Water cooled chinese spindle collets, Advice from owners please

[Ali Kat]

I assume that the spindles are made on CNC equipment and it's probably not going to be straight forward to redesign the rotor with a larger nose to accept the larger diameter ER collets and nut that would be required to go from ER 16 to ER 20 for instance.

As I said previously, the manufacturer may be prepared to make a "one off" but I would think that the cost would quite high.

Is it not a case of just ordering the CNC3040 with a larger spindle to cover a larger range of sizes? The 2.2 kw spindle can handle up to 1/2" and is man enough for most jobs including steel milling. I would have thought that this would be cheaper than getting a lower powered spindle but with a bespoke larger collet size.

Ali Kat

[Jonathan]

Yep but better than sat on a shelf or in the scrap bin.!!

True, but even better would be to just couple it to a brushless RC motor and keep it as a high speed spindle. With the right motor it could be better than new...something like this:


http://www.hobbyking.com/hobbyking/s...dProduct=11187

Plus it's no big deal or expense to change the bearings know is it.!

Assuming you can find tapered roller bearings the same size, but that's rather unlikely as I think those spindles use a pair of 70xx series bearings?

Is it not a case of just ordering the CNC3040 with a larger spindle to cover a larger range of sizes? The 2.2 kw spindle can handle up to 1/2" and is man enough for most jobs including steel milling.

Ordering the CNC3040 without a spindle and getting the 2.2kW spindle separately might be easier? Either way it's worth asking.
I've found it's not really man enough for steel milling. I've made a couple of bits from mild steel with my cnc router and that spindle, but the problem is the torque at low rpm for that type of spindle is so low that you're limited to only very small cutters and running them a bit fast. A VFD with vector current control would help matters, but it's still going to have limited torque and rigidity.
If you actually want to cut steel regularly you need a lower rpm spindle and a much stronger machine than a CNC3040!

[JAZZCNC]

True, but even better would be to just couple it to a brushless RC motor and keep it as a high speed spindle. With the right motor it could be better than new...something like this:

Yep thats an option but not one I'll be taking and for what I need it will be fine just the how it is.

Assuming you can find tapered roller bearings the same size, but that's rather unlikely as I think those spindles use a pair of 70xx series bearings?

But I have lathe and know how to use it so again no great deal, but again won't happen has it won't be needed for my needs.

Is it not a case of just ordering the CNC3040 with a larger spindle to cover a larger range of sizes?

Ah ah best laugh I've had all morning.! . . . My experience with these small crap machines is they struggle to even lift the Z axis with 2.2KW weight never mind be usable.!!

I've found it's not really man enough for steel milling. I've made a couple of bits from mild steel with my cnc router and that spindle, but the problem is the torque at low rpm for that type of spindle is so low that you're limited to only very small cutters and running them a bit fast. A VFD with vector current control would help matters, but it's still going to have limited torque and rigidity.

Not strictly correct.!
Yes using standard milling cutters and techniques then yes they are way too fast but with correct high speed tooling designed to run dry and high speed milling techniques then they work fine in steel. The down side being the cutters are expensive and it can take longer because you can't hog big lumps out but it still does a good job without stressing the machine or spindle.