Hopefully, you are only using steel bristle brushes on cast iron blocks. Those would grind away aluminum blocks while leaving LOTS of aluminum shavings in the block.
Absolutely fine. (all of us gunsmiths went bug-eyed when he described machining his SS rods to accept 'soldered brushes' ... eeekkkkk!! Bore brushes are made in many cool sizes .. in many materials and grades ... WITH threaded bases for quick inter-change... MUCH quicker and cheaper than MAKING the brush/rod combos he's describing...) We spin them with drill motors all the time with good results ... so do it!
Yep, you can use gun cleaning kits by hand But the brushes need to be high quality to not get waisted immediately by a drill motor, so there is a reason he is showing how to make one strong enough to use on a drill fyi
His brushes are hardly stronger than the average or better quality bore brushes. We spin them on drill motors all the time. (Just have to spin the correct way to avoid unscrewing the threaded sections ...)
