4.3 mm holes, 20 mm deep

[Chaz]

Hi Chaz,

If it helps - in the line boring video I posted recently you can see 3 mm holes being peck drilled (with full retract to clear the chip) at ~12,000 rpm. Can't remember the feed - maybe 300 mm/min? Drill bit is plain HSS.

You can see the chip fly out each time, and a dab of oil keeps it running smoothly. Starts at 0:32
https://www.youtube.com/watch?v=sYhDtuqzf2I&t=6s

Been using this method for some time and it works well.

Thanks.

I did some checking last night. My VFD's current looks to be set correctly.

There is an auto compensation value for increased torque demand. Set to default of 2% but can go to 10%. That's now changed.

There are also some parameter values between PD005 and PD010 which allow different torque curves. I *think* default is a constant curve, there is an option to go for what's called high torque where it provides better torque at lower speeds. This will help a bit, Ill lower the speed and see. Clearly the feedrate of what I was doing was too slow too.

Also, what oil do people use? Anything specific or just 2 in 1 oil? Ive got big container of VG220 Mobil oil that I got with one of my ballscrew / rail orders. Would that work and is it better than trying to spray WD40?