Weld Symbol Builder

Build a correct welding symbol and drop it on your drawing. Choose the weld type, side, size, length or intermittent pitch, contour, weld-all-round, site weld and process tail, see it drawn against a schematic joint in the ISO 2553 or AWS A2.4 convention, read a plain-English statement of what the symbol requires, and export it as DXF at true scale or as SVG.

What it gives you

• Fillet, square, V, bevel, U, J, plug or slot, spot, seam and surfacing
• Arrow side, other side or both, with the ISO identification line or the AWS above/below layout
• Size prefixes a, z, s, d and c; continuous, single length or n × l (e) intermittent, staggered
• Contour, weld all round, site weld, backing run, ISO 4063 process number and tail note
• Plain-language readout of the specification, DXF with real arcs and dashed identification line

Method and standards

ISO 2553 System A places the symbol on the continuous reference line for the arrow side and on the dashed identification line for the other side; symmetrical welds omit the dashed line. AWS A2.4 and ISO System B put arrow-side symbols below the reference line and other-side symbols above. The builder follows those rules and the standards' proportions, and the readout tells you what the symbol demands so it can be checked before issue.

How to use it

1. Pick the convention and the weld type.
2. Set placement, size, length and any supplementary symbols.
3. Check the readout, then download DXF or SVG.

Questions engineers ask

Which convention should I use in the UK?

ISO 2553 System A is the norm for UK and European drawings. Use the AWS layout for North American clients or where the drawing states AWS A2.4.

What is the difference between a and z on a fillet?

a is the design throat thickness; z is the leg length. For an equal-leg fillet z is roughly 1.41 times a.

Is the DXF at drawing scale?

It is at 1:1 with the text height you choose, typically 3.5 mm, so it inserts at the right size on a 1:1 drawing sheet.