The hammer-and-anvil stage of making a blade is, IMHO, the quickest, easiest and most enjoyable. Grinding, sharpening and polishing take much longer, in my experience, and offer far more opportunities for ruining the work beyond all hope of repair...
After shaping the steel bar or blank and forging in the bevels, adjusting curve profiles, straightening out twists & kinks &c, but before hardening/tempering, is (IMHO) the best time to do the vast majority of the cold work, when the blade is in its annealed state and soft enough to be cut with a file. I start by skimming off the super-hard 'skin' of scale, cementation &c with an angle-grinder (extremely carefully, since it's very easy indeed to wreck the blade at this stage by 'digging in' with the grinder disk if it's not held absolutely steady and straight, causing humps and hollows &c); then I file out any irregularities, and 'plane' the blade flat and true by draw-filing, at the rate of approx 1 hour per 6 inches of blade (Japanese swordsmiths use a specialised tool like a woodworkers' drawknife for this process)
If I've done the filing properly, I should now be able to get an acceptable rough finish on the belt grinder.
Then it's heat-treatment time (*the* most nerve-racking point in the whole game; is the blade going to warp on hardening, or not..? If it comes out of the quench looking like a banana, and trickling water on the convex side of the still-hot warped blade doesn't pull out the warp, there's nothing for it but to anneal, hammer out the warp and try again with the oil slightly more pre-heated, hoping this time it'll come out OK)
After hardening, the belt grinder should whisk off the baked-on oil residues, firescale &c in half an hour or so. Tempering should leave nothing but some pretty colors, best removed by hand with emory cloth (ranging from 'killer' to 'imperceptible' grit size) followed by buffing, polishing with loose grit on a rag rubber, cleanup with Autosol and fitting of hilts & furniture.
Cleaning up a blade already heat-treated presents special problems. I'd forget all about the angle-grinder, unless fitted with a paper-backed sanding disk or fine-grit flapwheel (and even then I'd worry about wrecking the hardness of the edge by overheating; see below) Your problem will be cutting the 'skin'. The kamis seem to use a grinding wheel like a bench-grinder; rather them than me. I can see where the wheel allows them to grind into the recesses of fullers &c and follow the contours of cannel-ground (curved or 'teardrop') blade sections, but unless you've had years of practice, as they have, I wouldn't risk it; a bench-grinder can screw up a nice blade in the time it takes for your concentration to slip just a tad... The belt-grinder is also of limited usefulness in this context, since most khuks don't present nice flat, straight planes; they have fullers and concave/convex sections. The roller end of the belt grinder will get into some of these nooks & crannies, but probably not all. Scythe-stones, slipstones and emory cloth will get the job done, but only at the expense of many long, tedious hours.
The tool I'd suggest, if available, is the Dremel, with a selection of flapwheels, abrasive wheels, circular stones and if possible, diamond-dust burrs (if you know a dentist or dental technician, ask nicely; they tend to use them a few times and sling them out with plenty of cut still on them for brutal work such as steel polishing) to get rid of skin, scale, hammer pocks &c. It's slow going, but a darn sight quicker than hand work.
As regards overheating, the rule of thumb is; if it's too hot to hold, it's too hot, and should be cooled off in water or (if available) a water-soluble oil such as machinists' cutting oil (what we call 'suds' over here).
If you overheat, you won't 'kill' the edge, even if you overheat so much that the blade turns straw yellow or even blue; in effect you're tempering the blade, sacrificing hardness for flexibility. An uneven temper (some soft spots in an otherwise hard edge, for example) is, however, a real pain and can cause a whole lot of problems; and one of the glories of the khukuri is its zone-hardening. It'd be a real shame to compromise that. So; go slowly, and stop & quench as soon as it gets too hot to hold.
Once you've got an evenly ground surface, start the polishing process with flapwheels and carborundum-impregnated rubber wheels/tips until you reach a roughly reflective surface, at which point there's nothing for it but to go in with wet & dry emory cloth before buffing, polishing with loose grits &c.
It's messy, dirty, uncomfortable and extremely *boring* work, and the temptation to give up as soon as you've got a finish that's close enough for jazz is very strong; but a true mirror finish is an absolute joy and invariably worth the effort.
Anybody interested in forging and finishing blades, making hilts, furniture & scabbards &c &c will get tremendous help and pleasure from Dr Jim Hrisoulas' book ' The Complete Bladesmith ' (order online from
www.paladin-press.com) which will tell you literally everything you need to know about bladesmithing, from getting started to forgewelding the finest Damascus. Dr H may have a turn-round time that makes medieval cathedral builders look swift (sorry, Rusty; still no word...) but he's one of the finest living bladesmiths and a very skilled and accomplished teacher and communicator.
