Originally Posted by
handlewanker
Hi in2steam, as I read it he wanted two square or rectanguler blocks coplanar and parallel to each other, and the same size.
Being classed as a rectangle or cube gives it flat sides parallel and square to each other.
It didn't say that one surface was going to be fitted to another existing possibly not quite flat surface.
So in that case the first rectangular piece would have to be made truly flat on one face, and the other faces made parallel and square to it, with the second item identical.
Unless you have a reference certified flat surface to grind/file/scrape to, you can end up with a banana that is still coplanar.
The definition of a flat surface is a circle of infinite radius, which by it's very description can never be truly flat.
The fact that the ends are equal distant from the same point means that they will meet eventually.
Hi Mac, the scraper I made is exactly the same as the top photo, and as has been said, it's very important to remove the teeth by grinding, but BEFORE heating and forging, otherwise the end will develop hairline fractures across the edge from the teeth.
The other important bit is to thin the edge down when forging to not more than 2.5mm or 3/32" thick, otherwise you'll be wearing a groove in the stone trying to get the edge sharp.
I sharpen the scraper by holding it vertical to the stone and inclined about 1 degree to the side, left hand holding the handle at the top and the right hand holding the blade between thumb and forefinger near the bottom, giving it a forward and back motion, and rotating the point 180 degrees every few strokes, to give two distinct curved flats on the end.
For those that are new to scraping, the blade should be held at a very shallow angle to the work.
There is a tendency for some to raise the handle end to get it to cut when the edge dulls, but this just makes resharpening a longer job.
The scraper is assumed to be sharp when it will raise a scraping when applied to the thumb nail.
Last but not least, you must have complete and utter freedom from outside disturbances, so that concentration and interpretation can be applied.
If you scrape a .001" hollow at any point on the surface, then the WHOLE of the rest of the surface has to be removed to bring it flat.
Ian.