If I have a 6" do I need a 5" ROS?

[Brian Burns VT]

Point taken. I was still looking from the OP perspective of low-end 5" sander. I think all of this math is totally dependent on usage, current compressor set-up, dust mitigation needs, ergonomics etc. and I think that a lot of people haven't used dynabrades and don't know just how comfortable they are compared to some other, corded options out there. I've used the new Mirka and Festool sanders and like them but would always choose a dynabrade over them if I were sanding stuff that required sander agility

[Rich Engelhardt]

If OP doesn't have the compressor set up to run one, it's a moot point but, in a perfect world, they should be strongly considered for any shop.

At this stage of my life, I'm not really going to get a larger compressor. MY little Ingersoll Rand 2.5HP Twin Hot Dog - won't support an air sander.

This is strictly an electric (or battery) tool.

[Mark Bolton]

Point taken. I was still looking from the OP perspective of low-end 5" sander. I think all of this math is totally dependent on usage, current compressor set-up, dust mitigation needs, ergonomics etc. and I think that a lot of people haven't used dynabrades and don't know just how comfortable they are compared to some other, corded options out there. I've used the new Mirka and Festool sanders and like them but would always choose a dynabrade over them if I were sanding stuff that required sander agility

Agree'd on all points. Threads evolve. Look into the AirVantage or Surfprep with the separate transformer. Identical envelope of a dynabrade (why I like them) and a mere fraction of the operating cost with great dust pickup. Put the money in your kids college fund.

[Brian Burns VT]

Perfect. Stick with the 6" and disregard the previous handful of posts!

[Randy Heinemann]

I find that I use my 5" Festool sander for smaller jobs. Plus, with the new ETS models, you can get an edge sanding guide. For me, the guide yielded amazing results with almost no learning curve. Just for that alone, it's worth it to have the Festool 5".

[John K Jordan]

I...
Since I have the 6" Ridgid - which is a really great tool - do I need a 5" ROS too?

I doubt it but depending on what you do you might make good use of an even small ROS. I use a 3" pneumatic palm sander and a 2"/1" Grex pneumatic ROS. These are perfect for small things and curved things like some wood turnings. What I like most is I can run them at very low speeds with fine paper so the effect is much like hand sanding. These might not be as useful for large flatwork. They are extremely light weight since there is no electric motor.

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