Andrew Gillespie

I continued experiments with boric acid out of curiosity. I am now convinced that it cannot work for steel as it becomes too corrosive at the temperatures needed for steel. Rather leave it for the jewellers working with precious metals and lower temperatures.

Somebody did mention dust and the possibility of it burning. Yes, metal can burn. They are known as class D fires and are very difficult to extinguish. In the very unlikely event of you accidentally creating thermite there is no chance of extinguishing that fire, just get yourself to safety. Where I work we have aluminium dust and it has ignited and I dumped a CO2 extinguisher on it and it only burnt hotter. I knew putting water on it would cause an explosion, but the CO2 making it worse was a surprise. We now have a Class D extinguisher that works by surrounding the burning material with a so

I steam them and then grate cheese over them or make cheese sauce. Apparantly a small percentage of people have a gene the makes some chemical in sprouts and other veggies taste like bitter soap.

I managed to get hold of an anti-scale Consursal Z1100 which is a german product. Works well, but is very expensive.

I have found that brands of cobalt bits are not all equal. Alpen is the best I have used so far.

I am quarantined at home because I got that flu that's going around. I just did a heat treat of a 1075 blade and used an anti-decarb (Condursal Z1100) for the first time. I think it worked. But a file doesn't skate. I accidentally over heated the oil. Could that cause it to not harden properly?

Thanks, all. I will use 1075.

I can easily get 1075, 1085 and 1095, but I don't know enough to choose between them. Which one is best for a beginner doing only stock removal. I want to make simple fixed blade knives.

The quenching is temp 815°C for 1075, right?

If it were me curiousity would beat wanting to save it and I would cut through the oddity diagonally and then polish the edge as finely as possible to see how deep it goes.

Thanks all, I am starting to understand better. What was confusing me was the large grain size which was my mistake by letting it cool in the kiln.

I need to get a better understanding as I use an electric kiln for heat treating. I am not sure what it looks like. I cleaned it (1075 steel) thoroughly with acetone and put 2 coats of titanium dioxide containing white paint on. I heated to 885C for normalizing and cooled slowly in the kiln. The paint did not live up to the no-peel promise. I have sanded the flat part of the blade, but I am not sure if I am seeing is decarb or something else.

I read that carbon will damage the heating elements in an electric kiln. Is that true?

I wish I could buy the commercial anti-scale, but I can't find anyone who sells it. My attempt at using boric acid was not 100% but it helped a little. I'm wondering if I applied it unevenly causing one side to cool at a slower rate.

I didn't put it down, I hung it with a wire hook through a hole drilled into the handle section. I will try the straightening hot, hopefully I will get it right.