By the EVST Engineering Team · Last updated: June 30, 2026

Choosing a 6-axis robotic arm comes down to three numbers and one decision: payload, reach, repeatability, and the arm type that fits the task. Size payload by adding the part weight and the end-of-arm tool, then add 20 to 30 percent margin. Size reach to cover the full working envelope. Confirm the arm type is right before comparing brands. If you are sourcing the arm from China, verify certifications, in-country support, and whether the supplier delivers a full cell or only the bare arm. EVST supplies 6-axis industrial arms from compact 6 kg models up to the heavy 210 kg class, with four-axis palletizers reaching the 800 kg class, and ships to 100+ countries.

Why Payload, Reach, and Type Come First

Every later decision, gripper, controller, mounting, safety, and cell layout, follows from payload, reach, and arm type. Get these wrong and no tuning recovers the cell: an undersized arm cannot lift the part with margin, a short-reach arm cannot cover the envelope, and the wrong arm type makes the whole task awkward. This guide fixes all three before you request a quotation, then covers what to check when the arm is sourced from China.

A 6-axis robotic arm, also called a six-axis or articulated robot, has six rotational joints. Those six degrees of freedom let the tool reach a point from almost any approach angle, which is why 6-axis arms dominate welding, assembly, machine tending, material handling, and palletizing. The flexibility is the reason to choose one, and also the reason payload and reach trade against each other within a single mechanical platform.

Step 1: Size the Payload

The payload calculation is simple arithmetic, but it is where most undersizing mistakes happen because buyers forget the tool.

Payload required = part weight + gripper or tool weight + any cabling or sensor mass at the flange

Then add a dynamic margin. An arm accelerating and decelerating a load needs headroom above the static mass, and 20 to 30 percent is a safe default. A 4 kg part on a 2 kg gripper is a 6 kg static load, which points to a 10 kg arm once margin is included, not a 6 kg arm.

One detail buyers miss: rated payload depends on the load’s center of gravity offset from the flange. A long or offset tool reduces usable payload below the headline number, so always check the payload-versus-center-of-gravity chart for the specific model rather than trusting the single rated figure.

Step 2: Size the Reach

Reach, the arm’s maximum armspan from the base, must cover every point the tool needs to touch, plus approach and retract clearance. The practical method:

1. Lay out the task footprint: pick points, place points, machine doors, fixtures, weld seams.
2. Find the farthest two points the arm must reach from a single mounting position.
3. Confirm the arm can reach both without hitting a joint limit or singularity, which usually means leaving margin inside the nominal reach radius.
4. If the footprint exceeds any single arm’s reach, consider a longer-reach model, a different mounting, or adding a linear track to extend the working range.

The common reach failure is not the headline radius. It is wrist orientation near the edge of the envelope: the arm can position the tool at the far point but cannot achieve the required approach angle there. Validate reach with the actual tool orientation, not just the point.

Step 3: Confirm the Arm Type

Before locking in a 6-axis arm, confirm it is the right type for the motion. The main types of robotic arms differ in their degrees of freedom and the work they suit:

If the task needs free tool orientation, multi-plane motion, or welding and assembly angles, the 6-axis articulated arm is the right type. For high-speed planar pick-place choose a SCARA, for light high-speed sorting a delta, and for tasks beside people a collaborative robot. The rest of this guide assumes a 6-axis arm is the right fit.

Step 4: Match to a 6-Axis Model

EVST’s QJAR 6-axis range gives clear payload-and-reach anchors. The table below maps common task profiles to a model class. Full datasheets, including repeatability and payload-versus-reach curves, are available on request.

Beyond these handling models, EVST also builds dedicated welding variants (H suffix, such as the QJR6-2000H at 6 kg and roughly 2,014 mm reach) and painting variants (P suffix, such as the QJRP6-2700P at 6 kg and roughly 2,701 mm reach), plus four-axis palletizers that extend to the 800 kg class. Browse the full lineup on the EVST 6-axis robot overview. For a refresher on how the joints and links of an articulated arm fit together, see the EVST industry guide to robotic arm structure and anatomy.

Step 5: Sourcing a Robotic Arm from China — What to Check

Many buyers source 6-axis arms from China for the price-to-payload ratio, then discover the real cost is in integration and support, not the arm. If you are sourcing from China, verify these points before you commit:

• Certifications — confirm CE for the target market, and IATF 16949 if the parts feed an automotive supply chain. Third-party marks such as SGS and TUV indicate the production line is audited, not self-declared.
• In-country support — an arm with no local commissioning, spare parts, or service is a risk. Ask how the supplier handles installation, training, and warranty in your country.
• Full cell vs bare arm — a robot arm alone is not a working cell. Confirm whether the supplier delivers grippers, vision, fixtures, safety, and integration, or only the body, which leaves the integration cost and risk on you.
• Documentation and standards — English datasheets, electrical drawings, and a controller that meets recognized safety standards prevent surprises during acceptance.
• Lead time and spares — confirm production lead time and spare-parts availability up front; a low arm price loses its value if a controller board takes months to replace.

EVST addresses these directly: IATF 16949 automotive-grade certification, CE / SGS / TUV third-party marks across the range, a field-engineering network across 100+ export countries, and full-cell delivery rather than body-only supply. The company also holds a granted invention patent (CN ZL 2020 1 1601091.6).

RFQ Checklist: What to Send for a Quotation

A request-for-quote with the items below returns a real configuration and number quickly. Without them, the supplier has to ask a round of follow-up questions and the quote slips.

• Part weight, dimensions, and material
• Gripper or tool already chosen, or a description of the grip surface
• Task description (welding, assembly, palletizing, handling, machine tending, finishing)
• Cycle time target
• Work envelope footprint and the farthest reach points
• Required repeatability or accuracy
• Production volume (parts per shift, shifts per day)
• Mounting preference and available floor space, plus whether a linear track is needed
• Required certifications (CE, IATF 16949, customer-specific)
• Installation country and any hazardous-area requirement (which may require an explosion-proof model)

To request a quotation, contact EVST sales via the contact page or email [email protected]. With a complete package, a first technical reply with a recommended model and configuration typically lands within 48 hours.

Why Buyers Specify EVST 6-Axis Robots

EVST, headquartered in Chengdu, has delivered 600+ automation projects and ships to 100+ countries over seven years of operation. For 6-axis arm buyers specifically:

• Payload anchors from compact 6 kg arms to the heavy 210 kg class in six-axis, with four-axis palletizers to the 800 kg class, from one product family
• Dedicated welding and painting arm variants alongside general handling models
• IATF 16949 automotive-grade certification, plus CE, SGS, and TUV third-party certifications across the range
• A 100+ country field-engineering network for on-site commissioning and operator training
• Full-stack supply: 6-axis arms alongside collaborative robots, SCARA, delta, positioners, and linear tracks, reducing multi-vendor interface risk
• In-house process capability, including teach-free intelligent welding (3D vision seam finding and SLAM mobile welding) and force-controlled assembly (20 to 50 N class)

Frequently Asked Questions

How do I choose the payload for a 6-axis robotic arm?

Add the part weight, the gripper or tool weight, and any cabling or sensor mass at the flange, then add 20 to 30 percent dynamic margin. A 4 kg part on a 2 kg gripper is a 6 kg static load, which points to a 10 kg arm after margin. Also check the payload-versus-center-of-gravity chart, because an offset tool reduces usable payload below the headline number.

What payload and reach range do EVST 6-axis arms cover?

EVST QJAR 6-axis handling arms range from the 6 kg QJR6S-1 at 751 mm reach up to the 210 kg QJRB210-1 at 2,688 mm reach, with 6 kg long-reach models such as the QJR6-3 at 2,001 mm and 50 kg models such as the QJR50-1 at 2,012 mm. Dedicated welding and painting variants and four-axis palletizers to the 800 kg class are also available.

What are the main types of robotic arms?

The main types are 6-axis articulated arms for flexible welding, assembly, and handling; SCARA arms for high-speed planar pick-and-place; delta or parallel arms for very high-speed sorting of light parts; and collaborative robots for tasks shared with operators. Choose 6-axis when the task needs free tool orientation or multi-plane motion.

What should I check when sourcing a robotic arm from China?

Verify certifications (CE for your market, IATF 16949 for automotive, plus third-party SGS or TUV marks), in-country commissioning and spare-parts support, whether the supplier delivers a full cell or only the bare arm, English documentation and recognized controller safety standards, and confirmed lead time. A low arm price loses value if integration, support, or spares are missing.

How long is the lead time and quotation turnaround?

With a complete RFQ package, EVST typically returns a first technical reply with a recommended model and configuration within 48 hours. Standard 6-axis arms ship on lead times confirmed at quotation; custom end-effector and integration scope extends the timeline and is quoted separately.

About the author: The EVST Engineering Team supports buyers and integrators specifying 6-axis robot cells across welding, assembly, machine tending, handling, and palletizing. EVST (EVS TECH CO., LTD), headquartered in Chengdu, has delivered 600+ automation projects and ships to 100+ countries over seven years of operation, with IATF 16949 automotive-grade certification and CE / SGS / TUV third-party certifications across the QJAR, collaborative robot, SCARA, and delta product families.