Listen to this: Spindle Squealing on Vimeo This is my water cooled 1.5KW, 110V spindle. It's cutting air over a jig. The same short program, run twice. Hear the squealing in the first run? It started doing that not long after I started using it. Back then it was occasional and fairly quiet. Now, it's frequent and loud. I'm trying to get support from the vendor & they're telling me that the spindle manufacturer says it's normal. Do any of you think that is normal?
I'll throw my vote in for busted bearings... If the seller doesn't want to honour warranty - consider Aliexpress/ebay dispute - but likely they have a "you ship it back at your cost for service" loophole too If you have access to a press - replacing the bearings shouldn't be too hard (nor expensive) and you can install decent quality ones in their place 13.65US $ 9% OFF|800w 1.5kw 2.2kw 3.0kw 3.5kw 4.5kw 5.5kw 6.0kw spindle bearings 7000 / 7002 / 7004 / 7005 / 7007 / 7008 7 series bearings|Woodworking Machinery Parts| - AliExpress