Rigid tapping- first real one!

[cncdrive]

The UC ethernet controllers can read about 100kHz max. frequency, but e.g. the -5LPT motherboard limits it to about 50kHz.
With a 100CPR (400PPR) encoder the 50kHz is at 7500 RPM.

[Battwell]

i set the encoder output from the drive to 2500 counts
it works ok and reads speeds fine up to my maximum of 5000 rpm
i wont be tapping that fast!

originally i had encoder input to uc300eth at 10000 counts but the speed reading would be wrong above 2400 rpm. so i divided the output by 4.
the servo spindle ive ftted is only 1kw. so thats my limiting factor. was the most powerful i could find with an 80mm frame (biggest i could wedge into the existing casting)
tonight i will test at what the "merican machinists" have advised 600 rpm in steel and 750 rpm in aluminium.
watch out for an epic fail video

[Battwell]

i asked on machinist group yesterday. the figures i quoted were maximum recommended speeds for m6 size tap ( a few of the guys showed book figures for top quality taps they use)
show me some real life figures or succesful video- and il try it

[Battwell]

600 rpm
https://youtu.be/W6WEeV5rPSw

[Battwell]

At 1200 rpm I had to raise the start height to 5mm above work
I think that’s fast enough for an old mini mill
https://youtu.be/mhANVN6tvCI

[ger21]

Compare that to your first video, lol. It's at least 100 times faster.

[Battwell]

Yup- I was amazed the tap took it!
Never worked with metals- I'm a wood guy!
Wouldn't even have risked my machine trying this with Mach.
Uccnc - winner!
Videos on utube. I'm sure cncdrive will get a few more sales from them

[Battwell]

spindle drive is tuned very tightly for position control. its running step/direction
i loosened the acceleration control in uccnc a fair bit when i was testing as i hadnt put m5 in before m30 - which was stopping the spindle dead (and at 3000 rpm+ that would cause bus over voltage) now with m5 it decelerates over 1 second so is fine.
now ive realised what was causing it- i can make spindle step/deceleration tighter again.
my first test at 1200 rpm- it didnt decelerate quite enough- and the collet nut caught the test piece
its been a fun test .
i can run the drive off c axis- tested with same outputs before. (will do this as and when i need it)
next job is my arduino modbus control panel- as ive run out of inputs on uccb.

[Battwell]

my pc- is right behind the panel area- so ideal just to plug it into the usb port with a short cable.
ive had 1 of the arduinos permanaently connected to my office pc for a year- runs any time uccnc is connected.
set up at the moment as 16 inputs, 48 outputs plus 8 analog in and 8 out. (mega)
should be enough.lol
(ive used 3 full ports on the mill so far. )
none of the buttons will be time critical. modbus is looped at 100ms.

here it is- when i first set up 2 megas with uccnc

https://www.youtube.com/watch?v=7-T4hNrYVa4