Casting nose plugs

[Gspragge]

I may have to reproduce a couple of plugs of an impossible to find form from an example on hand.
The plug or a brass dummy fuze of the same form could be turned if I knew some one to do it. Has any one any casting
experience ? The medium would be pot metal, the kind of stuff Dinky toys are made of - or similar.

 

[kahu1]

I haven't tried metal casting but believe the harder/ tougher grades of silicon moulding rubber can be used.
The only casting i've done has been in resin, supplies obtained from the local model shop.

cheers
Bob

 

[Gspragge]

If it fits, this is the plug in question.

 

[Falcon]

To make this plug from a casting would require finish machining as well. The thread would be almost impossible to cast correctly. To produce two of them you would be better off finding someone who can make two of them from brass rod on a lathe.

If I had some measurements (particularly the thread specification), I would possibly be able to do it for you.

 

[2pounder]

I'm with Falcon on this, to cast threads is difficult unless pressure die cast. but machining the wrench pockets is tricky without a milling machine. So why not try casting a plug less thread but with a slave piece on the end , machine the thread possibley die cut , them machine off the slave piece.

 

[Falcon]

Sorry I didn't see that it was pot metal.

The closest thing to pot metal would be turning zinc rod if you could find it.

 

[Gspragge]

I have to wait to find out if this is the correct fuze type, but so far it is the likely candidate. The threads might be a standard metric size in which case they could be die cut. Or if poorly cast, cleaned with a steel nut with slots cut into the threads, it would act as a cutter on the softer metal. I should know early next week.

 

[Falcon]

If I can find some zinc rod I would try turning one. Casting seems an extra unnecessary step when only two need to be produced.

You can buy 500mm of 20mm diameter zinc rod here on ebay for 11.70 plus 8 postage.

http://www.ebay.co.uk/itm/Custom-wa...tEquipment_Accessories_SM&hash=item2ea965356c

100mm of it would probably be sufficient for making two 37mm fuzes. I will ask around and see if I can find an offcut somewhere.

 

[Falcon]

I found that a UK company called RS sells 300mm lengths of 20mm diameter cast zinc rod for 8.99.

 

[2pounder]

you can get a metal alloy that melts in water as we used it to bend small tube but where it comes from now not a clue. probably banned as it had lead in it.

 

[raymeketa]

2pounder

You're probably thinking of a product called Cerrosafe. Used for making chamber casts. It would probably work but I don't know where you'd get a round bar. And, it is expensive. Here in the US it costs about $35 per pound. A similar metal is Woods Metal. It does contain lead.

Gspragge

Have you considered aluminum? Readily available and cheap. Anyone with a lathe could make two replicas for you in short order. I could make them for you but, if I did, I would want to have an original in hand to duplicate, exactly. Especially the thread. It doesn't take much of an error in thread diameters or pitch to result in a non-fit.

Ray

 

[Gspragge]

It turned out to be a wooden plug !

This was not a fuzed projectile and had a wood fuze shaped plug. It appears that it was forced into the body and the sides have been sheared off. One was removed from the body, but too damaged to work things out. So perhaps if the other one can be freed intact a better idea can be had. Shown is an intact example from the same kind of projectile. But with a Crown mark on the base- does any one recognize it.

 

[Weasel]

edHi Gordon,
I have seen one of these recently with a brass sprung loaded plunger type arrangement which seemed to grip the inside of the nose cavity if it is pushed in making it rather difficult too remove again so i was told. I will ask if he took any pictures of it removed from the projectile hopefully he did. Here is one of the plug in situ that i took,
Best regards Weasel.

 

[beihan62]

Hi Gspragge,I have a small quantity of "cerrabend"it was given to me some years ago by an engineer from the Perkins engine factory,it is I think the same as"cerrosafe",I have no idea how to use it but if it is any use to you for the job in hand let me know,I think there would be just about enough to make a couple of nose plugs,you would need to get advice as to how to use it as I do not have a clue,it is the same colour as Mazak/zinc alloy,hope this is some use to you,
Regards,Don,

 

[hangarman]

From memory Cerrabend melts in boiling water. Make a mould from silione, melt your cerrabend and pour it in!
Hangarman

 

[Gspragge]

Design Number

The number indicates that the design of this was registered in 1900. How ever what the design was is another matter. This is likely a surplus projectile and the design likely relates to some souvineer modification as yet unknown. The records exist and this can be found out. This is the third such 1900 37mm projectile with a design number I know of. I have a candle stick, there is another on a brass base and now these, I have seen others but this is the first with a number and a nose. I will find out where the records are kept, if a member is close it would not be difficult to look these up and find out what the design description was and who was doing all of these.

This is where they are -- The National Archives, Kew, Richmond, Surrey, TW9 4DU is there a member nearby ?