Welder's term for proper fusion at bead edges and at starts and stops. Good tie-in means the toes blend smoothly into the base metal or adjacent bead with no undercut or overlap, and a restart melts fully into the crater of the previous rod. On pipe it also names the spot where two halves of a root meet, which is ground and feathered so the bead fuses through.
Your tie-in at the top is cold, grind the start back to a feather and make it again.
Also heard as
- tie in
- tie-ins
- tying in
Related terms
Feather
To grind the start, stop or tack of a weld to a thin taper so the next bead can tie in smoothly.
Cold lap
Shop term for weld metal that rolls over onto the base metal or a previous bead without fusing to it.
Lack of fusion
Weld metal that failed to fuse with the base metal or a previous pass at some boundary.
Puddle
Shop word for the weld pool, the molten metal under the arc that the welder watches and steers.