ATC Options?

[andy_con]

Thanks for the link, interesting kit but I need the spindle as well, it seems easy in the 0 to 6000 rpm range but i'm in the 6000-24000 rpm range and then things get ££££ really quickly.

but that's the point of that powered draw bar, fit whatever spindle motor you want. providing the actual spindle it belt drive that powered draw bar will work

[Davek0974]

Issues i see there...

Not sure a belt will work at 24,000rpm,
The spindles suitable for ATC use are all rated to 6000rpm only it seems, that means special bearings and balancing would be needed for that sort of speed.

[komatias]

Andy, That PDB has an impact wrench and a pneumatic actuator inside so is only suitable for screw in drawbars. For ATC at 24000, you need a totally different direct drive spindle such as those seen on Alibaba.
They should be balanced but I dare say that the tooling you get will not be.

[andy_con]

im well aware how that drawbar I posted operates, the original post said cheap so I was just posting a cheap option.

[Davek0974]

No worries here ;) thanks for the thought.

It does seem that it's a non-starter at present due to the spindle speed I have.

I am now looking towards a bigger machine, maybe converting my Bridgeport or finding a donor with duff electrics that was built for CNC.

[andy_con]

do you need such a high spindle speed?just think a large machine like a haas has an 8-10k spindle speed with bucket loads of torque and that can cut fast and deep. its not all about spindle speed but machine strength and torque. so could you get away with a slower but more powerful spindle?

[Davek0974]

Possibly, but this was built for small cutters in aluminium, small cutters are best in carbide, carbide likes high speeds, sort of horses-for-courses really.

I am sure my stuff can be done in HSS but not calculated the feeds, I will have a look.

Engraving really does need speed I think though??

[Davek0974]

Interesting,

Just calculated the speeds for a 2mm cutter in 6061T6 and it seems I am seriously under-using carbide anyway.

In Carbide, at full speed it needs 82,000rpm, HSS wants 23,000rpm

The reason I had not seen the high speed before was because I limited HSMAdvisor to calculate feeds based on my limit of 24,000rpm, removing this limit shows the full feed & speeds.

Anyone got an 82,000rpm spindle? :)

Anyway, HSS will do the job at say 6000rpm but it will be much slower.

[Davek0974]

Should that be "Unless your'e using large tools" there Jazz?? :)

[JAZZCNC]

do you need such a high spindle speed?just think a large machine like a haas has an 8-10k spindle speed with bucket loads of torque and that can cut fast and deep. its not all about spindle speed but machine strength and torque. so could you get away with a slower but more powerful spindle?

Unless your using small tools then speed is required.!! . . . This is small light duty machine who's main operation will be with small tooling requiring high speeds 10K minimum.