[ardenum2]

take a look at a zkln bearing, which is a double bearing, no preload issues or a fk support that has 2 matched bearings.

[binfordw]

The zkln's are a bit pricey for this setup, I ordered a set of BK12 mount and a BF12 support, I'll fit those on and see how things go.

I may try to replace the X and Y mounts with similar, it looks like the "kit" I bought years back just replaced the leadscrews, and used the original bearings.

[binfordw]

Well holy crap.

I installed a cheap Z ballscrew mount with angular bearings today, and put everything back together.

I did a couple test cuts in 6061, and it sounded fine. I loaded a program for a part I was wanting to make, and it ran like a champ.

I tested a plunge cut with an 8mm 5(!) flute endmill, because its what I have a boatload of, and it plunged better than I could have imagined- 8ipm feed and it plunged without drama! I've NEVER been able to plunge an endmill at more than 1-2ipm without things going bad


I did op 2 on the 6061 part I had, which was pocketed counterbores, again, 1000% better than ever. I manually centerdrilled the through holes, and ran a drill through them at 15ipm and it was solid!


I can't believe I've had this mill for nearly 15 years and have been too stupid to realize the Z ballscrew was walking back and forth was causing the poor performance. I'm super excited to see such great plunge cut performance!!- Cut performance in general!!

[joeavaerage]

Hi,
kool. On the basis that its working at is supposed to....do you still feel the need to upgrade?

I would guess that if the machine performance is limited by virtue of it flexing...then ultimately the machine is just not stiff enough, and no amount of fiddling around
is going to materially change that. If however you now estimate that the machine IS NOT flex limited then upgrades like ballscrews/steppers/linear rails etc all make sense.

Craig

[binfordw]

From my initial cuts, the mill is well worth upgrading now. The mill sounds solid, and the surface finish is far better than ever before.

I'll probably tram it and check for backlash in the XY over the long weekend.

Super happy. Can't believe I missed this "minor" detail of the ballscrew mount.