Thornton Pickard shutter spring

I have just started to unpick the first of three recently acquired TP shutters, and found that the shutter barrel that contains the coiled spring in non-functional.
That is to say the central rod can spin round inside the outer barrel with freedom.
A careful inspection of the surface of the brass barrel shows what two small holes about 1/8" apart, which I assume might have been the location of one end of the spring.
The central rod traps the top plate with a knurled knob at the top (and about 0.5mm freedom of movement), and the bottom is closed by a brass 'washer' inside the barrel.

I could add more details, but my question is does anyone know how to get the thing apart ?

The bottom edge of the barrel does seem to have a very slight burr on it, but I don't want to use any excess force until I know how it is built.
My bottom line is to take it to my friendly dentist, and pay for an xray !

John

Some slight progress.
I've discovered that the knurled knob unscrews(with some persuasion) from the central rod, and allows me to remove the top plate.
What I'm now faced with is the outer barrel has 'washers' at each end, held in place by this tiny burr. I've started to remove one with the aid of a scalpel blade, and I'm hopeful this will allow the central assembly to slide out.

John

Success !

The 'washer' turns out to be about 2mm thick, but once the last trace of the burr was removed, a couple of taps on the knurled knob end, and the whole thing slid out, much to my great relief.

I now realise that I'm going to need the other end open as well, so that I can re-position the top turn of the coil out through the tiny holes in the side of the barrel, and that will be fun !

EDIT 15 mins removing the burr, and the second washer/bush is now out, and I can go to bed, leaving the fiddle of the rebuild for tomorrow.
Night all,
John

Those burs are called "stake". Staking was the means by which fasteners were secured so that they did not come out. Burnishing with a file is the best way to remove the stake. Use a punch and mallet to stake fasteners but that barrel may require the use of pliers.

I have saved 1 TP shutter form destruction, it needed the curtain patched.

Hi shutterfinger, and thanks for that bit of info. Love coming across other meanings to common words. What a rich language we share.

The shutter barrel is now cleaned and re-assembled. Bending the last coil of the spring so that it was at right angles to the surface of the barrel allowed me to line it up with one of the small holes, so that as I carefully pushed the central rod plus spring down into the barrel, the end of the coil popped out through the hole. Sounds easy, and it actually only took three goes to get it to work !

Onwards and upwards,
John