Revo High Flow nozzles: when an upgrade is useful

What high flow actually means

Volumetric flow expresses the volume of filament extruded per second. E3D explains that maximum flow depends on line width, layer height, temperature and extrusion force, among other factors. Its Revo High Flow nozzle aims to raise flow in a compatible Revo setup. To assess an upgrade, first compare the flow requested by your profile with a limit actually verified on your configuration. A print defect alone does not measure that limit.

According to the E3D product page, Revo High Flow nozzles use a custom internal geometry that increases the surface area for thermal transfer to the filament. E3D also states that, unlike its earlier Volcano and SuperVolcano hotends, these nozzles keep exactly the same form factor as standard Revo hotends, so you do not need to change your mount or fan duct. The page lists a maximum temperature of 300°C and a 1.75 mm filament diameter.

That framing matters for your expectations. The upgrade addresses the melt zone, not the whole machine. If your extruder, motion system or slicer profile cannot use the extra flow, you will not see the benefit. Our guide to 3D printer nozzles covers the nozzle's own role in that chain.

Why top speed is the wrong number to chase

Speed in millimeters per second and flow in cubic millimeters per second describe different quantities. Check whether a machine's advertised figure concerns travel, printing speed or a particular test condition. It does not by itself establish the melting capacity of your hotend, nozzle and filament combination. The Revo High Flow page itself notes that time savings depend on the part and profile, not a flow figure alone.

The useful reasoning starts from volumetric flow and converts it to speed based on the line cross-section. A wider line or a taller layer consumes more plastic per millimeter traveled, so at the same flow rate the real speed drops. This is exactly what E3D's documentation describes when it explains that line width, layer height, print temperature and extrusion force all affect the maximum achievable flow.

Before replacing a hotend, record the slicer's volumetric limit and where it actually reduces speed in the project. Compare that limit with a test for your material and profile, without treating under-extrusion as sole proof of insufficient flow. This identifies the problem you expect a new nozzle to address; it does not guarantee a post-purchase print duration.

How E3D measures flow, and what that means for you

E3D publishes a support page dedicated to volumetric flow rates for its Revo nozzles. The company states up front that a hotend's maximum flow cannot be accurately expressed as a single value, and that its figures are a reasonable estimate validated by its in-house engineering team and subject to updates. It also notes that your own printer setup and filament choice will affect the flow you actually reach.

The method is documented. According to E3D, all values were obtained with a 60 W Revo HeaterCore, a Hemera XS extruder, the same motion system, and a single-wall vase-mode test object with one bottom layer. Layer height was set to 50% of the nozzle diameter and line width to 125% of it, which gives 0.2 mm and 0.5 mm for a 0.4 mm nozzle. Part cooling was at 100%, and the materials were Prusament Jet Black in PLA, ASA and PETG, dried for at least one hour at 60°C in a vacuum oven.

These are internal measurements in one specific configuration. They guarantee nothing for a different extruder, heater or machine. E3D itself says that not all extruders can achieve the same flow as the Hemera XS, so if yours delivers less force, expect a lower ceiling.

Material and temperature set the first ceiling

A high-flow hotend does not change polymer physics. E3D notes that viscosity falls as temperature rises, which helps flow, but its tests stayed within the normal printing range of each material. Exceeding recommended temperatures reduces the polymer's structural properties and, according to the same documentation, can potentially produce toxic fumes. This does not authorize exceeding the filament's temperature range to raise flow.

Compare results by material and nozzle diameter, as E3D's documentation does. It gives neither a universal value transferable to any filament nor a ranking of every polymer. For a buying decision, record the test filament, its preparation, temperature and nozzle geometry. A PLA figure does not predict the gain for another formulation simply because it belongs to the same family.

Our guide to print temperatures lists the usual ranges by material family. Stay within the filament maker's range, then adjust the profile instead of pushing temperature to squeeze out more flow.

Nozzle size, layer height and line width: the profile levers

According to E3D, increasing nozzle diameter reduces how much the filament cross-section has to change, which lowers the required extrusion force and raises the maximum volumetric flow. That is why the Revo High Flow page highlights the addition of 1.00, 1.20 and 1.40 mm nozzles alongside the existing 0.4, 0.6 and 0.8 mm sizes. That relationship does not establish that another nozzle size suits your part's detail or profile: check both before selecting it.

Layer height works the other way. E3D explains that a thinner layer increases shear load, which raises the back pressure the extruder has to overcome. Line width also increases that load, but the company found that at the same volumetric flow, prints with a wider line performed better, because under-extrusion shows up more on thin walls.

Evaluate these settings together. A 0.4 mm nozzle or fine layers alone do not predict the benefit: inspect the flow requested at the programmed speeds and your setup's verified limit. Our layer height guide helps examine that setting alongside nozzle diameter, without replacing a flow test or your model's detail requirements.

When the upgrade is useful, and when it is not

E3D answers the print-time question directly on its product page. The company says time reduction depends on many variables, including the part itself. With its premade slicer profiles it expects a decrease in most cases, but warns that very small, detailed models with little or no infill may not show a dramatic improvement, because those profiles prioritize visual quality on the outer perimeters.

One scenario to examine is a part whose slicer reduces speed to honor an already verified flow limit, using a compatible setup and suitable extruder. Compare the profiles and their estimates, then check the result on a test part. Conversely, E3D's small detailed-model example concerns its premade profiles; it does not guarantee small savings for every miniature or thin part regardless of profile.

Check compatibility last. The E3D page lists the compatible products: Revo Micro, Revo Six, Revo Voron, Revo CR, Revo Hemera XS, Revo Prusa MK3, Revo Prusa Mini, Revo MicroSwiss NG and Revo Biqu H2 V2. Outside that list, Revo High Flow nozzles are not stated to be compatible. To decide between a partial swap and a full assembly, read complete hotend assembly vs individual parts, and place the expense in context with the budget tool.

Sources and limits

• E3D Revo® High Flow Nozzles
• Revo Support: Volumetric Flow Rates – E3D American Express Apple Pay Diners Club Discover Google Pay Maestro Mastercard PayPal Shop Pay Union Pay Visa

We organize manufacturer and community documentation; we have not measured these products ourselves. The manual for your exact model takes precedence over general guidance.