Question about integral bolsters

[Timo Nieminen]

Hmm. We could call the karakulak, flyssa, and yataghan knives rather than swords (in the same sense that the European sword-sized messer is a "knife"). Then the question is why use integral bolsters on very large knives as well as swords. Or rather, why use something different.

I think it is enough explanation for why these are constructed differently to sabres: there're built like giant knives.

How heavy do yataghans get? My only large example has a blade the length of a typical katana blade, and is all of 400g. The grip is lighter than the original, I think. Originally, it might have been as heavy as 500g! But I have a shorter one which manages 465g; it has a really thick blade.

[Emanuel]

Thank you for staying on this Timo

I disagree with you on the typology of these weapons, but that's irrelevant so I won't get into that.

On the subject of weight, I've been thinking about it. Specifically, do you need a substantial bolster as you go up in weight and length? Was the blade liable to snap at the handle?

A typical large two-handed messer was something like 1m long, and 1.8kg ( including blade and long slab hilt) and didn't have a bolster.

I haven't weighted my flyssas but the longest has a 110cm long, 1.5cm thick blade and certainly feels heavier than 1kg.

[Timo Nieminen]

I don't think you need a substantial (or integral) bolster as the weapon gets longer and heavier. Among yataghan-like weapons, the heavier ones are more likely to have an integral bolster, but I think that's because they have heavier hilts and thicker blades at the base. That is, the extra weight follows from having the integral bolster, rather than the other way around.

The meeting of tang and blade is a potential weak point, and blades do break there. A blade with an integral bolster is less likely to break there. If the integral-bolster heavy-bladed weapons are used as weapon/tools like khukuri, then it might be important for strength. If it's a "pure" weapon, less important.

[A. G. Maisey]

I'm not going to talk about ethnic knives, or historic knives, I'm going comment only on why a maker would choose to use an integral bolster rather than a bolster or guard that is pinned and soldered.

If you pin and solder you need to drill through the blade.

Holes in blades create a weak point.

A bolster forged from, or fire welded to the blade has the opposite effect:- it strengthens the blade.

Its not necessarily because knives have a habit of breaking at the junction of blade and hilt, its just that an integral bolster is superior construction to a bolster pinned and soldered.

Then there is the factor of craftsman preference. If the maker is primarily a smith, it is easier for him to make a blade with an integral bolster than it is for him to fiddle around with drill/pin/solder. If the maker is primarily a cutler, it easier for him to drill/pin/solder than to consider an integral bolster. The cutler will get a forging that he needs to turn into a knife, a flat blade without the lump that needs to be filed to shape for a bolster is easier for him to work with.

I have made many blades in damascus with integral bolsters, I made custom knives and blades for a fairly lengthy period, about 20 years from memory, and I was an early member of the Australian Knife Makers Guild. I was primarily a smith, not a cutler.

[Emanuel]

Thank you Timo and Alan for your explanations.

I am approaching the questions from a historical point of view and while I understand the advantages of forging a blade with an integral bolster, I am also trying to understand how this preference or technique spread in a certain area and time frame.

For almost four hundred years the yataghan type of blade in the Western Ottoman empire is forged flat, with a decorative bolster soldered or fixed to the base of the blade with an adhesive, not pinned. Ivory, horn, or metal scales are pinned to the tang to form the handle and a decorative strip is affixed around the edges of the handle.

At the same time, small cutlery in Italy and in Central Asia appears with a forged or welded bolster. In Western Europe this has late-medieval roots. Knives with integral bolster are also made in Istanbul in the 1700s.

Then at some point around 1800, or maybe earlier, we see instances of the yataghan type of blade with a forged bolster, in Anatolia, Kabylia, and Bulgaria. This method does not replace the older one, and is not related to blade size in the Bulgarian context, but in Anatolia appears to accompany large blades with T-section. The forged bolster is is not a technique used in other sword or sabre designs anywhere near the Ottoman empire at the time, but some earlier 17th century Tatar sabres seem to use it.

The sporadic adoption of this method of bladesmithing makes me wonder if we have a peculiar, itinerant group (possibly ethnic) moving around and spreading this bladesmithing technique and preference. If we do, then what is the direction of this movement?

The style of very long and heavy yataghan with very substantial integral bolsters seems to become popular again towards the end of the 19th century in rural Anatolia. In this context it supposedly becomes a show feature, part of costume.

Emanuel

[Emanuel]

I'll update this thread with a yataghan dated 1239/1826, with Turkish ribbon pattern welding and T-spine and integral bolster construction. This makes it the earliest example of integral bolster on such a sword I've seen, and contemporary with the earliest dated flyssa.

Originally posted in "3 large yataghan...".

[kronckew]

my karaculak yataghan,or shepherd's knife from bulgaria has an integral bolster. way back someone mentioned it might be 18c. (photo) blade is not 't' section.

structurally, the blade is like a beam, if you drill holes in it on the neutral axis which generally runs down the centre of the blade and tang, you lose very little if any structural strength. the further away from this neutral axis, the greater the compressive and tensile stress that acts on the material. on blades without integral bolsters, they usually have a sudden reduction in blade width where the blade enters the guard, if any and separate bolster, in order to fit inside the dimensions of the grip. this produces a structural incongruity and especially if the 'corner' is square, will allow progressive cracking and failure at this notch due to the high stress that a notch causes there. an integral bolster neatly avoids this.

a khukuri does not have an integral bolster, many now sport 'habaki' style bolsters to guide it into the scabbard, but khukuris are mostly differentially hardened and tempered such that the spine and tang/blade juncture are left a lot less brittle that the cutting 'sweet spot'. a bent khukuri (or sword) can be bent back into shape, a snapped one cannot easily be mended in the field.