Help Identifying German Magnetic Sea Mine Detonator device.

[flyboy2657]

Hello Everyone,

I'm seeking assistance w/regards to a WWII German Detonator piece in my collection.
I have attached many detailed photos. I'm certain that it is a detonator out of the LMB Aerial Delivery Magnetic Sea Mine. These were deployed by the Luftwaffe, in specially built Heinkel HE-115C-3 Mine Laying variant sea plane aircraft.
The only information I could find was quite minimal, this is what I know, it may be from a MK1 Magnetic Mine Type GA.
Does anyone know how rare this detonator is?
Also, does anyone know the collectors value and how rare this item may be?

This item was acquired from a 75 year old British gentleman, that has had it in his collection since he was 16 years old.
He acquired it just after WWII in Europe and held onto it, until recently when I acquired it from him.

It's very unique, and has a very intricate working mechanism, which still works!!! I can make the clockwork mechanism trip, and it starts ticking!
There are a couple of small arms that flip up and down while it is ticking. The unit will stop when a wheel with
a notch in the mechanism catches a lever trip arm and the unit stops. Very unique, and I'm thinking, quite rare piece.
There are many trip fuze mechanisms also on this device as well. A very interesting piece indeed!

Any help will be greatly appreciated, and by the way this piece is for sale, if anyone is interested.
This item is like new!

Cheers,
Andy
Canada:tinysmile_fatgrin_t

 

[John D. Bartleson Jr.]

Hi Andy,
Your Magnetic Flux Unit is used in a suspension cage in the GO Moored Magnetic Mine. The unit detected the presence of a ship but did not require the ship to be moving as in a magnetic induction ground mine.
The LMB and LMA mines used dip needles set in a dual gimbal and also detected the presence of a ship distorting the magnetic flux lines in the earth.
The 14 setting dial is the ship counter or ship eliminator unit used to confuse mine sweeping.
The spring wound unit o the opposite side is the sensitivity adjustment mechanism used to adjust the magnetic unit to its position in the earth's magnetic field so that any change in the earth's lines of flux would close a swtch and either count a ship or detonate the mine.
Hope this helps.
Regards,
John
P.S. I do not know the German designation of this firing mechanism.
oops: I failed to mention that the nichrome wire held between the two clamps located above the sensitivity adjustment mechanism is used to hold the mechanism in the fully wound position. When the first switch of the hydrostatic arming clock closes, the mine battery burns the wire apart and releases the spring to unwind and set the unit to the earth's field.

 

[flyboy2657]

Thanks very Much John for all your information regarding this item. Much appreciated!!!! What information links could I go to for more detailed information about this Flux Unit?
Also would you know if this item is quite rare? and possibly the value of such an item in the collector's world? Thanks again John you have been a great help.

I look forward to your reply, thanks.

Cheers,
Andy
Calgary, Alberta
Canada

 

[butterfly]

I think this is either the M3 or M4 unit - I would have to study it more to learn the difference, perhaps other members can tell you more, but as John has said this is for an influence moored mine rather than the airdropped version. - nice piece though in outstanding condition.

regards Kev

 

[John D. Bartleson Jr.]

Andy,
I am not sure how efficient the moored version of a magnetic mine would have been. This unit relies on a disturbance in the earth's magnetic flux lines to cause actuation. As a moored mine swings on its ancholr the Actuation mechanism inside the aluminum bouyant case is cutting these flux lines wheather this could be dampened is not known by me. Yours and the reference link by spotter is the only two I have seen. so for my point of view it is rare. However others may have seen more. As to its value, no idea, one man's trash is another's treasure.
German designation: M3 Magnetic Unit.
John

 

[flyboy2657]

Thanks Kevin for the clarification, much appreciated.
Cheers,
Andy

 

[flyboy2657]

Thanks John for the detailed cutaway view of the actual mine this Flux Unit is from. This helps plenty, thank-you. Also for the designation type, and answer about value.
Now I know it isn't that common an item to find.

Thanks again,
cheers,
Andy
Calgary, Alberta
Canada

 

[weberoed]

DESIGNATION. The Western Allies, during World War II designated these mines as type GO1, GO2, and GO3. In actuality these designations included two different mines; the submarine laid mine, designated SMA and the surface laid mine designated EMF by the Germans. The GO2 and GO3 mines are variations of the German
EMF mines.
TYPE. These were moored, buoyant, influence mines laid by surface craft and submarines. Although using different mooring systems, the mines were very similar in that they are all nearly spherical in shape. In addition they made use of the same influence firing mechanisms, carry similar explosive weights, and approximate one another in size. The mines were used against surface craft and submerged submarines in case depths and laying depths.
PAINTING AND MARKINGS. The submarine laid mines were painted dark green. The surface launched mines were painted light blue.
HAZARDOUS COMPONENTS.
The main charge consisted of 750 pounds of hexanite (13 percent HND, 63 percent TNT, and 24 percent aluminum powder). The charge was block fitted, in a charge container, inside the mine case, The weight of the booster charge was unknown, however, it consisted of picric acid pellets contained in a cylindrical can having a detonator envelope on its lower end. The mines used a single electric detonator; the weight and compositions of explosives are unknown. The mines were fitted with an electrically initiated explosive scuttling charge of unknown weight and composition.
DESCRIPTION.
The mine cases were aluminum alloy. The mine anchors were made of steel. The GO1 mine weighed approximately 1,290 pounds. The GO2 and GO3 mines weighed approximately 1,270 pounds without their anchors.
ARRANGEMENT. Picture shows the general arrangement of the GO1 and GO2 mines. The GO3 mine was similar to the GO2 but was spherical in shape and had no provisions for an 80-day clock. A cylindrical anchor designed for use from large vertical mine laying tubes of certain submarines formed a part of the mine assembly of the GO1 mine before laying. The GO2 and GO3 mine assemblies used a box like
anchor (surface laid) fitted with wheels to fit the mine rails of regular minelayers. These mines used magnetic needle type firing mechanisms. The baseplates could be fitted with self-destruct switches and/or antisweep switches.


ARMING. During the mooring and after laying the buoyancy of the case exerted a tension on the mooring wire of the anchor. Tension on the mine mooring pulled the mooring spindle of the baseplate down, tripping the booster release lever whereupon the booster seated over the detonator, and releasing the locking balls from the arming clockwork spindle. Water pressure of 15 feet depths, or
greater, then caused the clock to run. When the arming clock ran off its set delay period, the mine firing mechanism was activated to begin its arming cycle. During this delay period if the mine did not orient itself properly (after a preset period of up to 12 hours), a scuttling charge would fire to sink the mine.
When the firing mechanism was activated it proceeded to adjusts itself to the ambient magnetic field present and to then bias itself to the sensitivity desired. The mine was then armed.
FIRING. The mine would fire if a change in the earth's magnetic field occurs at the mine which is of proper polarity and intensity to close the magnetic needle switch of the mine's firing mechanism. As the mine could be readily swept by minesweepers it would fire on the first influence actuation received.
SCUTTLING. GO1 and GO2 mines were fitted with an 80-day mechanical clock which was designed to scuttle the mine upon completion of the set period.

Sorry pictures are bmp and can't get them to load right now

 

[John D. Bartleson Jr.]

Hi Weberoed;
Nice run down on the mines, what is your reference? Your BMPs might be too larbe for this forum. try a pixel width of 640.
Regards,
John
Andy:
P.s. The spring mechanism that adjusts the unit's sensititivity is termed the Automatic Latitude Adjustment (ALA) mechanism.
John

 

[weberoed]

years ago I came across a number of EOD pubs that had the RSPs and all classifeid info removed. My filing system really sucks but I found this one in a WW II folder, subfolder underwater mines Germany.

I'll try to reduce the BMPs, never have had any luck when playing with BMP

so how long you been retired now, think you were at the techcenter when I went through basic in 71

 

[John D. Bartleson Jr.]

Hello Again,
You have a remarkable memory. I retired on 30 the last day of 1984 at EOD Training and Evaluation Unit Two located at Ft. Story, VA.
In 1971 I was supervisor of Area 8, the Underwater Ordnance Practical Training and testing area. You would have only saw me in the Stump Neck mess hall. In 73 I was ordered by our CNO to serve as an exchange instructor at DEODS, Lodge Hil Camp, Chattenden, Kent, UK
May I ask how you obtained the pub (number?) ? Could it have been produced by the BD School?

Your name? You can PM if preferred.

Best Regards,
John

 

[weberoed]

for some reason the name just stuck with me. I've been collecting digital files for so lobng from so many people, ot just scanning hard copies that I don't remember where a large number of them came from. But I did get a load of files from a Brit EOD (ammo type) Warrant Officer about 12 years ago, strange he just disappeared and I never could find him after that. Collecting files is sort of my hobby these days, but I do have a small explsoive engineering/safety business - but it's been pretty slow lately (I don't do dud busting never was my gig).

 

[asiawatcher]

hey mate how much are you seeling it for ? cheers

 

[asiawatcher]

how much you sell it for? cheers

 

[flyboy2657]

how much you sell it for? cheers

Yes Item is still available. Price $2,000.00 US please advise if still interested, thanks.
Cheers,
Andy

 

[Fusse2004]

Wau!! The price of 2,000.00 -. $ Is madness! That was part of this year on a stock exchange for 200, - € discount.

 

[Natter]

Booktip on the topic:
"Technical Report #01 - Einsatzfhige deutsche Fernzndgerte Marine und Luftwaffe 1935-1945 - Magnetische, Akustische, Druck- und kombinierte Fernzndgerte von See- und Bombenminen" (Wolfang Thamm, 2005. ISBN 3-866-11-108-8 )

 

[EOD]

Booktip on the topic:
"Technical Report #01 - Einsatzfhige deutsche Fernzndgerte Marine und Luftwaffe 1935-1945 - Magnetische, Akustische, Druck- und kombinierte Fernzndgerte von See- und Bombenminen" (Wolfang Thamm, 2005. ISBN 3-866-11-108-8 )

Natter, it may be worth to mention that this book is merely a translation of the US manual. Please correct me if I am wrong.

 

[Natter]

Natter, it may be worth to mention that this book is merely a translation of the US manual. Please correct me if I am wrong.

I don't think so? The list of sources and references has 17 entries, and there is no US manuals listed there (three german dienstvorschrifte, the rest is misc books by german/us/british authors).

 

[EOD]

You may compare it to the US manual then. To me it looked like a knock off.