Hollow/Flat/etc. grind?

[hillbilly WA]

Hi guys
I was just wondering, whats the difference between a hollow grind and flat grind and other grinds? Also, is a Scandi a grind? Coz i've been looking around at knives and these are some of the things that they have written about them, just wondering what they were.
Thanks all,
Carl

[gundy]

Edited:

Carl, here are some of Jdees (Rustic Forge) explanations. Saves me a lot of typing!

The Flat Grind (FG) is completely flat, going from the spine to the edge and is probably the most common and its main advantage is that even if badly ground it can be rectified without the skill and machinery needed for the HG. The FG makes the best slicer when the geometry is correct (a perfect example would be the Spyderco Calypso Jr whilst not a hunter it would be one of the best Commercial slicing blades available) and is probably the easiest of all grinds to sharpen œ it can be sharpened down to a single edge, can be convex ground or triple ground. It does not take as much skill to sharpen and all the work can be done on coarse and fine stones with a bit of time and patience. Because the bevels are flat, there is sufficient metal backing the edge, so it‘s much

The Convex Grind (CG) also called the Moran grind and arcs down in a convex curve down to the edge and this means the edge can be very sharp, because there‘s no secondary bevels to create the edge, just two intersecting arcs and is probably the most controversial grind œ you either like them or don‘t. Traditionally the CG has been used on large camp knives, more often than not with the true —appleseed“ shape, but more and more small blades are appearing with convex edges and flat sides. If you are unsure what a CG is have a look at a good axe œ most axes have a convex grind. The advantage of the CG is that there is no apparent secondary edge as there is on the HG and FG with the blade tapering to a single sharp edge. The disadvantage of the CG is in the sharpening as you grind it completely different to the other grinds and this makes it harder for the less experienced.

The Sabre/Scandinavian Grind (SG) is a strong edge grind. The bevel starts around the middle of the blade and proceeds flatly towards the edge and is probably one of the less popular grinds mainly due to the badly made knives in the commercial market with the exception of the Scandinavian blades, many of which do not feature a secondary edge. These knives were often disregarded due to their utilitarian shape and no guards. But, one cannot disregard history as the Scandinavians and the Sámi (Lapps) have been using such knives for hunting for centuries. I had a Roselli Carpenter for years which was a good knife and kept its edge long after many of my other commercial blades lost theirs.

[Stewart Townsend]

Some other links,

http://laventrix.net/showpost.php?p=13320&postcount=18

http://laventrix.net/showpost.php?p=13321&postcount=19

All the grinds have good points. But the heat treatment and the thickness of the steel has to be taken into the eqaution as well.

[Steven J]

Over the last 6 months I have been playing with the scandi grind. You can see the shape of the Scandi grind below. It is flat ground with no secondary bevel. This has its pros and cons.

If you are after a knife for whittling and carving you can't go past a better grind. The edge can get a little fragile for hard substances and I would not use a grind as steep as shown as the grind for cutting up an animal because you would likely damage the edge on bone. The plus side is that even when the edge has lost its razor sharpness you can still cut with ease.

For a tougher edge I would use a convex edge scandi grind. It does not really appear to have much of a convex, but the convex is formed as you sharpen using wet and dry paper on a soft surface like a mouse mat or some hard leather.

I got into playing with these types of knives as I explore my Swedish heritage and will probably not go back to another grind for the types of things I do.

Below is a photo of my scandi carving knife with the sheath I made for it, some end grain slices on a 5/16 cedar shaft, and the resulting end grain showing no tear out. These types of cuts indicate a pretty useful edge geometry, however there will be a different shape required for other purposes.

Not bad for a $15 knife.

Steve