taper angle is listed under the spindle assembly or bobbin specification section. For a full machine-by-machine compatibility reference, see our 4°20′ vs 5°57′ taper angle guide.
Dimensional Specifications
Three dimensional parameters define a paper cone's physical interface with the machine: height, nose inner diameter (the small end), and base inner diameter (the large end). Both taper angle specifications share the same standard height. The inner diameters differ because a shallower taper over the same height produces a narrower base.
Dimensional accuracy matters at two levels: individual cone compliance with specification, and consistency across consecutive production batches. A cone that passes incoming inspection but is at the limit of the acceptable range on nose diameter will behave differently on the spindle cradle from one in the centre of that range — particularly at high RPM where small geometry variations amplify into vibration and package ovality.
4°20′ vs 5°57′ — Specification Comparison
| Parameter | 4°20′ Cone | 5°57′ Cone |
|---|---|---|
| Taper angle | 4°20′ | 5°57′ |
| Height | 170–173mm | 170–173mm |
| Nose inner diameter (top) | 27.5–28.5mm | 27–28.5mm |
| Base inner diameter (bottom) | 57.5–58.5mm | 67.5–68.5mm |
| Paper grade | 350–450 GSM kraft | 350–450 GSM kraft |
| Cone weight | 40–42g | 40–42g |
| Surface finish | Smooth, velvet, or embossed | Smooth, velvet, or embossed |
| Primary machine type | TFO twisters, doubling machines, select autoconers | Schlafhorst X5/X6, Murata QPRO, Savio Orion/Polar/Espero |
| Production method | Fully automatic | Fully automatic |
All dimensions are for Aziz Packaging Limited production. A batch quality certificate showing measured dimensional values is issued with every shipment. View full product specifications →
Paper Grade: 350–450 GSM Kraft
Kraft paper grade — measured in grams per square metre (GSM) — determines wall thickness, burst strength, and moisture resistance. The standard range for auto-machine paper cones is 350–450 GSM. Both the 4°20′ and 5°57′ specifications use the same GSM range; the grade within that range is selected based on application.
Higher GSM within the range produces a thicker wall with greater burst strength — the cone can withstand higher yarn tension without collapsing mid-package. It also provides better moisture resistance, which matters for cones stored in humid warehouse conditions or used on production floors with significant seasonal humidity variation.
For standard ring-spun cotton winding at moderate speeds, cones toward the lower portion of the range are adequate. For compact-spun cotton, synthetic yarn, or any application above 1,600 m/min, specifying toward the upper end of the range reduces the risk of cone collapse under sustained tension load at speed.
When requesting a proforma invoice, specify the application rather than a GSM figure if you are uncertain — advise your yarn count, fibre type, and winding speed and we will confirm the appropriate grade. For a detailed breakdown of how GSM affects winding performance, see our paper cone weight and GSM guide.
Cone Weight: 40–42g
Standard auto-machine paper cones weigh 40–42g per piece. Cone weight is a direct indicator of material content — a cone at 38g has a thinner wall than a 42g cone of the same dimensions, regardless of what the supplier's specification sheet states. For this reason, incoming inspection should include measured cone weight from a production batch sample, not only dimensional checks.
Cone weight is also a practical factor in two commercial calculations. First, doff weight: the total weight of a finished yarn package is cone weight plus yarn weight — a 2g difference per cone becomes meaningful when calculating net yarn yield per package for invoicing or inventory purposes. Second, packing density: heavier cones per carton adds gross weight per container, which affects freight cost when pricing on a weight basis.
On our batch quality certificates, the measured average cone weight from the production run is recorded alongside dimensional measurements. If you require a specific weight within the 40–42g range for your application, advise this when requesting a proforma.
Surface Finish: Smooth, Velvet, or Embossed
Surface finish is the friction interface between the cone body and the first yarn layers during winding. When a new cone loads and winding begins, the first few layers either grip the cone surface or slip — and that outcome is determined almost entirely by the combination of yarn type and surface finish. The wrong finish is not a minor quality issue: smooth finish on polyester yarn causes first-layer slippage on every cone loaded across every winding head on every doff cycle.
For ring-spun cotton Ne 20s–50s, wool, and linen at standard winding speeds. Natural fibre surface irregularities provide adequate grip against smooth kraft paper.
For polyester, nylon, acrylic, polypropylene, compact-spun cotton of any count, ring-spun cotton above Ne 60s, and any yarn wound above 1,600 m/min. Also suitable for cotton where a single cone specification across all yarn types is preferred.
For high-twist ply yarns and worsted constructions with high liveness that tend to spring back during early-layer winding. Not typically required for standard autoconer applications.
Both smooth and velvet finish are available as standard within a single order — specify per line item on the proforma invoice if your production runs both yarn types. For the full selection guide with a yarn-type decision table, see our velvet vs smooth vs embossed surface finish guide.
Frequently Asked Questions
What taper angle do I need — 4°20′ or 5°57′?
The taper angle is determined by your machine, not your yarn type. For high-speed autoconers — Schlafhorst X5 and X6, Murata QPRO, Savio Orion, Polar, and Espero — the correct angle is 5°57′. For two-for-one (TFO) twisters and ring doubling machines, the correct angle is 4°20′. Check your machine manufacturer's technical manual under the spindle or bobbin specification section to confirm. The two angles are not interchangeable — a cone with the wrong taper will not seat correctly on the spindle cradle.
What is the difference in dimensions between a 4°20′ and a 5°57′ cone?
Both share the same standard height (170–173mm) and a similar nose inner diameter. The key difference is at the base: the 5°57′ cone has a base inner diameter of 67.5–68.5mm, while the 4°20′ cone has a base inner diameter of 57.5–58.5mm — approximately 10mm narrower. This reflects the difference in taper angle applied across the same length. The two cones are dimensionally incompatible with each other's spindle cradle geometry.
What GSM should I specify for high-speed winding?
For winding above 1,600 m/min, compact-spun cotton, or high-tension synthetic yarn, specify toward the upper end of the 350–450 GSM range. Higher GSM produces a thicker wall and greater burst strength, reducing the risk of cone collapse under sustained tension. For standard cotton winding at moderate speeds, cones in the lower portion of the range are adequate. Advise your yarn type and winding speed when requesting a proforma and we will confirm the appropriate grade.
Can I order a mix of 4°20′ and 5°57′ cones in the same shipment?
Yes. Both taper angle specifications can be included within the same container shipment, with each specification and quantity declared separately on the commercial invoice and packing list. You can also split by surface finish — for example, smooth and velvet finish within the same order. Specify each combination as a separate line item when requesting the proforma invoice.