British Fuzes

[Bonnex]

A friend has just received several British fuzes (pictures below). The one next to the ordinary No 146 Fuze (Mark IV) is a No 146 Mark II in a spring loaded safety cover. I would be interested to know from any EOD personnel if any of these covers have been found in England, France or Belgium.

The others are a No 87 Mk I, No 106 Mk II, No 28 Mk I

 

[spotter]

Interesting Piece when i was working one of our regular clearance tasks recovering stokes mortars from a site here in the UK we only found them with the normal type 146 as shown and pistols

 

[MINENAZ16]

First time I see a cover for 146.

 

[doctor]

Hi
Never seen the 146 cover
N87 found on 60Pr shrapnel shell

 

[Bonnex]

Thank you gentlemen for your answers. I will try to research the origins of the cover and let you know if I come up with anything useful.

 

[MINENAZ16]

Hello Bonnex,

Could you show the fuze No146 MkII without the safety cover please ?

Regards

 

[Bonnex]

Minenaz16, Doctor and Spgr30,

Thanks for your interest in this. Herewith a few photos.

The history of this seems to start in December 1917 when the Superintendent of Design (Trench Warfare) and the Director General Trench Warfare wer tasked:

"to submit a design of the No 146 Fuze in which as few modifications as practicable are made, but in which the tape mechanism is omitted.

The components of the No 146 Fuze to be utilised as much as possible."

Three designs were drawn up on TWD5429 and submitted to the Trench Warfare Department in January 1918. The example would appear to be Design No 1.

 

[TimG]

Norman,

How is it meant to function?

Regards

TimG

 

[MINENAZ16]

I assume the original MkII is not like this one ; did they use a body of MkII for the new device (safety cover) ?

from BOCN :

Fuze, Percussion, Spigot, No 146
Design IDW B/65. CA.Vandervell design of allways fuze, similar in concept to the Fuze No 145 but using a ball. The mechanism consisted of a needle pellet and a detonator pellet, kept apart by creep springs. The needle pellet had a coned upper surface, and between this and the coned interior of the fuze nose was a steel ball. The two pellets were separated by a safety bar attached to a weighted tape. On firing the tape flew free and withdraw the safety bar. On landing, whichever was the uppermost of the two pellets would ride down and bring needle and detonator into contact. If the fuze landed on its side the ball moved across the coned surfaces and forced the needle pellet down on to the detonator. Broadly speaking this has been the operating principle of most allways fuzes ever since. For use with the 3in Stokes trench mortar
Mark WOLC
1 18496 of 21/1/1917 Introduction
2 22066 of 24/3/1919 Longer safety bar, shorter needle holder.
3 22066 of 24/3/1919 Built-up needle holder instead of aluminium casting
4 22066 of 24/3/1919- Modified needle holder; detonator closed by tinfoil disc.
5 22066 of 24/3/1919- Aluminium needle holder, shortened safety bar
5R A2732 of 14/3/1927 Mk 5 with a steel, instead of the-cast, cap.
5R* Not formally introduced; no record.

Mark 1 Obsolete: 24753 of 30/12/1921
Marks 2,3,4,5 Obsolete: A7676 of 21/1/1933
Marks 5R, 5R* Obsolete: C3936 of 26/9/1949 "

 

[Bonnex]

Tim,

I will need to dig out some TWD minutes. I have sort of worked it out but cannot yet see how the safety bolt in the 146 fuze is ejected since there is no spring to do this.

Back to you later in the week.

 

[Bonnex]

I assume the original MkII is not like this one ; did they use a body of MkII for the new device (safety cover) ?

from BOCN :

Fuze, Percussion, Spigot, No 146
Design IDW B/65. CA.Vandervell design of allways fuze, [...]
Marks 5R, 5R* Obsolete: C3936 of 26/9/1949 "

Yes, the idea was to use standard components and the Mark II was current at the time of the design. The notes are probably from me. Although CA Vandervell is credited with the 146 design in the notes the designer at CAV was Albert Midgely. Midgley (engineer) teamed up with Vandervell (business man). Midgley was a prolific inventor and his patents are well worth a look (car dynamo, fuzes in both world wars, single valve radio, first electronic organ, W Bomb etc).

 

[Millsman]

Old thread updated.

I've just found one of these No 146 Mk I caps at a fair in France (Somme) dated 5/17 - maker CAV.

Will try to put up a photo tomorrow.

John

 

[Millsman]

From the comments 1-5, I assume these are rare, or is that just the Mk II onwards?

Here the photos. I picked it up in the Abbeville militaria fair on Sunday.

John

 

[AMMOTECHXT]

John, your first photo shows that the safety cover has been in a detonation, so I guess it must have been fitted to a Stokes mortar or whatever the fuze was used with when it came to grief.

 

[Millsman]

Mmmm. Not sure about that. The threads are intact and it looks more time damaged than explosion damaged. More a relic.

John