Speeds and feeds deep drilling

[Jonathan]

Thanks fellas turning the amps may have helped?

Until the iron saturates, torque is proportional to current, so yes it's likely to help. Keep an eye on the motor temperature though - no more than 80°C on the case is allowed. Do you have the model number of the motors so we can check what current they should be run on? Iff the motors, drivers and power supply are safe operating from 3.5A you might as well put them all on that current and get better feedrates or reliability.

[m_c]

Taking a decent cut of metal will of made a big difference.
If you don't take a deep enough cut, the heat builds up at the tip, leading to work hardening, and chip build up on the drill, which then reduces cutting effiency further.

It's best to look at the speeds/feeds for what you're using, and work out what the limiting factor of your machine is. Mostly in aluminium, spindle speed is the limiting factor.

[Razorab]

These are the motors Xylotex Stepper Motors I think as I bought it of a guy that split his cnc machine, motors and controller, ball screws and nuts, x2 mill, no idea whey said he got more for the parts than compleat. There's no label on the motors.
Speed of the spindle does that affect quality of cut or speed of cut.

[m_c]

Just speed of cut.

I just ran through some figures, and for a standard polished HSS drill suitable for soft alu, gives aprox. 2500-3100rpm.
The recommended feed rate is 0.19mm per rev, which equates to 475 to 590mm/min feed rate.

To acheive those feed rates, requires 450N of thrust and a 0.25kw spindle, and that's with a sharp split point drill. With a dull standard point drill, those figures rise to nearly 700N and 0.33kw.

However all those are theoretical, and just provide a best case to start from. Experience and experimentation on your particular machine will find the best for you.