bugbear":1xj2c7bq said:If you don't want to pay for a grinding surface, you could buy one of the clip on abrasive gadgets.
They're far more effective than back lapping with loose SiC paste.
This sort of thing
You need to fit them with lots of clearance and then VERY GRADUALLY do spin/tighten cycles, until the blades have been ground over their entire surface.
This took around 10 minutes on a fairly blunt Qualcast Concord; I don't know how long it would take on your machine.
EDIT; old (generally favourable) thread on these gadgets
https://www.ukworkshop.co.uk/forums/shar ... 24542.html
BugBear
220 grit or 120 grit SIC paste, tighten the cylinder to the reel and run the reel (backwards) with a cordless drill. It takes about a minute to remove major wear with back lapping. if you spin the reel by hand, then certainly that'll take a long time, but it's not something I'd do if you can get to the drive system and get a drill on an axle somewhere.
If necessary, the operation can be done twice. Once the paste is broken down, the mower is already in adjustment at the end of the sharpening cycle with uniform contact.
If it's well adjusted, it will cut light and heavy grass only a little bit differently. If it's too loose, it'll cut easily in light grass and be very difficult in heavier grass.