How much weld fills a beveled edge
Before you weld a thick butt joint you bevel the edges into a V so the weld can reach the root. The size of that groove sets how much filler metal the joint swallows — and that drives wire, time and cost. This calculator turns the prep dimensions into a groove cross-section, a weld-metal volume, and a weight, so you can order wire and quote the joint.
The geometry
For a single-V groove the cross-section is the root gap times the thickness, plus the triangular bevel on each side: area = (root gap x thickness) + (thickness – root face) squared x tan(half the included angle). Multiply by joint length for volume, add a reinforcement and loss allowance, then multiply by material density for weight.
Why the prep numbers matter
A wider included angle or a smaller root face opens the groove and adds filler fast — the bevel term grows with the square of the depth. Tightening the angle to the smallest that still gives access is the cheapest joint that still fuses to the root.
Related welding tools
Feed the weld-metal weight into the welding wire calculator to size the spool, and the welding cost calculator to price the joint. For cut prep time, see the cutting time calculator.
Worked example
A 1/2 in plate with a 60 degree included angle, 1/16 in root face, 1/16 in gap, over 12 in, plus 10 percent: the groove is about 0.142 sq in, roughly 1.87 cu in of weld metal, about 0.53 lb of steel filler.
FAQ
Single-V or double-V?
This models a single-V. A double-V on the same thickness uses roughly half the filler because each bevel is shallower, at the cost of welding both sides — prep one side at half the depth and double it if you want a quick double-V estimate.
Does it include the root pass and cap?
The reinforcement and loss percent covers the cap crown and spatter or grinding losses. Raise it for out-of-position work where more metal is lost.