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In SCA rapier, a Junior Scientist is someone who uses their academic or technical knowledge to test various questions about things like armor strength or blade behavior ''without'' the benefit of an actual laboratory. Typically their experiments are done in the living room or garage, using available materials.
In SCA rapier, a Junior Scientist is someone who uses their academic or technical knowledge to test various questions about things like armor strength or blade behavior ''without'' the benefit of an actual laboratory. Typically their experiments are done in the living room or garage, using available materials.


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Here are reports on some of their work:
Here are reports on some of their work:


(Editor's Note: I have reorganized the content to group broken links together and the text of sub-pages here to keep the topic together.)
----
----
[[The Machine]]
* [[The Machine]] (Broken link)
* [[Combat Anatomy]] or "If that was a real blade, what would it have done to you?" (Broken link)
* [[Schlager Penetration Tests]] By Don Robin of Gilwell (Broken Link)
* [http://www.iceweasel.org/ek_schlager_test.html East Kingdom Armor Punch Tests] by Don Dylan ap Maelgwn and Don Thomas de Castellan
* [http://www.iceweasel.org/ek_schlager_mask_test.html Destroying Masks] By Fergus MacRae, and a team of Junior Scientists from the East Kingdom.
[ftp://ftp.cirr.com/pub/SCRIBE/Armory/Blades.Txt Historic blade weights and balance points] Comparing measurements of a number of historic weapons. (Broken Link)
* [[A Treatise Concerning Leg Wounds]] By Don Aubrey de Baudricort and Joachim van der Haus
<BR>
==Testing Lighter Armour==
by Tivar Moondragon
 
===Introduction===
This is a description of tests I made in April of AS XXXVI (2001) as part of a discussion with Don Giovanni, when he was Deputy Society Marshal for Rapier. The Kingdom of Ealdormere had asked for permission to experiment with using lighter armor in conjunction with their heavier blades.
====History====
The standard body armor for SCA rapier has been four ounce leather, four layers of Trigger cloth or the equivalent, ever since rapier was first officially allowed by the Board of Directors back in AS XIV (1979.) That standard has been pretty well shown to withstand broken foil blades and most broken epees. (Problems can arise when an epee breaks with a jagged, rather than a flat point; the only two serious broken blade injuries in over thirty years of SCA rapier fighting have been from jaggedly broken epees.)
 
When schlager blades were introduced to the SCA, Junior Scientists in the East Kingdom tested them and determined that four ounce leather or four layers of Trigger cloth would also stand up to an untipped or broken schlager blade, thus, the standard continued as it was.
 
Over the years, however, questions would occasionally arise about the necessity of this "penetration resistant" armor against blades that tended to break less frequently that either foils or epees. The Ealdormere experiment was the culmination of those questions.
 
My concern, when I heard about this experiment, was that doing preliminary testing of a new type of body armor by taking it on the field for full-speed combat was not a good idea. The only way to find out that the armor didn't work would be through a catastrophic failure--the armor, and quite probably its wearer being penetrated--sort of like the Calvin and Hobbes method of finding out the load rating on a bridge.
 
So I decided to dust off my Junior Scientist hat, and do some tests under more controlled circumstances.
 
===The Tests===
One of the things the East Kingdom's Junior Scientists had found was that an untipped schlager blade actually penetrated fabric more easily than a broken one. Presumably this is due to the fact that the tip has a smaller cross section than a broken blade. I decided that rather than break any of my blades, I'd just remove their tips and test them that way.
 
====Testing an untipped heavy blade against SCA rapier armor, wet rawhide and various combinations of rawhide and cloth:====
 
I tried samples of 4 layers of Trigger and 4-ounce leather on The Machine, hitting it with full-force blows, trying to penetrate. I used my schlager; AEthelyan's schlager (the one affectionately known as "Rebar," which is way too stiff for combat, and spends its time over the mantelpiece) my Mark I Del Tin and my daughter Rosalind's Mark II Del Tin. All of these blades have the tips cut flat and the corners rounded just enough so that there's not a point there. "Rebar" has a tip profile of 3.5 x 10 mm, which is pretty large (the other schlager is 3.5 x 6 mm, my Del Tin is 2 x 7 mm and Rosalind's is 3 x 7 mm.)
 
On multiple hits, the best I managed was a few small holes in the top layer of the Trigger, (it looked like one corner of the blade had started to penetrate, but it was nowhere near enough for a downcheck if I was testing armor) and one pinpoint-sized hole in the leather. These hits were registering at 8 lbs and up, many maxed out beyond the scale's 18-lb limit.
 
Against plain wet rawhide (simulating bare skin) I managed to penetrate about half the time; those penetrations were all at 2 lbs. The other shots just skidded across the rawhide. I figure a similar shot would leave a nasty scrape on bare skin and probably a friction burn on skin covered with cloth.
 
Against the rawhide with a single layer of Trigger, I penetrated about 1/3 of the time. Those penetrations were in the 7-9 lb range.
 
Against the rawhide with a single layer of linen, I got one penetration at 12 lbs before I decided that the rawhide was too full of holes to continue (I kept getting false penetrations, where the fabric got pushed through an existing hole.)
 
====Drop tests====
I then decided to test in the opposite direction. I took the lead weight from my old drop-tester and mounted it on the various blades (sans hilts) that I was using, and dropped them down the tube from my drop tester onto fabric samples clamped over a piece of 4" pipe. Because of the slightly greater weight of the blades compared to the rest of the drop-tester, this gives an impact slightly higher than the 4 joules of a standard armor test, but it still has the advantage of consistency and minimum variables.
 
I tested Trigger, Judy Linen and some medium-weight cotton fabric. Each test consisted of dropping the weighted blade from a height of 30 centimeters onto the fabric sample three times and observing the results.
 
====Four Layers====
* Four layers of Trigger passed against all four blades. (Twelve drops, zero penetrations.)
* Four layers of linen passed against all four blades, although my schlager and Rosalind's Mark II Del Tin penetrated the first layer. (Twelve drops, zero full penetrations, two with top layer damage--which still passes the SCA drop test.)
* Four layers of the cotton passed most of the tests. AEthelyan's "rebar" schlager damaged the first two layers of the fabric and my Del Tin penetrated completely on two of the three tests. (Twelve drops, two full penetrations, two penetrations of the top two layers--which qualifies as failing the SCA drop test.)
 
====Three Layers====
* Three layers of Trigger withstood my schlager, was penetrated once by "rebar" and twice by each of the Del Tins. (Twelve drops, five full penetrations.)
* Three layers of linen were penetrated twice by my schlager, had the top layer penetrated by "rebar", were penetrated twice by my Del Tin and once by Rosalind's Del Tin. (Twelve drops, five full penetrations.)
* Three layers of the cotton was penetrated on all three tests by my schlager, "rebar" and my Del Tin, and on two of the tests with Rosalind's Del Tin. (Twelve drops, eleven penetrations.)
 
I didn't see much need to test one or two layers.
 
===Conclusions===
The "four layers of Trigger or equivalent" standard seems sufficient protection against a schlager or Del Tin that has lost its tip. This implies that it's sufficient protection against a broken blade as well, due to the larger cross-section involved, but I'd be interested to try this experiment with a broken Del Tin (considering that the only broken Del Tin I've seen had a sharp spur at one corner of the break.)
Removing a single layer of fabric produces a significant increase in the likelihood of penetration (about 40%.) The threshold point for penetration seems to lie between three and for layers of Trigger. (This has been confirmed by independent tests done by Don Robin of Gilwell.)
Combining the drop-test results with the Machine results, I think it's pretty clear that a single layer of Trigger, linen or other lightweight cloth will not reliably prevent penetration by an untipped blade. There was an injury in the Barony of the Stargate (Houston) in December of AS XXXIV (2000) which bears this out. A fighter was hit in the hand with a Del Tin that had lost its tip. The blade punched through his light leather glove, and penetrated about two inches into his hand.
I think it's doubtful that two layers of fabric would be sufficient either. Three layers might be sufficient, but if "lighter" armor means it’s only reduced by a single layer, what's the point?
 
==The Touch-kill Question==
Why "If you feel it, call it." isn't necessarily correct...<BR>
By Tivar Moondragon
 
There is a belief in some SCA kingdoms that rapier fighters should call any blow that touches them: “If you feel it, call it." or “There is no such thing as a light blow.” Unfortunately, this directly contradicts the Society Rapier Rules, which say in part: "In rapier combat, blows will be counted as though they were struck with a real blade, extremely sharp on point and edge. Any blow that would have penetrated the skin shall be counted a good blow. Any blow that strikes a mask, helm or gorget shall be counted as though it struck flesh. Kingdoms shall not alter this standard.”
The crucial element there is “Any blow that would have penetrated the skin shall be counted a good blow.” So the question is: what does it take for an extremely sharp blade to penetrate skin? Fortunately, we have some good scientific data to answer this question.
 
In 1977, Dr. Bernard Knight, a British forensic pathologist, published an article entitled Some Medicolegal Aspects of Stab Wounds in Legal Medicine Annual, which dealt with this very question. Dr. Knight used a kitchen knife that was mounted into a spring-loaded handle during routine autopsies on human cadavers to determine the amount of force needed to penetrate the skin.
 
He found that if the point of the knife was placed against the skin, and pressure was applied gently, that it took about two kilograms (approximately four pounds) of pressure before the blade would penetrate. He also observed that “During the slow isometric application of pressure to the skin, the latter would dimple and the indicator gauge would rise to a threshold point when there was a sudden release of pressure, the knife plunging through the underlying tissues with no additional force. When a knife was pressed with only a single finger, the passing of this threshold point caused the knife to suddenly penetrate deeply into the body, even though the operator attempted to remove the pressure as soon as the loss of resistance was felt.” and that “During the experimental work it became apparent that the skin was by far the most resistant tissue, apart from bone and calcified cartilage. Once the knife penetrated the skin no further force needed to be applied to cause rapid penetration of the tissues beneath the skin.”
 
He found that the two most important factors in ease of penetration were the sharpness of the blade (which makes sense) and how fast it was moving. Quoting Dr. Knight again: “However, when a more realistic reenactment of the stabbing situation was simulated with a rapid lunge at the skin surface, a dramatic alteration of the usual result was seen. With the knife traveling at several feet per second, penetration occurred so readily that no reading was recorded upon the scale of the instrument. This was attributed to the inertia of the spring system, so that the knife did not begin to move relative to the handle of the apparatus before deep penetration was achieved.”
 
So how do these elements apply to calling blows in SCA rapier combat? First and foremost, remember that once a blade has hit with sufficient force to penetrate skin, it doesn’t really need more force to penetrate and cause damage. The notion that a blade would only penetrate half an inch past the skin surface is pretty unlikely—it's more like popping a balloon than hammering a nail. If it has the force to penetrate at all, it’s going to go deep.
 
But there is that “threshold point” for penetration that Dr. Knight described. Most hits in combat are going to exceed that threshold without any trouble, but there are times when you're at the extreme end of your opponent's reach, or he pulls the shot before it lands with any force, or you're moving back as the blow lands, where you may feel the point touch you, but a real blade hitting like that wouldn't have done any damage.


[[Combat Anatomy]] or "If that was a real blade, what would it have done to you?"
There is a difference between the amount of force required to feel a blade through clothing, and the amount of force needed to put a sharp blade through human skin.


[[A Treatise Concerning Leg Wounds]] By Don Aubrey de Baudricort and Joachim van der Haus
Try this experiment: Take a sharp knife (an X-acto knife is excellent for this) and gently touch the point of it. Can you feel it?—presumably—has it penetrated and drawn blood?—probably not. This "touch" can be felt, but it obviously isn't doing any damage. Now press gently on the point. Your skin will dimple in around the point, but it's still not being penetrated.


[[The Touch-kill Question]] Why "If you feel it, call it." isn't necessarily correct.
(Original page contained a broken image link with the caption: "Brand-new X-acto blade being pressed against my fingertip. Note how the skin is dimpling in from the pressure. However, the blade did not penetrate or draw blood.")
 
"If you feel it, call it" is saying, in effect, that just touching the point of a knife will do the same amount of damage as hitting your finger full force with the knife. Sorry, I don't buy that.


[[Testing lighter armor]] Is it possible to reduce the number of fabric layers in SCA rapier armor and still maintain safety?
[[Testing lighter armor]] Is it possible to reduce the number of fabric layers in SCA rapier armor and still maintain safety?


[[Schlager Penetration Tests]] By Don Robin of Gilwell


[http://web.archive.org/web/19990302032547/www.iceweasel.org/ek_schlager_test.html East Kingdom Armor Punch Tests] by Don Dylan ap Maelgwn and Don Thomas de Castellan
==Smashing PVC==
Testing the durability of PVC pipe as an SCA rapier scabbard used for parrying, under various conditions:
By Tivar Moondragon
 
This is a description of some tests on the durability of PVC plumbing pipe, in relation to how well it would work as an SCA rapier scabbard used for parrying.
 
Test #1 Plain PVC, at fairly high temperatures (mid-80s at a guess.)
 
I took a foot-long piece of 1/2" PVC pipe, clamped it into the vise on my workbench and tried whacking it with a wallhanger sword I just happened to have lying around. This blade is heavier and stiffer than any SCA rapier blade, and the edge is a bit sharper. On several attempts, all hitting it much harder than I would hit anyone on the rapier field--probably as hard or harder than I'd hit someone on the rattan field--I managed to crease and dent the PVC, but it showed no signs of breaking. Doing a similar-force blow on a piece of 2x4, the blade penetrated about 1/8" going across the grain of the wood and split a six-inch board completely when struck on the end.
 
The following morning, when the garage was ten or fifteen degrees cooler, I broke a room-temperature piece on the first hit. (Note that this was an older piece, so it may have photo-degraded to a greater extent.)
 
 
Test #2 Plain PVC, left in a freezer at 0 degrees for a couple of hours.
 
The first hit with the wallhanger shattered the PVC. One of the two larger pieces had a point that I wouldn't want coming at me at speed, even if I was wearing rapier armor.
 
 
Test #3 PVC with a single layer of duct tape over it. Three pieces, one left in the refrigerator (~40 degrees) one left in the inside freezer (~30 degrees) and one in the chest freezer (~0 degrees) overnight.
 
The three pieces I wrapped with a single layer of duct tape and put in the fridge, and both freezers last night all broke on the first hit, and the duct tape didn't do much to protect them.
 
 
Test #4 PVC with a spiral-wrapped double layer of fiber tape and a spiral-wrapped single layer of duct tape. One at garage temperature (morning, so around 75 degrees) one each put into the fridge and both freezers overnight. I also taped up a remnant of the older (and possibly photo-degraded) piece from Test #3 and left it at room temperature.
 
Hitting them with the wallhanger sword, all five pieces survived, with nothing beyond damage to the tape surface.
 
 
Conclusions:
 
1. Plain PVC pipe does seem to be rather fragile at cooler temperatures or if it's been out in the sun long enough to photo-degrade (and no, I don't know how long that would take.) While I doubt people would be doing too much fighting if it's below freezing outside, fighting at refrigerator temperatures--i.e. 30-45 degrees--is a distinct possibility (I've been to a number of tournaments where it's been that cold.)
 
2. Wrapping the PVC in a couple of layers of strapping tape with a layer of duct tape over it for cosmetic purposes does seem to protect the pipe quite a bit. I speculate that covering the PVC in leather would have a similar effect, or if it did break, the leather would contain the fragments, rather than letting them fly off into the crowd.
 
3. Mandating that scabbards intended for combat use be covered in leather or fiber tape is probably a good idea.


[http://web.archive.org/web/20050404020035/http://www.iceweasel.org/ek_schlager_mask_test.html Destroying Masks] By Fergus MacRae, and a team of Junior Scientists from the East Kingdom.


[ftp://ftp.cirr.com/pub/SCRIBE/Armory/Blades.Txt Historic blade weights and balance points] Comparing measurements of a number of historic weapons.
Commentary:


[[Smashing PVC]] Testing the durability of PVC pipe as an SCA rapier scabbard used for parrying, under various conditions.
While talking about this experiment at fighter practice, one of the other fighters showed me his scabbard, which is made from the polyethylene tubing used for sprinkler systems. This stuff is much more flexible and less likely to break. Another possibility would be CPVC pipe (the grey stuff, not the white) which, I'm told, is stronger that regular PVC. I didn't have any samples available, so I couldn't test this, though.





Latest revision as of 10:09, 11 May 2021

In SCA rapier, a Junior Scientist is someone who uses their academic or technical knowledge to test various questions about things like armor strength or blade behavior without the benefit of an actual laboratory. Typically their experiments are done in the living room or garage, using available materials.

An experimental archaeologist is someone who attempts to re-create historical artifacts using known or hypothesized historic techniques, rather than modern tools or methods.

Here are reports on some of their work:

(Editor's Note: I have reorganized the content to group broken links together and the text of sub-pages here to keep the topic together.)


Historic blade weights and balance points Comparing measurements of a number of historic weapons. (Broken Link)


Testing Lighter Armour

by Tivar Moondragon

Introduction

This is a description of tests I made in April of AS XXXVI (2001) as part of a discussion with Don Giovanni, when he was Deputy Society Marshal for Rapier. The Kingdom of Ealdormere had asked for permission to experiment with using lighter armor in conjunction with their heavier blades.

History

The standard body armor for SCA rapier has been four ounce leather, four layers of Trigger cloth or the equivalent, ever since rapier was first officially allowed by the Board of Directors back in AS XIV (1979.) That standard has been pretty well shown to withstand broken foil blades and most broken epees. (Problems can arise when an epee breaks with a jagged, rather than a flat point; the only two serious broken blade injuries in over thirty years of SCA rapier fighting have been from jaggedly broken epees.)

When schlager blades were introduced to the SCA, Junior Scientists in the East Kingdom tested them and determined that four ounce leather or four layers of Trigger cloth would also stand up to an untipped or broken schlager blade, thus, the standard continued as it was.

Over the years, however, questions would occasionally arise about the necessity of this "penetration resistant" armor against blades that tended to break less frequently that either foils or epees. The Ealdormere experiment was the culmination of those questions.

My concern, when I heard about this experiment, was that doing preliminary testing of a new type of body armor by taking it on the field for full-speed combat was not a good idea. The only way to find out that the armor didn't work would be through a catastrophic failure--the armor, and quite probably its wearer being penetrated--sort of like the Calvin and Hobbes method of finding out the load rating on a bridge.

So I decided to dust off my Junior Scientist hat, and do some tests under more controlled circumstances.

The Tests

One of the things the East Kingdom's Junior Scientists had found was that an untipped schlager blade actually penetrated fabric more easily than a broken one. Presumably this is due to the fact that the tip has a smaller cross section than a broken blade. I decided that rather than break any of my blades, I'd just remove their tips and test them that way.

Testing an untipped heavy blade against SCA rapier armor, wet rawhide and various combinations of rawhide and cloth:

I tried samples of 4 layers of Trigger and 4-ounce leather on The Machine, hitting it with full-force blows, trying to penetrate. I used my schlager; AEthelyan's schlager (the one affectionately known as "Rebar," which is way too stiff for combat, and spends its time over the mantelpiece) my Mark I Del Tin and my daughter Rosalind's Mark II Del Tin. All of these blades have the tips cut flat and the corners rounded just enough so that there's not a point there. "Rebar" has a tip profile of 3.5 x 10 mm, which is pretty large (the other schlager is 3.5 x 6 mm, my Del Tin is 2 x 7 mm and Rosalind's is 3 x 7 mm.)

On multiple hits, the best I managed was a few small holes in the top layer of the Trigger, (it looked like one corner of the blade had started to penetrate, but it was nowhere near enough for a downcheck if I was testing armor) and one pinpoint-sized hole in the leather. These hits were registering at 8 lbs and up, many maxed out beyond the scale's 18-lb limit.

Against plain wet rawhide (simulating bare skin) I managed to penetrate about half the time; those penetrations were all at 2 lbs. The other shots just skidded across the rawhide. I figure a similar shot would leave a nasty scrape on bare skin and probably a friction burn on skin covered with cloth.

Against the rawhide with a single layer of Trigger, I penetrated about 1/3 of the time. Those penetrations were in the 7-9 lb range.

Against the rawhide with a single layer of linen, I got one penetration at 12 lbs before I decided that the rawhide was too full of holes to continue (I kept getting false penetrations, where the fabric got pushed through an existing hole.)

Drop tests

I then decided to test in the opposite direction. I took the lead weight from my old drop-tester and mounted it on the various blades (sans hilts) that I was using, and dropped them down the tube from my drop tester onto fabric samples clamped over a piece of 4" pipe. Because of the slightly greater weight of the blades compared to the rest of the drop-tester, this gives an impact slightly higher than the 4 joules of a standard armor test, but it still has the advantage of consistency and minimum variables.

I tested Trigger, Judy Linen and some medium-weight cotton fabric. Each test consisted of dropping the weighted blade from a height of 30 centimeters onto the fabric sample three times and observing the results.

Four Layers

  • Four layers of Trigger passed against all four blades. (Twelve drops, zero penetrations.)
  • Four layers of linen passed against all four blades, although my schlager and Rosalind's Mark II Del Tin penetrated the first layer. (Twelve drops, zero full penetrations, two with top layer damage--which still passes the SCA drop test.)
  • Four layers of the cotton passed most of the tests. AEthelyan's "rebar" schlager damaged the first two layers of the fabric and my Del Tin penetrated completely on two of the three tests. (Twelve drops, two full penetrations, two penetrations of the top two layers--which qualifies as failing the SCA drop test.)

Three Layers

  • Three layers of Trigger withstood my schlager, was penetrated once by "rebar" and twice by each of the Del Tins. (Twelve drops, five full penetrations.)
  • Three layers of linen were penetrated twice by my schlager, had the top layer penetrated by "rebar", were penetrated twice by my Del Tin and once by Rosalind's Del Tin. (Twelve drops, five full penetrations.)
  • Three layers of the cotton was penetrated on all three tests by my schlager, "rebar" and my Del Tin, and on two of the tests with Rosalind's Del Tin. (Twelve drops, eleven penetrations.)

I didn't see much need to test one or two layers.

Conclusions

The "four layers of Trigger or equivalent" standard seems sufficient protection against a schlager or Del Tin that has lost its tip. This implies that it's sufficient protection against a broken blade as well, due to the larger cross-section involved, but I'd be interested to try this experiment with a broken Del Tin (considering that the only broken Del Tin I've seen had a sharp spur at one corner of the break.) Removing a single layer of fabric produces a significant increase in the likelihood of penetration (about 40%.) The threshold point for penetration seems to lie between three and for layers of Trigger. (This has been confirmed by independent tests done by Don Robin of Gilwell.) Combining the drop-test results with the Machine results, I think it's pretty clear that a single layer of Trigger, linen or other lightweight cloth will not reliably prevent penetration by an untipped blade. There was an injury in the Barony of the Stargate (Houston) in December of AS XXXIV (2000) which bears this out. A fighter was hit in the hand with a Del Tin that had lost its tip. The blade punched through his light leather glove, and penetrated about two inches into his hand. I think it's doubtful that two layers of fabric would be sufficient either. Three layers might be sufficient, but if "lighter" armor means it’s only reduced by a single layer, what's the point?

The Touch-kill Question

Why "If you feel it, call it." isn't necessarily correct...
By Tivar Moondragon

There is a belief in some SCA kingdoms that rapier fighters should call any blow that touches them: “If you feel it, call it." or “There is no such thing as a light blow.” Unfortunately, this directly contradicts the Society Rapier Rules, which say in part: "In rapier combat, blows will be counted as though they were struck with a real blade, extremely sharp on point and edge. Any blow that would have penetrated the skin shall be counted a good blow. Any blow that strikes a mask, helm or gorget shall be counted as though it struck flesh. Kingdoms shall not alter this standard.” The crucial element there is “Any blow that would have penetrated the skin shall be counted a good blow.” So the question is: what does it take for an extremely sharp blade to penetrate skin? Fortunately, we have some good scientific data to answer this question.

In 1977, Dr. Bernard Knight, a British forensic pathologist, published an article entitled Some Medicolegal Aspects of Stab Wounds in Legal Medicine Annual, which dealt with this very question. Dr. Knight used a kitchen knife that was mounted into a spring-loaded handle during routine autopsies on human cadavers to determine the amount of force needed to penetrate the skin.

He found that if the point of the knife was placed against the skin, and pressure was applied gently, that it took about two kilograms (approximately four pounds) of pressure before the blade would penetrate. He also observed that “During the slow isometric application of pressure to the skin, the latter would dimple and the indicator gauge would rise to a threshold point when there was a sudden release of pressure, the knife plunging through the underlying tissues with no additional force. When a knife was pressed with only a single finger, the passing of this threshold point caused the knife to suddenly penetrate deeply into the body, even though the operator attempted to remove the pressure as soon as the loss of resistance was felt.” and that “During the experimental work it became apparent that the skin was by far the most resistant tissue, apart from bone and calcified cartilage. Once the knife penetrated the skin no further force needed to be applied to cause rapid penetration of the tissues beneath the skin.”

He found that the two most important factors in ease of penetration were the sharpness of the blade (which makes sense) and how fast it was moving. Quoting Dr. Knight again: “However, when a more realistic reenactment of the stabbing situation was simulated with a rapid lunge at the skin surface, a dramatic alteration of the usual result was seen. With the knife traveling at several feet per second, penetration occurred so readily that no reading was recorded upon the scale of the instrument. This was attributed to the inertia of the spring system, so that the knife did not begin to move relative to the handle of the apparatus before deep penetration was achieved.”

So how do these elements apply to calling blows in SCA rapier combat? First and foremost, remember that once a blade has hit with sufficient force to penetrate skin, it doesn’t really need more force to penetrate and cause damage. The notion that a blade would only penetrate half an inch past the skin surface is pretty unlikely—it's more like popping a balloon than hammering a nail. If it has the force to penetrate at all, it’s going to go deep.

But there is that “threshold point” for penetration that Dr. Knight described. Most hits in combat are going to exceed that threshold without any trouble, but there are times when you're at the extreme end of your opponent's reach, or he pulls the shot before it lands with any force, or you're moving back as the blow lands, where you may feel the point touch you, but a real blade hitting like that wouldn't have done any damage.

There is a difference between the amount of force required to feel a blade through clothing, and the amount of force needed to put a sharp blade through human skin.

Try this experiment: Take a sharp knife (an X-acto knife is excellent for this) and gently touch the point of it. Can you feel it?—presumably—has it penetrated and drawn blood?—probably not. This "touch" can be felt, but it obviously isn't doing any damage. Now press gently on the point. Your skin will dimple in around the point, but it's still not being penetrated.

(Original page contained a broken image link with the caption: "Brand-new X-acto blade being pressed against my fingertip. Note how the skin is dimpling in from the pressure. However, the blade did not penetrate or draw blood.")

"If you feel it, call it" is saying, in effect, that just touching the point of a knife will do the same amount of damage as hitting your finger full force with the knife. Sorry, I don't buy that.

Testing lighter armor Is it possible to reduce the number of fabric layers in SCA rapier armor and still maintain safety?


Smashing PVC

Testing the durability of PVC pipe as an SCA rapier scabbard used for parrying, under various conditions: By Tivar Moondragon

This is a description of some tests on the durability of PVC plumbing pipe, in relation to how well it would work as an SCA rapier scabbard used for parrying.

Test #1 Plain PVC, at fairly high temperatures (mid-80s at a guess.)

I took a foot-long piece of 1/2" PVC pipe, clamped it into the vise on my workbench and tried whacking it with a wallhanger sword I just happened to have lying around. This blade is heavier and stiffer than any SCA rapier blade, and the edge is a bit sharper. On several attempts, all hitting it much harder than I would hit anyone on the rapier field--probably as hard or harder than I'd hit someone on the rattan field--I managed to crease and dent the PVC, but it showed no signs of breaking. Doing a similar-force blow on a piece of 2x4, the blade penetrated about 1/8" going across the grain of the wood and split a six-inch board completely when struck on the end.

The following morning, when the garage was ten or fifteen degrees cooler, I broke a room-temperature piece on the first hit. (Note that this was an older piece, so it may have photo-degraded to a greater extent.)


Test #2 Plain PVC, left in a freezer at 0 degrees for a couple of hours.

The first hit with the wallhanger shattered the PVC. One of the two larger pieces had a point that I wouldn't want coming at me at speed, even if I was wearing rapier armor.


Test #3 PVC with a single layer of duct tape over it. Three pieces, one left in the refrigerator (~40 degrees) one left in the inside freezer (~30 degrees) and one in the chest freezer (~0 degrees) overnight.

The three pieces I wrapped with a single layer of duct tape and put in the fridge, and both freezers last night all broke on the first hit, and the duct tape didn't do much to protect them.


Test #4 PVC with a spiral-wrapped double layer of fiber tape and a spiral-wrapped single layer of duct tape. One at garage temperature (morning, so around 75 degrees) one each put into the fridge and both freezers overnight. I also taped up a remnant of the older (and possibly photo-degraded) piece from Test #3 and left it at room temperature.

Hitting them with the wallhanger sword, all five pieces survived, with nothing beyond damage to the tape surface.


Conclusions:

1. Plain PVC pipe does seem to be rather fragile at cooler temperatures or if it's been out in the sun long enough to photo-degrade (and no, I don't know how long that would take.) While I doubt people would be doing too much fighting if it's below freezing outside, fighting at refrigerator temperatures--i.e. 30-45 degrees--is a distinct possibility (I've been to a number of tournaments where it's been that cold.)

2. Wrapping the PVC in a couple of layers of strapping tape with a layer of duct tape over it for cosmetic purposes does seem to protect the pipe quite a bit. I speculate that covering the PVC in leather would have a similar effect, or if it did break, the leather would contain the fragments, rather than letting them fly off into the crowd.

3. Mandating that scabbards intended for combat use be covered in leather or fiber tape is probably a good idea.


Commentary:

While talking about this experiment at fighter practice, one of the other fighters showed me his scabbard, which is made from the polyethylene tubing used for sprinkler systems. This stuff is much more flexible and less likely to break. Another possibility would be CPVC pipe (the grey stuff, not the white) which, I'm told, is stronger that regular PVC. I didn't have any samples available, so I couldn't test this, though.


(NOTE: This page from moondragon.info/wiki replicated with the authorization of Aethelyn Moondragon, 05/11/21. It is taken from a Wayback Machine imaging of Tivar's website dated August 15, 2020.)