Silk Stitched USN M-422A Jackets

[Maverickson]

Hi All,

It goes without saying, when using silk the stitch process is slower verses cotton. Which was the go to thread of choice at the onset of WW-2. As proven out with the limited work I have done with silk thus far. Because of the inherent constraints of slowing down the stitching process when using silk it was not exactly conducive to production work. More than likely exactly why it was dropped when production picked up for the War effort. Thereafter cotton was used for subsequent War era USN flight jacket contracts and the need for increased production. That is until the advent of nylon.

The image seen below comes from the the reverse side of the pocket and flap of my Monarch M-422. Note the shiny golden brown braided silk bobbin thread in the attachment. Difficult to at best to ascertain when viewed on the outside of an 80 year old jacket. That is until opened up and a point missed until my findings.

As compared to Monarch's immediately following mid War USN AN-J-3A 20570 contract. All of which was stitched in (flat colored) cotton thread. Taken from the exact same pocket and flap location and as seen directly below.

Cheers, Dave

 

[B-Man2]

Very informative Dave.... I enjoy learning about this type of restorative work.
Thanks for posting.

 

[Lord Flashheart]

Given how much is known about the A-2 and its predecessors In comparison this sort of detective work into USN jackets is simply fascinating and deserves credit. Thank you for sharing it here Dave. There’s a very interesting book on USN jackets that could be written here.

 

[Maverickson]

Hi All,

Currently, I've got a VLJ member (whom I will not name unless he posts a reply) trying to argue with me on the use of silk thread. Initially, he doubted my findings that these pre War USN flight jackets were in fact stitched in silk. Now he is doubling down. Only this time trying to argue with me that cotton thread is stronger than silk.

I've tried to explain the differences every which way but loose & no matter what I say or show him, he still maintains that he is correct in his assumption and I am wrong.

This fellow is continuously pinging me and I have grown weary of his logic. I would like to settle this once and for all. Since no matter what I say or do, he can not be convinced the silk (given relative diameters) is the stronger of the two threads.

Would anyone care to chime & contribute to this argument?

I am hoping that this doubting Thomas will read these replies & lets go.

Cheers, Dave

 

[B-Man2]

Dave
I’d guess that if the fellow isn’t going to take your word for it , there’d be very little that we could say that would convince him. Obliviously if someone like yourself , who has gone to extreme lengths , like going to the National Archives in Washington DC , to research component materials, contract dates and purchase documents can’t sway his opinion or change his mind , what chance would we have to possibly change his point of view . I understand your desire to help the fellow to understand the nuances of USN jacket manufacturing components, manufacturing and history but sometimes you’re better off just letting the individual maintain his own beliefs, no matter how sorted and incorrect they may be and to agree to disagree. There are some people you just can’t help in this world .

 

[Saint-ex]

Mechanical properties

Most silks, in particular dragline silk, have exceptional mechanical properties. They exhibit a unique combination of high tensile strength and extensibility (ductility). This enables a silk fibre to absorb a large amount of energy before breaking (toughness, the area under a stress-strain curve).


An illustration of the differences between toughness, stiffness and strength
A frequent mistake made in the mainstream media is to confuse strength and toughness, when comparing silk to other materials.[citation needed] Weight for weight, silk is stronger than steel, but not as strong as Kevlar. Silk is, however, tougher than both.

The variability of mechanical properties of spider silk fibres may be important and it is related to their degree of molecular alignment.[9] Mechanical properties depend strongly on the ambient conditions, i.e. humidity and temperature

 

[Saint-ex]

“Weight for weight, silk is stronger than steel, but not as strong as Kevlar. Silk is, however, tougher than both.”

 

[foster]

Silk is a stronger fiber than cotton, however cotton is the only natural fiber which becomes stronger when it is wet. Silk's main weakness is that it is easily deteriorated when regularly saturated by human perspiration. (I was a textiles major and I continue to work in what remains of the US textile industry).

I suspect the shift from silk to cotton was largely due to there being less of a domestic silk production industry in the USA, whereas cotton was abundant as the needs for wartime production became imminent.

 

[B-Man2]

Ok Dave
Try this .....Ask the fellow; if he was in a burning aircraft at 20,000ft and he had to bailout of that aircraft, would he rather have a parachute made of silk ..... or a parachute made of cotton... That’s it!! ......End of Conversation.!

 

[stanier]

Ok Dave
Try this .....Ask the fellow; if he was in a burning aircraft at 20,000ft and he had to bailout of that aircraft, would he rather have a parachute made of silk ..... or a parachute made of cotton... That’s it!! ......End of Conversation.!

Genius B-man2. Love it!

 

[Maverickson]

Hi All,

I really appreciate all your in put. You folks have reinforced what I have always maintained about those two threads.

This guy was going so far as telling me to correct this thread. Where I believe that this doubting Thomas went wrong is how he miss interpreted a report he came up with. That report directly compared silk to cotton thread. As it turned out & what I tried to point out to him (to deaf ears) was that he was comparing apples with oranges.

Where he went wrong is when he miss interpreted the specs. Problem being, he was looking at and comparing the strengths of large cotton thread diameters to a much smaller and in fact diminutive diameter silk.

Thereafter & no matter how I tried there was no convincing him otherwise. Maybe now he will review this thread again and come around to accepting the true facts.

It stands to reason that I can break # 16 (3 ply) cotton thread (what is generally used to stitch leather) in my hand with little or no effort. Something that is difficult to do at best with a comparable diameter silk thread.

Like they say, you can lead a horse to water but you can not make him drink. I'll leave it at that as I do not want to offend him.

Cheers, Dave

 

[foster]

The twist factor is a big component. You can't really compare different yarns with different twist and different diameter, and make an honest comparison. Take the two fibers, spin into identical size of yarn with the same twist, at the same temperature and humidity before testing the two. Otherwise you might as well be comparing a copper bar to steel cable.

 

[mulceber]

Like they say, you can lead a horse to water but you can not make him drink. I'll leave it at that as I do not want to offend him.

Yeah, it sounds like he’s managed to get his ego caught up in being right. Silver lining in the cloud, I suppose, is that his stubbornness was the impetus for you to do some great research.