Random Orbit sanders

[bkim]

I'm prepping my bass for oiling. I've seen people mention using random orbit sanders.

At what point (or grit) can you stop sanding with the grain and begin to use the ROS?

Its an Alder body with Quilted maple top.

[FBB Custom]

The ROS is magical. All flat surfaces I start with the ROS at 150 grit, then 220. I then do all surfaces by hand to 320 and wet sanding 400-600 (also by hand).

[Geoff St. Germaine]

I use a ROS and it is great. At higher grits it can leave noticeable swirls, but once you get reasonably high they are pretty much gone. Then I got to sanding with a block with the higher grit paper. It's really good at getting out high spots quickly without having to use a lot of elbow grease.

[Musiclogic]

on bare wood, stop at 220, switch to ROS with 220, then 320, and 400. block sand with 600 and 800 to get the final smoothing, and start the oil.

[Suburban]

I haven't used the ROS for my basses, though I have one.
Reason 1: It has a nasty habit of eating into vertical surfaces if you get too close, e.g. into the fingerboard when sanding the body top.
Reason 2: It only works good on flat surfaces, and my flat surfaces are small.
Reason 3: I do pretty small bodies, anyway...

I know that somebody found a sponge inset to put between the sander and the shett. This would make it possible to sand curved surfaces. If I find such an item, I will reconsider my use of the ROS.