Butterfly size query

[SG500]

This one has me puzzled.
The 67 fuze has a diameter of 42.53mm at the widest point.
The 41 fuze has a diameter of 42.09mm at the widest point.

I've tried putting the 67 fuze in two different butterfly bomb bodies that are in good original condition and it doesn't fit (the fuze diameter is larger than the 42.40mm hole in the bomb body). The 41 fuze fits in both.

My query here is did they make different butterfly bomb bodies for the different types of fuzes?

The 67 will fit in a relic body but I suspect the reason for that is because the hole in the body has corroded sufficient for it to fit.

Dave.

 

[satan18]

This one has me puzzled.
The 67 fuze has a diameter of 42.53mm at the widest point.
The 41 fuze has a diameter of 42.09mm at the widest point.

I've tried putting the 67 fuze in two different butterfly bomb bodies that are in good original condition and it doesn't fit (the fuze diameter is larger than the 42.40mm hole in the bomb body). The 41 fuze fits in both.

My query here is did they make different butterfly bomb bodies for the different types of fuzes?

The 67 will fit in a relic body but I suspect the reason for that is because the hole in the body has corroded sufficient for it to fit.

Dave.

Hi Dave

I have a pair of standard 41s that are miles apart and they are both aparently standard fuses that have not been blown or distorted in any way.
The largest one will not fit full stop,even on a perfect charge body.
will post in near future.

I have found some minor differences on the 41a fuses that i have but have
put that down to the fact they have been in the ground and for some chemical reason they tend to swell a bit.

I would hazard a guess and say that they didnt make specific charges for fuses all be it being bayonet and screw fitting,as mass production could always be to blame.

Best phil

 

[Tmine35]

Knowing how perfect Germans were ( are ) in standardizing everything I'm sure here must be an explanation.

 

[butterfly]

Very good observation Dave,
Haven't given much thought to this before now!
I remember Paul posing a similar question in a past post - see link below

http://www.bocn.co.uk/vbforum/sd2-fuze-question-t20455.html?t=20455&highlight=fuze+size

Pauls link was on the 41 fuze with threads - now this I would expect to be standard on all bomb bodies as thread would be uniform- however the shoulder or top of the fuze could possibly have a greater diameter without affecting the fitting on this type.

The bayonet type fuze however is another matter, its the fuze head that is critical.

Am I right in thinking that the main part of the fuze body fits into the bomb body ok and it is the shoulder of the fuze that is the problem? (by shoulder I mean the widening of the top-not the two lugs used to locate the fuze into the bomb)

I have fuzes that I can fit in fine, but come to take them out again and its like a chinese puzzle, so exact is the fitting.
I can only assume that there are subtle differences in the shoulders and the tolerences are so fine that a minor difference of a few mm would mean that a fuze would not fit.
However like T-mine has pointed out the Germans are so precise with engineering that I doubt it was something that was overlooked.

I am trying to get as much information together as I can on complete 'untouched examples' to see if any manufacturers were combined in the assembly of the units. If this were the case then it would explain the minor differences in manufacture.

As for wether different fuzes of the bayonet type had different bodies, I would doubt that very much, the tolerences are just too fine. I think it would be more obvious in such a case.

I also have noticed on the bayonet type bomb body that when you try to insert a fuze with the clips attatched to the side lugs it is nigh on impossible to twist it round. Granted it would be a tight fit and a special tool was probably used, but on something as delicate as these fuzes the fit seems extremely tight. I've cleaned out the recesses to shiny metal and they remain impossible to twist by hand. I know that they would only be needed to fit once but always thought myself that this fit was extreme.

Not really helping much with your 67 though. Will have a look at the different bayonet fuzes in my collection and put them in different bodies and see if there are any apparant differences in the ones I have.

Great question you posed Dave
regards
Kev

 

[butterfly]

Hi Dave

I have a pair of standard 41s that are miles apart and they are both aparently standard fuses that have not been blown or distorted in any way.
The largest one will not fit full stop,even on a perfect charge body.
will post in near future.

I have found some minor differences on the 41a fuses that i have but have
put that down to the fact they have been in the ground and for some chemical reason they tend to swell a bit.

I would hazard a guess and say that they didnt make specific charges for fuses all be it being bayonet and screw fitting,as mass production could always be to blame.

Best phil

Phil,
Thats just blown my theory on the 41 screw thread right out the window!! would be very intrested to know what the markings are on the fuze head of the one that doesn't fit - also inspecters number in the waff mark (if you can read it)

One bonus of the intensive stamping that the Germans did on fuzes could trace problems back to the batch produced, but would assume any problems would be picked up at the inspection stage.

I agree with you on the bomb bodies, think any intended differences would have been much more obvious!

regards
Kev

 

[SG500]

Thanks for your thoughts Phil and Kev. I couldn't work it out either.

Kev the measurement is across the widest part of the fuze where it is curved i.e. if you look at where the number 67 and 41 is and draw a line across the top of the fuze its that measurement. It is NOT the measurement where the circular bit of the fuze sticks out where the clips are (are you following me here??). I agree that once the fuze is sitting in the bomb body it is usually very difficult to actually turn the fuze, this relates to getting it in the hole in the first place - the main body of the fuze goes in but not the top bit. If you look at the 2 photos you will see the one with the 67 fuze the fuze doesn't even fit into the bomb body, the second photo shows the same bomb body with a 41 in it. Both fuzes are extremely good condition and not distorted.

Makes you wonder what the measurements on a 70B are..........can anyone measure their one please......... Nismosonic...??

Dave.

 

[butterfly]

Thanks for your thoughts Phil and Kev. I couldn't work it out either.

Kev the measurement is across the widest part of the fuze where it is curved i.e. if you look at where the number 67 and 41 is and draw a line across the top of the fuze its that measurement. It is NOT the measurement where the circular bit of the fuze sticks out where the clips are (are you following me here??). I agree that once the fuze is sitting in the bomb body it is usually very difficult to actually turn the fuze, this relates to getting it in the hole in the first place - the main body of the fuze goes in but not the top bit. If you look at the 2 photos you will see the one with the 67 fuze the fuze doesn't even fit into the bomb body, the second photo shows the same bomb body with a 41 in it. Both fuzes are extremely good condition and not distorted.

Makes you wonder what the measurements on a 70B are..........can anyone measure their one please......... Nismosonic...??

Dave.

Hi Dave,

Yes I'm with you on this. Think your talking less than half a mm here, very fine tolerences.Even so you would have thought that they would have fitted with ease in all the bomb bodies. Especially being German.
I'm intrested to see also the screw-threaded 41's of Pauls and Phils that don't fit into bodies. I assumed it was the top that was too large now having read Phils response I think I may have been wrong to assume that.
You have thrown up a good question in this thread.
regards
Kev

 

[Nismosonic]

Thanks for your thoughts Phil and Kev. I couldn't work it out either.

Kev the measurement is across the widest part of the fuze where it is curved i.e. if you look at where the number 67 and 41 is and draw a line across the top of the fuze its that measurement. It is NOT the measurement where the circular bit of the fuze sticks out where the clips are (are you following me here??). I agree that once the fuze is sitting in the bomb body it is usually very difficult to actually turn the fuze, this relates to getting it in the hole in the first place - the main body of the fuze goes in but not the top bit. If you look at the 2 photos you will see the one with the 67 fuze the fuze doesn't even fit into the bomb body, the second photo shows the same bomb body with a 41 in it. Both fuzes are extremely good condition and not distorted.

Makes you wonder what the measurements on a 70B are..........can anyone measure their one please......... Nismosonic...??

Dave.

Hi.. i will measure it within the hour and post. it does fit into the body and twist some way but is very hard to turn though so I dont have it twisted in)

 

[Nismosonic]

70B fuze is 42.10 MM at widest point. I measured body hole as well as surely this is a factor here.. my bomb body hole is 42.5 mm dead. Body is stamped bdh 42 has lot numbers but no vissible Waff number this may be under paint if it has one.

i got out of bed to measure this, my wife not amused! LOL

 

[SG500]

70B fuze is 42.10 MM at widest point. I measured body hole as well as surely this is a factor here.. my bomb body hole is 42.5 mm dead. Body is stamped bdh 42 has lot numbers but no vissible Waff number this may be under paint if it has one.

i got out of bed to measure this, my wife not amused! LOL

Thanks for taking measurements Nismosonic and apologies to your wife!!
Sounds like your 70 has same measurements as the 41.
The 67 of mine wouldn't fit in the bomb body of yours if you bomb body measurement is 42.5 dead (the fuze is 42.53).............the plot thickens.
Dave.

 

[butterfly]

Intresting thread!!

I had a closer look at the bayonet type bodies in my collection and there appears to be a slight variation. One body (Rechlin origin) is much tighter fit on the fuzes. I have no accurate means to measure the difference, as we are talking 10ths of a mm, but a noticeable difference non-the-less.

Having looked at things a little more closely I would place the measurements as such:-

smaller diameter hole
(into which the main part of the fuze/gaine fits) - 37.5-38mm

larger size hole
(through which the whole fuze must pass) - 42.5 mm

measurement from lug to lug on fuze head - 45mm


Now please note that the above mesurements are taken as an average from what I have observed and therefore an educated guess to the actual figures.
I have looked through the paperwork and none of the diagrams I have on the SD2, have any diameter measurements for any of the above listed. (Maybe someone on the forum has more detailed diagrams with measurements?)

I would agree with Phil that there would be slight variations in the manufacturing process, so measurements would vary a few tenths either way.

Having said all this I would have expected the fuzes to fit into all bodies, no matter what, even given a few tenths either side. Also looking at the figures I have listed it would also give a margin of error in the manufacturing process.

So in answer to Daves original question as to wether or not there were specially designed bodies for the 67 and 70 fuzes, I think not. I also assume the differences in measurements are down to manufacturing, could be a 'bad batch' from time to time, why these should then be passed by an inspector is another question.

Please note that all the above is conjecture on my part, would love to know other peoples findings.

regards
Kev

I would just like to say to Nismosonic 'nice one', couldn't go to sleep with the burning question as to the measurement of the type 70 ! You must have a very understanding wife!!!!

 

[Nismosonic]

I have a theory...
your 67 fuze is of the very ealry type with the cast "Zeit" pointer.. maybe, and i say maybe this is a transitional fitting after the screw type, and is down to year or month made.. MAYBE the early bayonet bodies had a larger opening than the later bodies. As i stated earlier my body is stamped 42 and is 42.5 mill so would not accept your 67.. would be interesting if anyone who has a 41 stamped body could measure the opening. I believe the tolerance would be so small that all fuzes would fit into the early bodies, but only early fuzes fit into early bodies. I believe Fuzeman has a 67 of this type body also, could he measure his ?
I believe The fuze body components are made on a sub contract basis as mine is stamped underneath with a different 3 letter code than is on the top, so taking this in mind I would think that there was a standardisation as to the fuze body size.
As i said earlier, just a theory.. but only logical thing i can come up with. any body else ??

 

[butterfly]

I have a theory...
your 67 fuze is of the very ealry type with the cast "Zeit" pointer.. maybe, and i say maybe this is a transitional fitting after the screw type, and is down to year or month made.. MAYBE the early bayonet bodies had a larger opening than the later bodies. As i stated earlier my body is stamped 42 and is 42.5 mill so would not accept your 67.. would be interesting if anyone who has a 41 stamped body could measure the opening. I believe the tolerance would be so small that all fuzes would fit into the early bodies, but only early fuzes fit into early bodies. I believe Fuzeman has a 67 of this type body also, could he measure his ?
I believe The fuze body components are made on a sub contract basis as mine is stamped underneath with a different 3 letter code than is on the top, so taking this in mind I would think that there was a standardisation as to the fuze body size.
As i said earlier, just a theory.. but only logical thing i can come up with. any body else ??

Good theory Scott, see the logic behind it, unfortunately the 67 - as far as I am aware came into production during 1942.
I agree it would be intresting to see the measurements of Fuzemans 67 and bomb to see if there is any connection there.

regards
Kev

 

[Nismosonic]

Ive been looking at the photos of the post on the 67 fuze.. the step on the fuze body is definately larger than that on my 70, and looks same as step on fuzemans 67 of same type. see attached photos. my 70 in b&w and the two 67's in question.
I hope the owners of these photos dont mind me reposting these!
Interesting to see that the 2 67 bodies are slightly different, note on 1st there is a steep step, but on fuzemans there is a slope up to step as on my 70B. I do not have a 41B or the 67B minus the false Zeit pointer to compare these.

 

[millsbomber]

Just found This post, These fuses were also used for other bombs, not just the Sd 2s....... Dave

 

[SG500]

Just found This post, These fuses were also used for other bombs, not just the Sd 2s....... Dave

Thanks. The 67 at the start of this thread came screwed to an arming wire and a set of deformed wings, judging by the even amount of light corrosion, the fact the screw heads were mint and obviously not messed around with I think they all came together so this 67 was for an SD2. What other types were they used in? I seem to remember a post by Waff of a thing that looked like a large vane that had one in it.
Dave.

 

[millsbomber]

The Adapter for the 105 shell as picture used these fuses, i think the V1 used these types of fuses in the nose ???? the 2Kg Paravane bomb used the 70 B2, my 70 B2 measures 41.90mm at its widest point on the head....... Dave

 

[waffenamt]

Hi Dave,

That 'Vane' or 'Spinner' (as i call them) i have was to convert 88 and 105 projectiles to an airdropped bomb. The tails were also added and i believe then was designated SD-9?

#oops! millsbomber posting at the same time!#

cheers

waff

 

[millsbomber]

I brought a 88 and did not have much faith with the fuse adapter and no paper work to say it was fitted to 88s, i did have some paper work once about the 105 though..... Dave

 

[SG500]

Yep that's the one, thanks guys.
Dave.