Hi everyone, have anybody installed and run a 3.0 Kw spindle and VFD?, powerfull enough to mill aluminum?.
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Hi everyone, have anybody installed and run a 3.0 Kw spindle and VFD?, powerfull enough to mill aluminum?.
Hi,
it depends on the size of the tool and the chipload.
If you spindle is a highspeed/low torque spindle as is common then then toolsize will be limited by the torque.
For example:
power= torque x speed
speed =24000 (rpm) x 2 x PI /60
=2513 rad/sec
torque= 3000 (Watts)/ 2513
=1.1Nm
It will not take a great deal to stall a spindle with only 1.2Nm of torque. You'd probably be limited to tools 8mm diameter or less.
Imagine however if you have a 3kW AC servo as a spindle motor with rated speed of 3000rpm:
torque = 3000 /(3000 x 2 x PI /60)
=9.5 Nm
Now your talking, you could spin a 20mm or 25mm tool with that sort of torque.
Craig
Yes with 3Kw 4 Hp it will do quite well for milling aluminum there are a lot that use 2.2Kw spindles for milling aluminumQuote:
Originally Posted by Al321
Everything will depend on the quality of the spindle you get as well a 3Kw should have a amperage rating of around 10 amp to 12Amps so if the spec's don't give you this then keep looking
The 2.2Kw spindle have a amp rating from 8 Amp to 10 Amp range
You can also get a 4 Pole spindle
This is one of the better low cost spindles 3.2Kw 15Amp and you can have ceramic Bearing for an extra cost
https://www.aliexpress.com/item/1005...626517271EfteM
Just asking if a 3kw spindle is enough to mill aluminum is not enough info to get a useful answer.
Almost any spindle can mill aluminum if the tool and cut is small and light enough. Or if it's just for hobby work where speed is not important.
If you plan to use 1" end mills for slotting, it's the wrong spindle for the job.
If you download GWizard you can use the free trial period to look at how much power, speed and torque is required for a specific width and depth of cut in each material. It's useful for getting a little context and perspective when deciding how much power you actually need.
Also, "3kw" doesn't tell you how much torque a spindle has on it's own. You'd need to know the speed where it reaches peak power.
This 2.2kw spindle peaks at 6000rpm
https://www.damencnc.com/en/quicktoo...rpm/a3969?c=22
and has more low speed torque than their 6kw model which peaks at 18,000rpm:
https://www.damencnc.com/en/quicktoo...rpm/a2806?c=22
In general though, if you have sensible expectations on end mill size and depth of cut you'll probably be able to make aluminum parts with a 3kw 12,000-24,000 rpm spindle.
I've been using these 1/4" ZRN coated carbide end mills with good results at 20,000rpm+:
https://www.ebay.com/itm/15302213203...Cclp%3A2334524
I recommend getting a water cooled model and mist coolant as cutting aluminum at high rpm generates a lot of heat.
Hi,
I use flood coolant, and it makes a huge difference.Quote:
I recommend getting a water cooled model and mist coolant as cutting aluminum at high rpm generates a lot of heat.
Built-Up-Edge (BUE) is a major problem when milling aluminum. The aluminum chips 'weld' themselves to the tool, the tool loads up and stalls (if low torque spindle)
or just plain breaks. Excessive heat is the usual cause. You can slow the spindle, it will help. Cooling, either flood or mist will also help, and it's less to do with cooling but rather
flushing or blowing the chips out of the cutzone. Re-cutting chips is a prime reason for BUE.
Most carbide coatings are TiN, TiAlN etc,all trivalent chemical coatings. Aluminum is a trivalent metal and consequently aluminum shows an affinity with trivalent coatings.
Iron based metals are quad-valent and have little affinity with trivalent coatings and therefore coatings offer lubricity to steel but not aluminum. Most aluminum tools are therefore
left uncoated. One exception is Di-boride coatings which are as 'greasy as a butchers prick' in aluminum. If you have trouble, particularly with some 'sticky' aluminum grades,
like some of the 5000 series and most of the 1000 and 3000 series then Di-boride may just save your bacon.
Craig
Aluminum doesn't bond to ZRN coated carbide and the extra speed they allow makes a huge difference to cutting performance - especially on high speed constant torque spindles that hit peak power at 18,000-24,000rpm+.
The extra heat from cutting aluminum at 20,000rpm+ is easily managed with the coolant. That is, as long as I feed it fast and deep enough to avoid the tool rubbing.
If I was buy my spindle again, I'd probably go for one with more speed and less power. It would be more useful to me as most of what I do requires small tools.
Large tools never seem to fit in all the crevices on the molds I make. According to GWizard I'm only ever using a tiny fraction of my spindle's available power and torque. I could do the same with less wasted power and noise.