Centre Tube... No. 5 vs No. 36

[staples57]

I have two projects on the go right now.
a) Restoring a JPS No. 36M Mk 1 Mills training grenade
b) Restoring a No. 5 Mills that was turned into an ashtray and nickel plated. It looks like more of a post war factory job than trench art.

The restoration of the 36M Mk 1 training grenade is relatively straight forward and progressing nicely.

The restoration of the No. 5 is becoming a real challenge (I love a good challenge!). When I originally found & purchased it, there was only the No. 5 casting, filler screw and an unmarked base plug. All original to the period, but possibly not original to the casting. All the internal bits were missing.

Since then, I've been able to find a No. 5 striker and spring.
Gothica7 is helping me locate a No. 5 lever. Thanks mate!

Unfortunately, a No. 5 center tube is next to impossible to find (in Canada).
I've found a No. 36 center tube ("ADC 43 Z" marked) and was planning on using this until I locate an original No. 5 center tube.

My questions...
a) Is there such thing as an original JPS marked No. 36 lever?
b) Is there a difference between a No 36 & No. 5 Center tube?
...for example, is the No. 5 center tube shorter than the No. 36?
c) What's your opinion / suggestion... use a No. 36 center tube with my No. 5 or not?

As always, any information is appreciated.

 

[gothica7]

Hi bud,

good luck with your restorations.

There is quite a difference in centre tubes. Most No 5s had an aluminium tube as opposed to a 36 and many No 5 tubes were akso made of brass. Also later in 1916 some were made of lead antimony as there was a brass shortage. I have 3 of these and you are welcome to some piccies but not the tubes as they are as rare as hens teeth. A 36 tube from WW2 will fit ok but it would just not be right. You may be lucky enough to source a WW1 36 tube made from aluminium[they look just like a WW2 tube] but again it would not be right for a No5. If i had a No 5 tube i would let you have it but will keep my feelers open for you. Time will tell and you will get one, if i can help i will let you know. In the mean time, a 36 tube will fill the gap, if you have one.
No 5 tubes are becoming harder and harder to get hold of these days.

I havnt seen a Josiah Parkes lever before, although this dosnt mean they dont exist.I think they just made the bodies. My Ex was of this family, she told me they were originally locksmiths, my investigations proved her right but she never realised they were into munitions as well.Just as well.

Good luck.

Andy

 

[staples57]

Thanks Andy, much appreciated.

The No. 36 center tube I have fits the No. 5, but it appears to be a little too long. When threaded completely into the Mills and a drill detonator (Mk. III for a No. 36) inserted, you can't install the base plug.

Would you be able to measure the height of one of your No . 5 center tubes?
...my No. 36 center tube is 6.8cm in height.

Thanks,
Brad

 

[staples57]

I haven't been able to find any technical data / dimensions for the different center tubes.
Does anyone have a No. 5 & No. 36 center tube that they could photograph side by side for comparison and post?

From the photos I've seen of the two center tubes, it looks like there are slight differences. for example. it looks as if the center "stem" on the No. 36 is longer than the one on the the No. 5. It also looked like the fuze "hollow" or recess was deeper on the No. 5 (also more threads on the No.5).

Cheers,
Brad

 

[paul the grenade]

here you go staples.
the left is a 3 piece brass from a No5 the centre is a 1 piece alluminium casting from a No23 mk2 and the last is cast zinc from a No36m.
cheers, Paul.:tinysmile_fatgrin_t

 

[lexpev]

centre tube

I grabbed for a pint and suddenly some sort of aluminium centre tube came rolling from between the carrots and the undefinable spread cheese.
PM me, postage is three beers.
Lex

-no heineken, I have taste-

 

[staples57]

Great pics, thanks Paul. That's exactly what I was hoping for.
The No.5 center tube looks like it's slightly taller than the No. 23 and No. 36. If it's not too much to ask, would you be able to measure the height of the three center tubes??

I may have a case of mistaken identity. I thought I had a No. 5 Mills, but I'm not sure. The attached pic is of the Mills that I'm trying to restore.
Do I have a No.5 or No.23?

What do you think... ???

here you go staples.
the left is a 3 piece brass from a No5 the centre is a 1 piece alluminium casting from a No23 mk2 and the last is cast zinc from a No36m.
cheers, Paul.:tinysmile_fatgrin_t

 

[paul the grenade]

i'll measure them later and let you know.
its hard to tell your gren. the only clue is the slotted striker which was a later modification on the 23's. what has the base plug got stamped on it?
cheers, paul.

 

[paul the grenade]

have you been DRINKING AGAIN Alex !!!!!!!:neutral:
Cheers, paul.

I grabbed for a pint and suddenly some sort of aluminium centre tube came rolling from between the carrots and the undefinable spread cheese.
PM me, postage is three beers.
Lex

-no heineken, I have taste-

 

[gothica7]

Hi Brad,

do you intend to try and make the grenade whole again? If so, you have your work cut out[sorry] and if i were you i would clean it up, yes, and it should make a good cutaway. Looks pretty sound from the picture and as Paul says, difficult to say what Mark of Mills. If it has a No5 plug then its a No 5. Also looks pretty good as an ashtray, many of which were made after the war. It hasnt had the other side slightly flattened in any way has it? This would confirm the ashtray. I see there is some sort of brass stud visible in your picture. Was this to attach it to a base? I reccon it may have been turned into an ashtray. You dont see many about, rare enough in itself and perhaps should be left as such. Just my thoughts.

Good luck with it.

Andy

 

[staples57]

Thanks Paul. The striker was my addition and not original to the gren... I'll swap it out with an unslotted striker. The base plug is unmarked.
/Brad

i'll measure them later and let you know.
its hard to tell your gren. the only clue is the slotted striker which was a later modification on the 23's. what has the base plug got stamped on it?
cheers, paul.

 

[staples57]

Thanks Andy. The gren is nickel plated, other than that it's un-damaged (nothing flattened). I believe at one time the section cut-out was used as the stand and therefore the reason for the brass rivet/stud. It has a No.5 unmarked base plug without any threaded hole for a launghing rod. Original to the gren when I got it. The only addition that I made was to add the slotted striker. Thanks to Paul, I now know that a slotted striker is incorrect for a No.5 gren. I'll swap it out for an unslitted striker tonight.

To me, it looks as if it was made post war, possible factory made. I've seen one very similar (not nickel plated, but with the same style filler plug and base plug) that was describes as a post war factory made "Souvenir of the Great War".

If I can find No.5 or No.23 center tube in good condition, I wouldn't want to cut it. Just add it back to the gren and make a nice display piece.
On the other hand, if I find a center tube in rough/poor shape, then a cut-away of the center tube may be the direction I'll go in.
It all depends on the condition of the center tube.

Thanks,
Brad

Hi Brad,

do you intend to try and make the grenade whole again? If so, you have your work cut out[sorry] and if i were you i would clean it up, yes, and it should make a good cutaway. Looks pretty sound from the picture and as Paul says, difficult to say what Mark of Mills. If it has a No5 plug then its a No 5. Also looks pretty good as an ashtray, many of which were made after the war. It hasnt had the other side slightly flattened in any way has it? This would confirm the ashtray. I see there is some sort of brass stud visible in your picture. Was this to attach it to a base? I reccon it may have been turned into an ashtray. You dont see many about, rare enough in itself and perhaps should be left as such. Just my thoughts.

Good luck with it.

Andy

 

[gothica7]

Hi again Brad,

been thinking about your No5 whilst following lawnmowers about all day and i reccon the reason a centre tube n a det wont fit properly is that the gren failed quality control and thats why it was turned into an ashtray. The only way to make a tube fit would be to cut off part of the lip at the top and Bob's your uncle. A 36 or a 5 tube should fit as they are interchangeable and the same size give or take a millemetre or 2 which should not be a problem. I have found each type of tube in each type of gren and the dets fit no worries. I dont think you need to worry about the exact measurements of each tube unless you plan to make one.

Andy

 

[staples57]

Cheers Andy. That makes a lot of sense, never looked at it that way.
Now that we can explain the the "why" i can concentrate on the "what"... finding a No.5 centerpiece.

Thanks,
Brad

Hi again Brad,

been thinking about your No5 whilst following lawnmowers about all day and i reccon the reason a centre tube n a det wont fit properly is that the gren failed quality control and thats why it was turned into an ashtray. The only way to make a tube fit would be to cut off part of the lip at the top and Bob's your uncle. A 36 or a 5 tube should fit as they are interchangeable and the same size give or take a millemetre or 2 which should not be a problem. I have found each type of tube in each type of gren and the dets fit no worries. I dont think you need to worry about the exact measurements of each tube unless you plan to make one.

Andy

 

[paul the grenade]

heres the centre tube measurements.
sorry for the delay.
brass one is 68 mm high
alloy one is 69 mm high
and the zinc one is 68 mm.
not a great deal of variation even though the alloy one has much deeper threads.
cheers, Paul.

 

[staples57]

Thanks Paul.
Do you think that there was any fitting the centerpiece to the casting?
...trinning the centerpiece to fit?

/Brad

heres the centre tube measurements.
sorry for the delay.
brass one is 68 mm high
alloy one is 69 mm high
and the zinc one is 68 mm.
not a great deal of variation even though the alloy one has much deeper threads.
cheers, Paul.

 

[paul the grenade]

I cant see the factories checking each one for exact length. they made that many that there was probably a lot of slight variations in batches.
Ive looked at my mills grens and some base plugs screw in a long way and others have threads showing when fully tightened.
cheers, paul.

 

[staples57]

Thanks Paul. I appreciate all the info.
The variations in manufacturing make collecting both interesting and very frustrating. I love a good challenge.

Cheers,
Brad

I cant see the factories checking each one for exact length. they made that many that there was probably a lot of slight variations in batches.
Ive looked at my mills grens and some base plugs screw in a long way and others have threads showing when fully tightened.
cheers, paul.

 

[Fragman]

Hi, As with all munitions, the inserts were made to very exacting standards. They were indeed individually inspected and sized. The need for quality gauges was one of the grenade manufacturing bottlenecks in New Zealand at the start of WW2 and a major delay to mass production. Attached is a series of photographs depicting the inserts being made here in NZ (hopefully they are not too small). Enjoy

 

[Bonnex]

No 36 Centre Pieces

The specs for British service ( which presumably serves pretty well elsewhere) dictate that the length of the centre piece should be between 2.66-inches and 2.68-inches. This applied to CPs used in the No 23 Mk III and No 36 Mk I. Info correct January 1919. I expect the WW2 and 1960 specs give the same value but my drawings for these are away on loan at the moment.

No 5 through No 23 Mk II grenade CPs were spec'd at Low 2.71-inches, High 2.73 inches for aluminium.