Month: April 2023

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Phillosoph

Sharpie Skinwriter: A Proposal

Many Combat Injury-Immediate First Aid Kits (CI-IFAK) include a Sharpie marker in their contents.
This marker has a number of potential uses. It can be used to write tourniquet information on a casualty, mark an individual that has been administered morphine, or to fill in a casualty report card.
This role does not require a full-sized pen. Something about half the size would be sufficient. Is it worth creating a shorter pen to save just a couple of grams?
Our service-people are overloaded as it is, so saving a little weight where possible is prudent. When we consider whole companies and battalions being transported, saving a little weight for each person becomes a significant saving in fuel.
Creating a new model of Sharpie for this particular application also allows some useful new features to be introduced:
• The hue of human skin ranges from pale pink to dark brown. The colour of the “Sharpie Skinwriter” should be one that shows clearly on any tone of skin. This would probably be a light or medium shade of blue.
• The Sharpie Skinwriter would be approximately half the length of a standard Sharpie.
• Given that the user may be gloved and have their hands wet from blood, rain, snow etc, the cap and body of the Sharpie Skinwriter would be designed for easy manipulation under such conditions.
• Rather than grey, the body of the Sharpie Skinwriter should be made of a colour that allows it to be easily seen within the contents of the IFAK, even in diminished light levels. Medical/daylgo green is a possible choice.
My girlfriend took a look at this blog and presented me with this non-brand pen below. It is apparently used by tattoo artists.
It is 9 cm loa. The ring on the top could be used for a cord-pull loop, making it easier to remove when gloved. The barrel could do with some checkering to make it less slippery.

Pen used by Tattoo artists.

I have passed this idea on to the makers of Sharpies. Let us see if something comes of it.
Categories
Phillosoph

Shortening the Shovel

Back when I was much younger than I am now, I worked in many temporary jobs to support myself during higher education. Warehouses, bakeries, kitchens and hospitals, to name a few of the places that I worked.
I am above average height, so I soon became aware that many of the fixtures or tools I was expected to use were too small for me. Even in this day and age, items such as vacuum cleaners, mops and sinks are designed with the assumption that they will be used by average-sized women rather than persons of my size.
In many of the places where I worked it was not uncommon to see broom-handles extended with a length of pipe. Sadly many other tools were not so easily adapted.

A Little Off the End

Recently, someone was describing to me their early working life as a labourer on building sites.
From https://www.lilliputworld.co.uk/products/britains-navvy-standing-with-shovel-trade
“One of the first things you would do is shorten your shovel by an inch.”
Given my own early working background, it may not be surprising that I could not resist asking: “Which end?”
It turned out, it was not uncommon to shorten the shovel [spade] blade and resharpen the new edge.
Resharpening the edge made the tool more efficient and negated any neglect that a previous user might have inflicted.
It also lightened the shovel a few grams, and if you were expected to use a shovel all day, this weight saving was considered to be significant and worth having.
Of a similar ilk, cleaning the tool at the end of the day was considered important. A few millimetres of concrete drying on the shovel would add weight and make the shovel harder to use the next day.
This rather reminded me of the old adage about an ounce on the feet being like a pound on the back. A slight decrease in shovel weight may significantly decrease fatigue.

Less is More?

Logically, a shorter shovel/spade blade results in a smaller volume of material that is moved by each shovelful. Less volume means less mass, so each shovelful/spadesful took less effort to move. Thus a small decrease in blade-size might mean a significant reduction in energy needed to move each spadesful, since each spadesful would be lighter.
Of course, to move a given volume would take more actions with a smaller blade, but that may be more practical than moving it as a smaller number of much heavier loads. Are half-a-dozen light loads easier to move than three that are twice as heavy?
The following diagram may not be familiar unless you work in safety, or injury liability. It shows the recommended maximal loads that should be attempted by an average male or female.
Safe Manual Handling Limits
Maximum safe lifting is with the load close to the pelvis. The further the load is from this point, the less that can be safely lifted.
About 37% of work-related injuries are due to poor manual-handling practices, with a surprising number occurring in office and “white-collar” environments.
Based on the above, a shovel/spade-load and the tool being used to lift it should be around no more than 5 to 10 kilos in total mass.
In my blog on “Easier Entrenchment”, we encountered accounts of 19th century soldiers throwing up useful earthworks using trowel-sized bayonets. A narrower blade should penetrate packed earth better. Specially designed trenching shovels tend to have long heads than may be only four inches/100 mm wide. Very different from the modern, issued entrenching tool!
Can a smaller, more efficient shape make that much difference?
1873 trowel bayonet from https://worldbayonets.com/Bayonet_Identification_Guide/United_States__19th_Century_/us_19th_century_2_page2.html
All this suggests the basis for a really useful time-and-motion or ergonomics study.
What is the most effective way to throw up an earthwork with manual tools?
If the work is easier made in smaller rather than larger bites, what is the optimum size and shape of shovel blade?
I notice that some of the titanium tools on offer on the internet are not just lighter, but use blades of 200 x 90mm dimensions on a 64 cm haft.
Titanium-headed digging tool.
What is the best configuration and length of handle for a typical male?
Categories
Phillosoph

Webbing Gear and Ventilation

Recently I have been reading some new stuff on “cold-dry” or “snow” survival.
Dipping back into one of my older books, I noticed this caption on an image:
“Most soldiers trained in Arctic warfare prefer to keep their webbing attached to their backpack, rather than over their clothes, which restricts movement. ”
“Survival” (1988), Len Cacutt (p.124)
If it is acceptable to not wear webbing during Arctic operations, this suggests that it may be practical to do without many of the contents of the webbing during operations in warmer climes.
Given the date and origin of the book, the webbing referred to would be the British 58-pattern. Below is an illustration from the SLR-era. The following comments are still applicable to later systems and those of many other nations.
As can be seen from the illustration, webbing carried a lot of gear that was not immediately mission relevant.
Earlier in “Survival” there is a recommendation to “eliminate all non-essential items” (p.60). It then shows webbing loaded with wash-kit, stove, mess-tins, boot-polish, cutlery etc.
Part of the problem is the kidney pouches. Their large size is a temptation to load them up.
The pouches cannot be easily removed from the system when the weight they carry is not needed.
The position of the kidney pouches also hindered the use of efficient rucksacks that transfer the weight to the pelvis.
The consequence of all this is the webbing is heavy and bulky. It cannot be worn comfortably unless the belt is clinched tight, and it requires some system of yoke or suspenders.
In the SLA Marshall loadout recently described, a notable feature was carrying the ammunition only in bandoliers. No equipment belt is mentioned. Presumably there is one, since the soldier had to carry a water canteen and possibly a pouch for his pair of grenades. However, this belt would be relatively light without 80 rounds (about 5 lbs) of ammunition weighing it down.
Note in the photo below the GI wears a belt without any clip-pouches and does not use suspenders.
WW2 GI wearing bandoliers
Reading about pulks produced a similar observation from a Dutch source:
“As a result, Marines are now carrying a heavy backpack while moving on skis in snowy areas. An additional disadvantage of a complete package on the man is that the function of the worn clothing is not fully utilized (breathing capacity).”
In sub-zero operations it is important to avoid overheating.
Condensing perspiration can soak into clothing, reducing its insulating capability and chilling the body. This moisture can even freeze within the clothing.
There are a number of solutions to this problem. One is to not wear too much insulation. Another is to pay attention to the permeability and venting of clothes. Sweat must be prevented or allowed to escape the clothing before it becomes cold enough to condense.
It should be obvious that venting, air-circulation and removing excess insulation will all be hindered by the torso being constricted by a system of tight straps.
Air-circulation and heat-loss remain important considerations in warmer or hot-climates too.
Not only is what we carry important, but how we carry it!
Webbing/Load Carrying Equipment should be reserved for immediate-use mission gear. Items that do not qualify should be removed to a backpack. A small pack, or the detachable side-pockets of a large pack, can carry items for a 24 hour or CBRN (Chemical, Biological, Radiological, and Nuclear) operations
Decreasing the mass and bulk of webbing gear to improve air-circulation will greatly improve soldier comfort and performance. As a regular reader so eloquently puts it, it “reduces sweating without the benefits!”
A simple chest/belly rig, as described here, should be used for the primary ammunition supply. This will have three two-magazine pouches and a couple of smaller pouches for up to six (standard size) grenades, for example, two smoke and four fragmentation grenades. The only other features of the rig would be a snap-link, map/dump pocket, small weapon-cleaning kit, flashlight carrier and a mounting for a pec-knife. comms and first field dressing.
An equipment/waist belt would be lightly loaded with an CI-IFAK pouch and up to two litres of water.
In sub-zero conditions, water might be better carried in a bladder worn under the clothing to keep it liquid.
Possible additions to the equipment belt would be a handgun, handgun-magazines, long knife and possibly additional grenades and rifle-magazines. Extra munitions may be better carried by other means such as a claymore bag.
This configuration leaves the back clear for the more comfortable carrying of backpacks.