Flammenwerfer restoration project

[Bjørn]

Hi guys. I thought I'd post some pictures for the forum, of my newest weapon related project. This is the second model of the Flammenwerfer 41. (Dimas has previously posted a thread with some very nice pictures of the first model of this weapon in this forum section)
The difference between these two models is that the "strahlröhr" on the first model had a small hydrogen tank fitted, witch provides hydrogen gas for a small pilot flame for igniting the oil mixture from the main tank. The second model Strahlröhr wich came in 1942 (the model I have) has a very complex mechanism for fireing 9mm blank cartridges to ignite the oil, when the handle is pulled. I have actually been given a live original blank cartridge, from a fellow Norwegian collector. (pictured below)
Anyway, My FmW 41 has been put together by parts that I have found in both Germany and Norway. The Strahlöhr with the fireing mechanism was found in a well in Berlin under some construction work in 1978 (and is in remarkable good condition, and all parts seem to function as they should). The tanks also was found in Germany some years ago, and restored. (The large oil tank still have som thick smelly oil in it) The rare original carrying frame was found here in Norway just a few months ago, on a Norwegian military depot. (and I got that part for free) The labels on the tanks are not original (I made those om my computer from pictures of original ones, so they have the correct text on them)
The hose, wich connects the tanks to the Strahlröhr is unfortinently not original. It is just a plastic hose (with original fittings) that I use as filler for display, until I (hopefully) find a original hose to complete the set.
If any of the forum members knows of, or come across such a hose, I would be very interested :-)
I hope you like the pictures (although not the best quality)
Cheers
Björn

[Dimas]

Anyway absolutely nice item!
My dream is FmW 35
If ill find something for your I'll tell you.

[Michigan Dawg]

Bjorn, thanks so much for sharing such wonderful images of your flammenwerfer.

Do you have any close-up photos of the three text placards? I would love to be able to read the text on those.

Thanks again and congratulations on such a fine item in your collection.

[Tandiscum]

Hello, Bjorn, Your information is much appreciated. You are so fortunate in having a still functioning cartridge fireing unit, despite being stored in a well! I believe Mauser designed this mechanism, which the Allies desribed as most ingenious but very expensive to make, and having many small parts. I have seen German operating manuals, but never one which descibes or shows the mechanism. Do you know if drawings exist,or even have a manual detailing the operation of this mechanism? Perhaps you have taken a photograph of your firing mechanism, after removing the shroud? I have searched for a German patent without success. Perhaps you know that the 1942 model of the Swiss Sifrag flamethrower used a similar, but improved scheme. I have the operating manuals for the 1935 and 1942 Sifrag units, and shortly the detailed maintenence manual. I can send you a Xerox copy of any part of the manual, if interested, but I don't know how I would be able to send it to you. (I am a complete novice in computers, so I am ignorant of much of the "Bells and Whistles" on this advanced site!!) Thanks for allowing us to view such a well preserved specimen

[copdoc]

Hi Björn
Glad to see you here and still at work on your Flammenwerfer. You have done very well to collect the parts you have.

Does anyone know what kind of ignition system the Einstossflammenwerfer 46 has? (z.B, blank cartridge or chemical igniter?)

[Tandiscum]

Dear Copdoc,
The Einstossflammenwerfer 46 used a friction igniter, without delay, directly connected to the firing trigger. The igniter was mounted at the middle of the length of a chamber, bounded at on end by (I think) an aluminium bursting disc, and at the other end by a gas-producing charge. This latter was in a replaceable case closed at one end, except for a small orifice, initially closed by a celluloid disc. The charge had a central cavity running the whole length, so that the igniters spurt of flame lit the charge, causing the celluloid disc to burn through, and allow a jet of fire to contact the passing fuel stream.(The gas pressure and heat had melted the aluminium disc, so that pressure on the fuel extruded a rubber muzzle plug) The weapon could be reloaded. What amazes me is that the gas generating charge had two layers, the thinnest portion being nearest the small orifice, and also containing the greatest amount of metallic combustible powder. However, the rear layer still had such powder, though lesser in amount, and the gas and sparks bore directly on the fuel charge!
However, unthickened fuel normally was difficult to ignite, except at the muzzle, where spray was produce as a result of the first, slow moving part of the initial jet being impacted by the faster moving following portion. Thickened fuel ws, surprisingly, more readily ignited as it could contain a greater proportion of volatile (Petrol) fuel, since a high proportion of such in an unthickened stream would result in most of the "shot" burning before the target was reached.
Hope this is of help.

[copdoc]

Dear Copdoc,
The Einstossflammenwerfer 46 used a friction igniter, without delay, directly connected to the firing trigger. The igniter was mounted at the middle of the length of a chamber, bounded at on end by (I think) an aluminium bursting disc, and at the other end by a gas-producing charge. This latter was in a replaceable case closed at one end, except for a small orifice, initially closed by a celluloid disc. The charge had a central cavity running the whole length, so that the igniters spurt of flame lit the charge, causing the celluloid disc to burn through, and allow a jet of fire to contact the passing fuel stream.(The gas pressure and heat had melted the aluminium disc, so that pressure on the fuel extruded a rubber muzzle plug) The weapon could be reloaded. What amazes me is that the gas generating charge had two layers, the thinnest portion being nearest the small orifice, and also containing the greatest amount of metallic combustible powder. However, the rear layer still had such powder, though lesser in amount, and the gas and sparks bore directly on the fuel charge!
However, unthickened fuel normally was difficult to ignite, except at the muzzle, where spray was produce as a result of the first, slow moving part of the initial jet being impacted by the faster moving following portion. Thickened fuel ws, surprisingly, more readily ignited as it could contain a greater proportion of volatile (Petrol) fuel, since a high proportion of such in an unthickened stream would result in most of the "shot" burning before the target was reached.
Hope this is of help.

Thanks. Very interesting. Great detailed presentation on the device. Do you have a manual or a Einstossflammenwerfer 46 to examine?

Agree, I would think the lower vapor pressure of the thickened fuel would make it harder to ignite. Long time since PChem, but the fuel/air ratio is very important and too much fuel can in some situations be more difficult to ignite. Do you think the higher Pv fuels are just too fuel rich to easily light?

Was the "gas-producing charge" a pyrotechnic match?

Aluminum and celluloid burst valves would mean you really better trust the guys designing this thing. Would it be too much to ask for a schematic?

[Tandiscum]

Dear Copdock,
I have just lost my first entry, and didn't save same! More fool I!
No, I do not have a manual(Were they produced for the FmW46 at such a late date?), or the actual unit, if only! My information was gleaned from an Allied report at the Public Record Office, Kew.
There was a schematic attached to the report, but I was primarily searching for a manual on the Strahlpatrone mechanism, to no avail. The only bit that I didn't mention was a dip-tube leading back from the muzzle to the rear of the fuel container. Alright until you pointed the muzzle downwardly! Your point about vapour-rich mixture not inflaming made me realise that the hot gases and incendiary particles would be cooled in passing through the body of the fuel, so that when they emerged into the vapour space they would be safe.
The gas-producing cartridge was not a match, in the sense of the very ingenious igniter used on the M2A1, but like the Patrone shown in Bjorn's excellent pictures. The case had a screwed end, though, and no central brass lining tube, as used in the igniting cartridges used on the Japanese ROKS, Ack-Pack, and FmW41. (The Public Record office has reports containing sections of the Igniting Cartridges used by the Germans and Japanese).
Incidently, despite my best efforts, I cannot find a patent for the clever, noiseless, plastic bodied igniter used on the M2A1. Kilgore had a patent for a machine to coat the metal firing "Match" with varnish, adhesive and sand plus phosphorus, but that is all. Anyone have any other information?
I gleaned the fact that the Pv of unthickened fuel is less than thickened from an informative description covering the Wasp, a flamethrowing installation for the Bren carrier. (I had always thought that thickened fuel was difficult to ignite!)
I have just found that the Turks used a coal tar distillate, plus carbon disulphide, in WW1, and the Swiss used a mixture of Anthracene and carbon disulphide, in the '50's. Sounds expensive, but presumably was easily ignited. Anyone know why it was used?
Secondly, has anyone seen, or has access to, a TM covering the firing mechanism of the FmW41 mit Strahlpatrone. I have never seen one in the flesh, and I read that it is incredibly complex and ingenius.Perhaps a copy of that part of the manual? (Expenses covered!)

[Tandiscum]

Copdock-Correction. Japanese ROKS should read Japanese 93/100, ROKS. Sorry!

[copdoc]

Wie Gehts Tandiscum

There was a schematic attached to the report

How would one get a copy of this?

I didn't mention was a dip-tube leading back from the muzzle to the rear of the fuel container. Alright until you pointed the muzzle downwardly! Your point about vapour-rich mixture not inflaming made me realise that the hot gases and incendiary particles would be cooled in passing through the body of the fuel, so that when they emerged into the vapour space they would be safe.

That seems like a very complicated solution to a nonexistent question, why not a needle valve?

The gas-producing cartridge was not a match, in the sense of the very ingenious igniter used on the M2A1, but like the Patrone shown in Bjorn's excellent pictures. The case had a screwed end, though, and no central brass lining tube, as used in the igniting cartridges used on the Japanese ROKS, Ack-Pack, and FmW41. (The Public Record office has reports containing sections of the Igniting Cartridges used by the Germans and Japanese).

The M2 igniters are ingenious, I just wish I had more of them. Conceptually they are not complicated to make but quality control for such a project would be difficult.

How much do you know about the German Strahlpatrone? I woiuld be interested in hearing more about how it worked. Maybe Bjørn can tell us more about it. also.

I gleaned the fact that the Pv of unthickened fuel is less than thickened from an informative description covering the Wasp, a flamethrowing installation for the Bren carrier. (I had always thought that thickened fuel was difficult to ignite!)

I had thought that also. Will discuss it with some real chemists. It is an interesting concept.

the Swiss used a mixture of Anthracene and carbon disulphide, in the '50's. Sounds expensive, but presumably was easily ignited. Anyone know why it was used?

You would always guess, availability, availability and availability.
Antracene dissolved in carbon disulphide would be very corrosive and neurotoxic.

Secondly, has anyone seen, or has access to, a TM covering the firing mechanism of the FmW41 mit Strahlpatrone

That would be interesting to see.

PS Bjørn, If you think this is too off subject for your post I don't mind going to PMs and emails.