Power tapping test results

[Highpower]

(03-29-2015, 08:03 AM)PixMan Wrote: Ed,

You shouldn't have any fears about power tapping, as long as your spindle reverses in a reasonable way. Some VFD's need tuning to get them to reverse the way a 3-phase motor on true 3-phase power does.

I have discovered that can work against you sometimes too. My mill runs off of a 3HP rotary phase converter and is as close to 'true 3-phase' as I am ever going to get. I was drilling some holes on my mill one day and did an accidental 'plug stop'. (Switching from forward rotation to reverse rotation instantly.) I overshot the center OFF position on the power switch.

You know how keyless drill chucks self-tighten when they spin forward? I found out they self-loosen too, when suddenly spun backwards. The drill bit fell out on the table!