Disk-linisher proving not flat enough.
What else can I try?
Never got 4inch disks working as air-powered 4inch angle grinder has metric fine thread whereas linishing disk nut has metric coarse. However, with 5inch angle grinder, linishing disk has equal(?) chance and result is "dips" off-centre - including in corner where weld is. So no chance to finish with emery wrapped around a file - cannot get cloth-backed emery to most important location. Also finding that with very flat finish, can scribe continuation of plate surface with Stanley knife across etched surface, so can capture in photo and measure directly the fillet leg-length, throat and penetration.
Belt-linisher like FabCo's often - but not always - have is useful - can finish by draw-file, two stages of emery-cloth around file then macro-etch with iodine etchant.
Thinking what I could have which is portable which would serve same purpose of belt-linisher...???