Second request : what is best way to clean brush after use????

use a vacuum or take it out and shake it.

I used the attachment on my vacuum and it worked great

In the sink with detergent, then air dry!

I found that running the brush under water works best in getting the dust off.

using a vacuum cleaner

I plan to take it outside in better weather and point the high stream of the hose at it

I'd probably rinse it under the sink then air dry. That's what I plan on doing. Since the bristles are hard, I don't see that damaging anything.

Rinse with water and then let it air dry.

the easiest way to clean it is to run it under hot water and shake it it will make it look like new again

You can lightly tap the dust off the brush.