Strange Item

[S6PNJ]

My grandad was an avid model maker and sadly passed away earlier this year. I inherited all of his model making tools and am just looking at some of them to see what I wish to keep and what I'll look to pass on etc. I've come across a small red plastic item that at first I thought might be a knife sharpener, but on closer inspection (and having taken it apart), I'm not so sure - in fact I'm pretty sure it's not a knife sharpener!

It has the name ROSMIC on both sides of the case and has a part number of M41/501B stamped on the inside of both case halves. The inside has some spring type elements but I can't see the purpose of them.

Anyone any clues as to what its use is? It is roughly 1 3/4" by 1" in size. Click photo for bigger pic.

[Eric Mc]

A thread cutter?

[shortar53]

My first guess would be a safety knife / cutter for plastic wrapping and packaging - is the "bit" in the middle sharp?

similar to this maybe?
http://www.kilby.co.uk/packaging-products/safety-k...

[S6PNJ]

shortar53 said:

is the "bit" in the middle sharp?

No, not at all. it is a piece of brass that has been folded in two so could open out flat with the 'exposed' bit (the bit at the top in the gap of the plastic) being in the middle. IE the bit you'd expect to put a knife blade to when 'sharpening' is a folded piece of brass. Having played a bit more, if a small sharp point (sewing needle type affair?) was pushed in from the right, the brass piece would pivot to the left and a blade(?) could then be pushed down brass piece. I'm still none the wiser as there is no 'sharpening' ability in brass and there are no hardened edges etc to sharpen against.

[SAB888]

Complete guess. Anything to do with electrical wires to test or make a circuit?

[Zad]

Does it say "UK Pat 620416" on it? Nothing came up on a patent search for that, so I may have the number wrong.

[williredale]

Judging by the internals it's something electrical. It's not a fishing bite alarm is it?

[Zad]

It looks more like a simple wire stripper or maybe a letter opener.

[S6PNJ]

Zad said:

Does it say "UK Pat 620416" on it? Nothing came up on a patent search for that, so I may have the number wrong.

I've put it down somewhere (busy tidying and moving stuff) and of course, now I can't find it again! Arrgh!

[SAB888]

S6PNJ said:

shortar53 said:

is the "bit" in the middle sharp?

No, not at all. it is a piece of brass that has been folded in two so could open out flat with the 'exposed' bit (the bit at the top in the gap of the plastic) being in the middle. IE the bit you'd expect to put a knife blade to when 'sharpening' is a folded piece of brass. Having played a bit more, if a small sharp point (sewing needle type affair?) was pushed in from the right, the brass piece would pivot to the left and a blade(?) could then be pushed down brass piece. I'm still none the wiser as there is no 'sharpening' ability in brass and there are no hardened edges etc to sharpen against.

Could the brass bit be where wire is gripped and the insulation pulled off? The spring and brass thing would push against the wire to hold it in place?

[MrCarPark]

It looks like a threader for needles or fish hooks/flies etc.

[S6PNJ]

S6PNJ said:

Zad said:

Does it say "UK Pat 620416" on it? Nothing came up on a patent search for that, so I may have the number wrong.

I've put it down somewhere (busy tidying and moving stuff) and of course, now I can't find it again! Arrgh!

Found it again! It say UK PAT 620816 from what I can make out - very small lettering as you can see from the pictures.


Having now searched for this, I think I've found it!
http://worldwide.espacenet.com/publicationDetails/...

It is a needle threading device - just need to see if I can get it to work now!