If 55 (ish) year old memory is to be trusted it looks like the one in the monster box of Meccano that was passed down through the family until binned by the unthinking cousin who got it after me.

Not a Meccano one as it wouldn't fit when I tried to build one or two of the models either out of the really advanced Meccano books or from Meccano Magazine.

Presumably Meccano compatible motors could be got from other suppliers, possibly as a cheaper option.

Clive.

It's very well made, not a toy originally. I suggest it was a war surplus item, probably aircraft. I don't recognise it specifically though. Anyone got any old Proops or "Service Trading Co." catalogues?

Robert.

Very common to find motors adapted for use in a Meccano model or Meccano, especially gears, used to make something real, or for prototyping.

I'm pretty sure the motor isn't a Meccano item, and Frances could well be right about it being WW2 surplus.

The green plate has been made from a fire-extinguisher label or perhaps a fire control lever from a console. The engraved letters probably spell out:

IN CASE OF FIRE
TURN HANDLE TO LEFT AND
PULL TO FULLEST EXTENT

For some reason thie instructions remind me of aircraft engines?

The two knurled brass terminals on top were common electrical items and I guess got used because BA screws were handy to the maker. The lower screw also appears to be BA. They're not Meccano threads. The gears and collars are genuine Meccano as Howard says.

As parts have been painted Meccano Red and Green, and the two support strips ave been rounded to resemble Meccano parts, and because the output shaft is Meccano size, I think this was put together by a serious Meccano modeller to drive something big. It could have been made yesterday, but the colours and motor construction make 1955 more likely.

Dave

My father in law got one of these mechanical computer bomb sight mechanisms in the 1950s from a war surplus shop in Derby [Potts] if there is anyone on here is familiar with the town and that famous 'magnet'

It finally came into my possession when we got married and I can confirm that the internal fittings were all made in the USA, I found markings on parts of it that named a well known organisation, possibly Sperry based in Chicago, who I believe also made navigation gyroscopes .

The quality of all that material was quite superb and a world away from Binns output for Meccano

Shaft trunnions were dowelled to the frame for example and a lot of space was taken up with very nicely made metal bellows for altitude determination.

Brian.