cleaning/tidying up layshaft threads

[Scooterslag]

Got a pretty decent condition Innocenti layshaft which I intend to use on a engine rebuild, only problem is that the threads have been knocked (not too bad I might add) and could do with a clean up with a thread file, I know layshafts are one of those things that must be in perfect condition so would this be ok and what size thread file would you recommend? oh theres a small amount of surface rust on the thread end as well (bearing faces are perfect) thanks Paul

[gaz_powell]

its difficult to tell the condition but if you are happy with it just run a thread file over the threads or a die nut, my thread file has various pitches/gauges so you get the right one

The thread is 16mm x 1.5mm pitch

[Tractorman]

A thread file is fine but you could use a small triangular file to clean up the threads.

[Warkton Tornado No.1]

Cut an old M16 x 1.5 nut almost in half (same pitch as engine bolt) then spring it open a bit.

Wind it on & clamp not too tightly in a vice on to lay-shaft thread @ spline end with grinding paste between.

Wind the lay-shaft out & in a few times, gradually tightening the grip & you’ll tidy the thread up no end.

Be sure to remove every trace of paste using somebody else's toothbrush...

[MK Monty]

When I was in to scooters the first time round and the only tools you had was a hammer and some old bed spanners, I mullered my hub threads. Not knowing how to get the nut on my 85 yr old grandad ex loco shed man said lets have a look. He got the nut and tapped it with a hammer, turned it tapped it again and worked it on a bit at a time. I was amaised that this old guy had the skill to get it sorted. Yours looks fine

[Scooterslag]

Cheers for the replies fella's

[rossclark]

The threads are very hard. I ruined a thread file trying to clean up some dodgy layshaft threads.