I can’t imagine that this was done accidentally, can’t even call it damage because the pump has a very prettily decorated nut. The design? is quite even and there are no rough edges. How or why would someone want to do this, any ideas?
Because they were an ignoramus... I'm now wondering if someone with a lathe and knurling (or whatever) tool could restore that...
The wear looks to have some age to it and it would certainly take a number of years to inflict that kind of damage, presume from the use of mechanical grips or plyers? It could be re-knurled on a lathe with a knurling tool but time and cost (if you cant do it yourself) would probably out way the value of the pump.
What's the name of the tool that would recut that to match the other parts of the pump top? It's not actually knurling which produces a cross-hatched pattern. Maybe it's called 'straight knurling' or something. Where's Ray (Longilily) when you need him? Sorry to be dumb but my last formal metalworking was done as a 6th form minority-time subject well over 50 years ago now...
I'm not sure @David Shouksmith I only know it is a knurling tool, in essence its a pair of cut gears that come together, in opposite directions to create the cross hatch effect.
Linear knurling tools exist. You may be able to just buy replacement cutters for an existing tool. Repair depends on having enough metal left over once you have removed the snot. I suspect the original damage caused by repeated use of grips rather than changing the seal....
Not to worry, I have more spare pumps than I know what to do with. I hate to say it but i quite like this odd one. No grip to it of course.
