by shane »
Thu Mar 15, 2007 10:12 pm
Kind of sounds like the centre of the main spring is broken or slipping to me.
But like Roger says, take the motor board out and have a look at it. If there are no visable signs of damage on the gears, wind it up while your watching the motor, and if you cant see anything slipping-it'll be the mainspring.
Usually if a spring is broken on the outer coils, you'll be able to wind it a few revolutions before it slips, but a break in the inner coils will slip straight away.
The later HMV springs were held onto the centre arbor by a "V" shape in the spring,(like in the picture below) which slotted into the arbor. Early ones, and most other brands, used a rivet protruding from the centre arbor, with a pear shaped hole in the spring to secure it. The outer coil would be held to the barrel this way.
If the spring doesn't look broken, the "V" might have stretched out of shape. You may be able to heat this "V" shape, and squeeze it back into shape with a pair of pliers. The main cause for it getting out of shape is people spinning the turntable backwards! If the centre is broken, you'll be needing a new spring. Breakage on the outer coil is much easier to fix. If it turns out to be the spring, let us know, and we can tell you a safe way to remove the spring from the barrel, because you'll need to remove it before doing any repairs.
