In defence of mag restorers everywhere! I thought I'd throw in a bit of information about the points centre screw. Obviously it does need to be tight enough to hold the points in place but........ the threaded part of the screw screws into the primary windings connection from the ignition coil. This connection is essentially a square nut insulated from the armature body by a piece of flat fibre material (a bit like the material fibre washers are made from). The square nut is prevented from spinning by its location in a square hole in a plastic insulator tube. If the screw is overtightened two things can happen, 1) the square nut can punch a hole in the fibre insulator and make contact with the armature body, or 2) the square nut can burst the shoulders off the plastic insulator tube. Provided the mag restorer has done a good job with the armature and bearings most other matters are within the scope of most owners. The aforementioned problems are often caused by the plastic insulator tube being manufactured a little too short thereby allowing the nut to travel too far before it tightens, by which time it has guillotined the fibre insulator. The plastic insulator tubes don't seem to be available anywhere so I make my own, to the correct length, and I supply some of the other magneto restorers with them. So, tightening the points centre screw is a slightly more delicate operation than many realise - I have come across plenty of mags where the overtightening of the screw is what has stopped the mag. I can understand why a mag restorer (and I honestly don't think it was me!) might be a bit cautious because, if the screw is overtightened and the fibre insulator is chopped, the mag and the armature have to be dismantled to fix the problem.
