Micro Scratches after fret polishing?

I have a couple of levelling beams. One is long and does the initial levelling with 120 grit. I use belts for a belt sander- very consistent and tough. I use that to get the frets close. I then switch to a smaller beam with 320 on it to finish things off. I then crown with a diamond 300 grit file. Once left with that thin line on top of the fret, I go side to side with 320 grit or sometimes 180 to start. Then 400, 600, 0000 wool, buffer. That's it.

The key here is your own strength to make sure each grit does its job fully. It's easy to move on before each grit has done its job.

 

I like steel wool, too. Easy final polishing. Removes a lot of material and your thumb follows the fret shape leaving a rounded surface.

Just beware, if you're doing an electric, the shavings will be attracted to your pickups. Bag them or mask that area.

 

I wouldnt use steel wool...if any gets in your pickups they will conk out on you...might take a day...might take a month...but die they will....once that stuff starts to rust it will degrade your wire ...and it can find its way into your pots and switches too
i make jewelry out of copper and brass...and cuprinickel
for polishing i do it all by hand...same as for frets...they dont need to shine like the crown jewels by the way...
cover everything that isnt getting polished..its a mucky orrible job...(i love polishing metal....)
try using the finest wet n dry paper you can find....then use brasso or a wadding polish.
i worked in heavy lifting gear for years...my hands alone can shine up anything softer than hard bronze.
keep shining a torch along your work...that way you see your results better. patience is your watchword here.
fretwire for most part is a copper/nickel alloy...quite a soft metal...depending on nickel/copper ratio

 

Yep, it seems like you aren't staying on grits ling enough to fully get the previous grits' scratches out. It can be very hard to see, but becomes much more apparent when things get all polished up. Maybe try alternating or moving around your light source to get a better eye on your work, and if you don't already have them, a magnifying visor and a jewelers loupe are a great help at not that much cost.

 

I like the results I get with steel wool in the late stages of fret-polishing. I tape off the pickups first; I actually put some tape sticky side up over the magnets to be extra sure.

If it's too late to take precautions like that and bits of steel wool do get into the pickup cavities, it can be hard to get that stuff out, but you have to make an effort. Canned air, a vacuum cleaner with a very fine attachment, tape, a magnet not strong enough to damage the pickup, whatever.

 

I would worry more about the metal filings from fret levelling more than the steel wool. I've run my own repair shop for over 10 years and have yet to have any damage reported from steel wool use. I tape over the pickups and over switches etc. I also clean up after. Nothing to worry about.

 

i wrap everything too..only bit exposed is what i need to work on.
we all find our own ways of doing things...hence its good to swap ideas and maybe find different ways....2 heads better than one...my worry about steel wool is a magnetic b it rusts and as it rusts it swells and can destroy pots and pickups as it does so...it swells as it oxidizes...and the flippin splinters you get...often only found when you stretch to nice chord and ...oooyah......been doing guitar work for over 40 years....i learned from the guy that did pickups for Burns and was chris reas guitar tech for years....man called Jim Cairns ...sadly no longer with us.
a set of his pickups are in my jazzmaster...theyre the dogs danglers too...wouldnt want anything nasty to get inside those
i ve never used a file yet...whetstone and fine wet n dry and polish...but never a file...unless im making a new nut....and enen then i sand it to shape and size by hand...only power tools i own is a sander and a drill...only needed to use drill on guitars rarely

 

Meguiar's Ultimate compound is what I use. Am I too old school?

 

I use the little micro-fiber pads that go up to 12,000-grit. No micro scratches that a human eye can see. Available at StewMac.