I have a ball that is currently at 4000 grit and would like to change the surface to 2000 grit. I have a ball spinner and abralon pads, and was wondering what the correct technique would be to alter the surface? Can I just use a 2000 pad, or do I need to take the surface to a much lower grit (e.g. 500) and then use a 2000 pad? Thanks.
If the ball/surface is at 500/1000/2000/4000 grit, then, yes, just taking a fresh 2000 grit to it, dampened, and by hand, you can take it to 2000 grit.
If the ball is at 500/4000 grit, then just be aware that by taking a 2000 grit to it, it is now at 500/2000 grit. That is different from 500/1000/2000 grit.
The ball is currently at 500/4000. The final surface that I want is 500/2000, so going directly to 2000 sounds like the right approach. Why would it make sense to alter the surface by hand rather than using the ball spinner? Wouldn't the ball spinner produce a more consistent finish?
Spinners have a tendency to take the surface to a slightly higher grit than when you do it by hand. Many abrasives these day shave a sponge like backing that both makes it easy for the abrasive to conform to your hand and the ball and they hold water which helps keeps down dust and lubricate the abrasive.
Almost all the time it's best to do the final abrasive or grit level by hand for "grit accuracy".
Thanks, this is really helpful. I'll just use a 2000 pad by hand to alter the surface. Is there a best practice on the technique on how to do it by hand? My initial thought is to use a wet pad and do all 6 sides (5 seconds per side) using light pressure. Thoughts?
6 sides may be overkill and may take it to a higher grit too easily, even with light pressure. Try 4 sides at first and see what it gets you.
I almost always put the ball in the spinner's cup and use circular motion, with dampened pad, pushing it from front bottom (6:00, as you look at the ball from the top/above) at the cup's edge, towards to side to about 2:00 (looking down on the top of the ball, sliding up towards the top of the ball. Then repeat. Pushing the pad towards that 2:00 position, where the ball surface meets the edge of the cup, will push the ball slightly counterclockwise, while you are rubbing it. Turn the ball over 180 degrees to do the part covered by the cup. Then rotate 90 degrees to do the "third" side; then another 90 degrees to do the "4th" side.