The BSA A7-A10 Forum

Technical (Descriptive Topic Titles - Stay on Topic) => Lucas, Ignition, Charging, Electrical => Topic started by: Tumbleweed on 03.10. 2017 11:59

Title: insulating washers
Post by: Tumbleweed on 03.10. 2017 11:59
hi everyone , can any one tell me how the washers fit ,  my new set didn't have any washers ,   steel points later mag I think 1959 a10 ,   thanks
Title: Re: insulating washers
Post by: groily on 03.10. 2017 13:20
Have a look here, at the Lucas supplement for the later steel cb assembly where there's a good exploded view: http://www.brightsparkmagnetos.com/library/LWImags/Motor%20cycle%20rotating%20armature%20magnetos,%20Sec%20L-5,%20Pt%20A,%20supp.pdf
Should be reasonably clear I think.
Key things are not to let the spring blade on the opening point kiss the camring at any point, as it is 'live'; to ensure there's an insulated washer on the pivot post under the opening point so the metal bits of it can't touch the backplate; that the 'figure of eight' insulator is correctly sitting on the backplate between it and the fixed point's bit of bent plate; and that the screw that retains the fixed point mount to the backplate has an insulator under its head (unless you're fitting an easycap capacitor, when you don't want that one).
Title: Re: insulating washers
Post by: Tumbleweed on 03.10. 2017 13:39
 Thanks Groily ,  so fig 4, 8 , and 12  are insulating washers ?
Title: Re: insulating washers
Post by: JulianS on 03.10. 2017 16:50
12 are hard fibre of different thicknesses used to align the contacts.

Photo shows what lucas supplied as a set of points, showing washers 4 and 12. Shame pattern points do not come with all the parts needed!
Title: Re: insulating washers
Post by: groily on 03.10. 2017 17:59
Yes to fibre for alignment purposes and Yes to Shame about.  Fften original bits are undamaged - but note point made in the pdf about the retainers.
Those retaining clip wotsits can be had from various suppliers (though the overall diameter of some versions can get in the way of a spanner on the centre screw in some cases).
Why isn't anything ever as easy as it orter be  . . .??
Title: Re: insulating washers
Post by: Tumbleweed on 03.10. 2017 18:12
these are hard to find washers  and critical I suppose , the plumbers dept  in the store will have them . thanks for your help   .  t w