As a sword afficionado I have learned that a hollow ground blade is authentic, visually appealing, and expensive. I get that it is cool, but what is the real advantage. In a sword designed to cleave a mail clad limb, isn't a hollow ground edge more delicate that a flat almost chisel edge?

What is the advantage of the hollow ground edge in a medeival battle? Is it more durable, easier to maintain? sharper?

The actual makers are going to give you a better more thorough answer, but...
I don't consider the hollow ground versus diamond shape to necessarily have a whole lot to do with the outer 0.060" of cutting edge that is normally where the minor nicks and dings occur on an edge. The more significant aspect of their differences is in the sections of the blade that are half way between the spine and the cutting edges.

The hollow ground sword can have a thick spine with less weight than a flat diamond profile with the same thickness spine. The basic thickness of the spine gives the sword most of its rigidity in thrust and bending in the plane of the flat of the blade. In a way, it is sort of like using a steel I beam instead of a solid rectangle shaped bar of steel when building a structure. For strength in bending, the I beam is just much more efficient for its weight.

Tony, I don't know if youv'e seen or touced an Albion hollow ground blade but on their swords the curve of the hollow ground does not terminate at the edge but a few millimeteres back from the edge forming a reinforced edge geometry. If you run you finger across the width of the blade it slopes down from the central ridge then up again ever so slightly where the reinforcment occurs then back down to the final edge. This geometry is very subtle but allows for a much stronger edge.

I have heard this called a secondary bevel before but I was corrected on this by someone, so I do not know what the correct term for this is. The accuracy and consistency of the hollow ground and this edge reinforcement that Albion produce is quite amazing and absolutely flawless on the sword that I own.

As a neophite bladesmith, I'll toss my $0.02 worth in. Just about any blade design is a compromise in the elements that make it up, whether it be a knife or a sword. A hollow ground sword blade, which I understand, is thicker than the hollow grind that you will find on a knife blade. From the way I consider it, it does three things. First, it leaves a thick, relatively speaking, central rib that will make the blade slightly more rigid to support the point for thrusting through resistant material. Second, it removes metal from the lateral portions of the blade to reduce the weight of the blade. Thirdly, it decreases the angle from the center of the blade to the edge and forms a narrower wedge to facilitate cutting. The blade will have to be thick enough just behind the edge to support a flat or slightly convex secondary bevel that would be thicker than what one would find on a knife to withstand the force of blow delivered to a resistant target. Remember, that in fuction, a sword is more like an axe than a knife. From what I picked up from from Reinhart's DVD, "The Myth of the Sword" (pardon me if I got his name wrong but I can't find the DVD right now) narrowing the primary bevel on the blade may make it less able to deal with something like mail but more able to cut flesh and bone. It would also reduce it's ability to punch through armour by decreasing the rigidity. Other more learned people may well disagree, but that's my take on it.

First of all i should probably check that when people have referred to a "hollow ground" sword they mean a fuller right? i haven't encountered the term hollow ground blade before however in the context of diamond section swords i'm guessing that is what people are referring to.
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My impression was that lighter swords were common in mailled periods such as the viking and early medieval periods certainly most of the authentic examples of early period swords have large single fullers (quickly googled) sort of like the type X from http://www.oakeshott.org/Typo.html
and that the diamond section became more prominent when plate armour appeared due to it's ability to use the extra weight of the blade to bend the plates inwards or cleave them apart (no easy task, but easier with a diamond sect. than a fullered i think.)

although to use a fullered sword's speed to find the holes and gaps between plates makes sense, from what i know most early plate armour had mail under the plates covering any openings between them, this only really disappears when advances in plate armour allow the plates to interlock to the extent that there basically are no gaps.

One can save weight using one or more fullers on a blade but if one also wants a narrower blade using hollow grinding or a thick central ridge works better.

If you look at the Oakshott sword by Albion it has a fuller but the primary bevels are also hollow ground while retaining thickness next to the edge: http://www.myArmoury.com/talk/viewtopic.php?t...mp;start=0

The Brescia Spadona has a short fuller and subtlely hollow ground bevels, I believe, with reinforced edges:
http://www.albion-swords.com/swords/johnsson/...rescia.htm
http://www.myArmoury.com/review_alb_brescia.html

Hollow grinding can be deep and very obvious or barely perceivable: If a blade is very narrow deep hollow grinding can be almost " fuller like " if the blade stock is very thick. Lots of variables that can tune a sword's crossection for relative effectiveness in thrust and cutting.

In part the design decision of using fullers or hollow grinding on a diamond section blade is an aesthetic decision and in part a functional decision as I mentioned at the top.

Malcolm, for hollow ground look at Albion's Regent, Kingmaker or Burgundian.

Ah, I see where the confusion is Malcom. Hollow grinding and fullered are two different things. Hollow ground is basically a diamond cross section that has has the four faces ground inwards towards the centre, making the faces hallow.

Here's a convienent image from myArmoury's own features section.

Keep in mind the image of the hollow ground blade profile above does not show the geometry of the edge reinforcement present in some swords.

my apologies. thank you for the explanation Corey, i live and learn.