CaveForge

I would remove it if it would allow me but it won't.

Here is an interesting video.

The easiest most forgiving steel i know of is aisi-1080 / 1084 and it can be air quenched . The cold steel bushman knife is made with this steel, so you can look that up on youtube if you want to see how it reacts. http://www.knivesby....ating-1084.html You could also try one of the lower 10 series steel such as 1040 or 1045. You won't get a high hardness but it will be easy to sharpen.

You can clean the knife blank and stick it in a mason jar filled with boiling vinegar. A patena will form and the fractures and uneven heat sections will come out. Works well for small thiner knives, but not so much on larger & thicker blades. It will save you time and resources before you heat treat or start forming the blade.

It's not 100% decernable as to what you will get out of used either sawmill circular or band saw blades. You do not know if the blade got jambed in one spot and got hot which will make that spot brittle. Sometimes you will have a blank heat treated and a fracture will develope that you could not detect before. In my experience circular sawmill blades are generaly good so long as there were not overheated. Sawmill band saw blades have about 30% of the used blade that is still usable for knives and will heat treat well enough. Otherwise you have to forge weld that steel to ensure that there are no stress fractures and even structure. I tend to heat treat scrap steel a little less intensely and use thicker than normal quenching oil. Also saw blade steels such as M2 and M4 (most common for those applications) are rust magnets. It is fairly easy to get about 56-58RCH and have the blade with some flexability.

It would take more than one 6" RR spike to make a conventional size Ghurka Khukuri. You might be able to get away with a 6" blade Khukuri with a single spike, however it might be a little on the thin side if you are looking for authenticity. An automotive leaf spring would be a better choice in alloy. If you have the skill and the equipment to do it, i would heat up two spikes and twist them together in the Norse fasion then hammer.

Higher HP would be better and 240vAC and if possible a three phase converter (speed control) if you are working thick steel. You could look at Polar bear forge's "grinder in a box" as a good alternative. I have a Bee metal brand grinder and a radius master grinder. Some of the wiltons have the 120vAC with a step up transformer. I can't see much wrong with single phase 1hp except the work load efficiency rate. More HP means you can do a tougher task for longer before the grinder no longer has enough power to turn the wheel properly. In the case of stock removal yes more HP gives you more control as well.

Local suspension repair shops are probably the best. Just about all they have is 5160 in used leaf srpings in the scrap bins, and yes it is a chore and dangerous to cut already tempered steel as when it gets hot it graps the cutting wheel and can rip it out of your hands, not to mention all the rust and pitting removal as well as looking for fractures in the metal. I think most of my common utility knife sales come from this stock, it is more work than new stock if you intened to forge & fold the scrap steel , you might also need a way to add carbon to the folding. If you have a plasma cutter all the better it works great on cutting leaf springs just remember to leave at least 1/4" spacing around your blank tracing. Try to get the best pieces out of the scrap bin. The wider and slightly thinner transport leaf springs are generally of better quality steel. Thicker leaf springs are fine for folding but too much trouble for a straightened piece as a knife blade. I've picked up 4,6,and 8" wide leaf springs and thicknesses upto almost 1/2" . When removing the rust with an angle grinder you first grind off the top rust orangish colour rust then rince with water. Then angle the grinder a little more to get the carbon like black pitting deposits. No need to get rid of all the pitting, standard cutting and belt sanding will take care of the small stuff. Wash off between grindings, let dry then coat the metal with 2 stroke engine mixing oil and let sit for a few hours. Clean and start either flatening the steel or what ever process you want to try. Safe Journey.