Spindle bearings and chatter

Hey all. I have just built my own CNC lathe from a Warco lathe. Works great BUT, I am getting alot of chatter when turning steel. I have made sure all tools are tight, new spindle bearings, no play in slides, all new ball screws. I have read that the spindle bearings may not be up to scratch. I was wondering what people have used when they have built their own lathes from scratch. Please help as its starting to ruin the fun of building this machine. Cheers

Not a warco but I did see a dramatic improvement on my 7x14 mini lathe by doing the following.
1: Removed the compound slide and made a solid tool-post riser to take up the height from the missing compound slide.
2: Replaced the spindle roller bearings with taper roller bearings (angular contact bearings may be an option). Which ever may you go check the speed ratings just to be sure.
3: Lapping the cross slide dovetails can help (no need to go whole hog and scrape them) to reduce rock, don't rely on the gibs to do this.

Below is a good article on prepping a mini lathe, although not the same as a warco, it is a good read and may give some tips on checking the saddle & cross slide fit.
www.toolsandmods.com/library/marty-nissen-project-lathe
Try to reduce any tight spots that maybe found when pushing the saddle across the bed.

I also discovered that having 2 microsteps is FAR worse than 16. I set it up to having 16 microsteps instead of 2 and motors much quieter and also 96% chatter has gone. I will look into what you suggested. Many thanks.