Help - can?t identify what?s scraping

[Bigbaldybloke]

Another option would be to take the spring off and purposely grind the bottom end coil so that it is not square and tilts the spring to one side. It would only be a small amount and you would have to ensure the spring is installed the right way round and does not rotate over time when in use.

[sabbot]

Thanks ?bigbaldybloke? - I like that idea but rather than modify the spring I?ll shave a fraction off one side of the upper lock ring for the adjustable spring seat. That way I can lock the low side of the ring in one position.
Thanks again to everybody who commented I make the modifications at the weekend and hopefully be able to report a quite disk by Monday.
P.s. sorry about the previous repeat pictures - it took me a while to figure out how to post them. But now that I have I?ll add one of the most recent use for a 3D printer.