What is the main difference between E71T-11 and E71T-GS?

The S in E71T-GS limits that classification to single-pass welds, while the G usability designator leaves important operating characteristics to the manufacturer. E71T-11 is a defined usability type, but each product can still have specific pass, thickness, diameter, position, and approval limits.

Can E71T-GS replace E71T-11?

Not automatically. Compare the exact product data sheets, machine manual, WPS, base metal, joint, position, pass count, mechanical-property requirements, approvals, and inspection criteria. A matching tensile-strength digit does not make the wires interchangeable.

Does GS mean gasless flux-core wire?

Do not use GS as proof that a wire is gasless or that it needs a particular polarity. Confirm shielding and polarity on the exact product label and current manufacturer data sheet; the Forney E71T-GS product reviewed here is self-shielded and DCEN, but that product documentation controls the setup.

E71T-11 vs. E71T-GS: Flux-core wire guide

The practical answer to E71T-11 vs. E71T-GS is not simply “thick steel versus sheet metal.” E71T-GS is single-pass only, while E71T-11 may permit more than one pass only within the exact product and procedure limits. Neither label, by itself, approves a wire for your weld.

Use the classification to narrow the search. Then verify the manufacturer, product, shielding, polarity, diameter, operating range, mechanical properties, approvals, lot, storage, welding procedure specification (WPS), and inspection requirements before loading the spool.

E71T-11 vs. E71T-GS at a glance

Decision point	E71T-11	E71T-GS
What the suffix establishes	A defined AWS usability classification	G usability details are manufacturer-dependent; S means single-pass only
Multiple passes	Only when the exact product literature and WPS permit them	No; select a different approved wire if the joint needs multiple passes
Shielding and polarity	Check the exact product sheet	Check the exact product sheet; “GS” does not prove the setup
Mechanical data	Classification requirements apply, but product values and job requirements still matter	Do not infer unspecified properties from “71” or another brand’s E71T-GS sheet
Best selection rule	Match the documented product to the joint and procedure	Use only for a documented single-pass application within the product limits

If you have not yet decided between FCAW and GMAW, first compare flux-cored wire vs. solid wire. This page assumes FCAW is already an acceptable process for the job.

Decode the flux-cored wire classification

The current AWS A5.20/A5.20M:2025 specification covers carbon-steel FCAW electrodes used with or without shielding gas. Its classification requirements address weld-metal chemistry, mechanical properties, usability, sizes, identification, manufacturing, and packaging. Optional designators can add requirements such as lower-temperature toughness and diffusible-hydrogen limits.

Read the common part of each label this way:

E identifies an electrode.
7 places the deposited weld metal in the 70 ksi tensile-strength class under the specified classification test.
1 indicates all-position capability at the classification level. A particular diameter or product can still have tighter position limits.
T identifies a tubular, flux-cored electrode.
-11 identifies a defined usability type. It is not permission to ignore the product’s pass, thickness, or approval limits.
-GS uses a general usability designator, with S restricting the electrode to a single-pass weld. Do not expand “GS” into a universal claim about gas, polarity, or application.

The 70 ksi class is not a finished-weld guarantee. Joint design, base metal, heat input, technique, defects, and inspection all affect performance. A suffix also does not prove code acceptance or prequalification.

What exact manufacturer documents show

These two current or available product records demonstrate why classification is only the first gate. The values belong to the named product and must not be transferred to another spool.

Field	Hobart Fabshield 21B	Forney item 42300
Classification	AWS A5.20 E71T-11	E71T-GS
Shielding and polarity	Self-shielded; DCEN	Self-shielded; DCEN
Pass and position limits	Data sheet lists flat, horizontal, vertical-up, and overhead; light structural applications under 3/4 inch. Confirm pass limits in the WPS and current product guidance	All position; manufacturer says it is best suited to single-pass applications
Published mechanical properties	Typical: 91 ksi tensile, 62 ksi yield, 22% elongation; Charpy V-notch listed as not applicable	Product page lists 79 ksi tensile; yield, elongation, and impact values are not stated there
Diameter and operating data	.030, .035, .045, 1/16, and 5/64 inch. For .030: 25-125 A, 14-16 V, 55-225 ipm. For .035: 55-120 A, 17-20 V, 75-160 ipm	Item 42300 is .030 inch; the public product page does not state an operating window
Conformances and approvals shown	AWS A5.20/A5.20M, ASME SFA 5.20, ABS, and CWB	No project approval or code conformance is stated on the product page
Storage information	Keep dry, enclosed, and in original intact packaging; re-drying is not recommended	Forney SDS: keep in the original closed package in a cool, dry place and avoid extreme temperatures and incompatible materials

“Not stated” is not permission to assume. It is a prompt to obtain the current technical data sheet, certificate of conformance, lot documentation, and written application guidance—or reject the candidate when the job requires those records.

Wire-label and WPS compatibility worksheet

Complete this record for each exact spool, not for a generic E71T label. Mark non-applicable fields as N/A and identify who authorized that decision.

Record	Exact product or job requirement
Manufacturer, product, part number	____________________
AWS classification and specification edition	____________________
Package size, diameter, and lot/heat number	____________________
Data-sheet and SDS revision/date	____________________
Self- or gas-shielded; permitted gas	____________________
Polarity and power-source requirements	____________________
Single/multiple-pass and deposit limits	____________________
Permitted positions, joint types, and base metals	____________________
Tensile, yield, elongation, impact, and hydrogen requirements	____________________
Voltage, amperage/WFS, CTWD, preheat, and interpass limits	____________________
Code, owner, ABS/CWB/other approvals required	____________________
Storage, exposure, reconditioning, and discard rules	____________________
WPS number/revision and welder qualification	____________________
Inspection method, acceptance criteria, and inspector	____________________

For procedure-controlled work, compare the completed record with the WPS variable ranges—not just the trade name. The guide to WPS, PQR, and welder qualification records explains which document instructs production welding and which records support qualification.

How to choose without guessing

Define the weld. Record base-metal grade and coating, thickness, joint, position, pass count, service, governing code, and acceptance criteria.
Reject classification conflicts. Do not choose E71T-GS for a multi-pass joint. Do not assume an E71T-11 product permits the planned buildup, thickness, or position.
Check the exact product. Match shielding, polarity, diameter, operating range, mechanical properties, approvals, and storage status. Preserve the label and lot identity.
Check equipment and procedure. The power source, feeder, gun, drive roll, liner, tip, output, and duty cycle must overlap the documented range. Use the flux-core polarity guide rather than a gasless-wire shortcut.
Verify and inspect. Make a representative coupon only when the WPS or responsible authority allows it. Record the settings and apply the required visual or nondestructive inspection; bead appearance alone cannot qualify a critical weld.

If both candidates pass these gates, choose by the approved procedure and documented application—not price, spool color, or a generic flux-core wire types chart.

Safety and failure-critical boundaries

This comparison is based on published documents, not hands-on product testing. Welding creates fume, arc radiation, hot metal, sparks, noise, and electrical hazards regardless of classification.

Fume and coatings: Read the wire SDS and identify the base metal, paint, plating, oil, and galvanizing. Keep your head out of the plume and use local exhaust or adequate general ventilation. Outdoor work does not guarantee safe exposure.
Fire: Remove or protect combustibles, check hidden and opposite-side spaces, keep suitable extinguishing equipment ready, and follow the required hot-work permit and fire-watch procedure.
Electrical and PPE: Follow the machine manual before changing polarity or feed components. Use suitable eye, face, hand, body, foot, hearing, and respiratory protection for the assessed hazards.
Critical welds: Structural, vehicle, pressure, lifting, fall-protection, and other failure-critical work require the governing code, approved WPS, qualified personnel, traceable consumables, responsible welding authority, and specified inspection. This article does not approve a weld.

Use the weld-defect troubleshooting guide to identify discontinuities, but do not repair or add passes beyond the documented procedure.

Next step: verify classification, then diameter

Photograph the spool label, save the current data sheet and SDS, and complete the worksheet before setup. If the product and WPS are compatible, use the .030 vs. .035 flux-core wire guide to check the feeder path, output window, joint, and operator constraints.

The decisive question is not “Which suffix is better?” It is which exact, traceable product satisfies every requirement for this weld. If the documentation is incomplete or contradictory, stop and obtain written direction from the manufacturer or responsible welding authority.

Sources and scope

Manufacturer literature, standards, approvals, and regulations can change. Use the documents, adopted editions, and jurisdiction that apply to the work in front of you.