Spindles - Lingering Questions

I didn’t either, so I purchased a 2.2kw. Having a spindle rather than a router is excellent. More control, much less noise (even with air-cooled).

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No ER20 on the 1.5. The ER16 is the one I got. It handles up to 3/8" shanks. Ordered Monday. Delivered yesterday (Thursday.) You can get a better price on the VFD elsewhere, but I liked the idea of having a single vendor with everything stocked in US, US based support, and a one year warranty with claims handled in the US. Here’s the link for the spindle: High-Torque Stepper Motor, Stepper Motor, Driver, Stepper Motor kit, DC Servo Motor, DC Servo Motor kit, Stepper Motor Power Supply, CNC Router, Spindle, and other Components.

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Thanks for the excellent input.

I haven’t ruled out the router yet. My first thought was to keep things simple, and I thought I might even start with a DeWalt 660 heavy duty cut out tool (collets for 1/8" & 1/4") which I bought some time ago and never used. I don’t see any good way to mount it to the X-35, though.

I also looked for actual routers with 1/2" collet capability, and found several, but none seem compatible with the standard 1F mount or the 80mm option, either. Maybe there are some options I didn’t find, though?

The ER20 collet appeals to me for flexibility. I already have assorted cutters that I’ve used with my other machine tools and not all are 1/8 or 1/4 or 1/2 sizes. At least some would be suitable for moderately high RPM depending. So there would be some benefit in being able to use what’s available.

From what I’ve seen so far, getting ER20 collet capability means going with a 2.2kW spindle, and most of these seem to be water cooled.

The lower speed spindle idea really appeals to me, since I anticipate that most of my work will be at lower speeds. I don’t know if I need full torque for my work, and I also don’t know what the typical 2.2kW spindles can do. Possibly this is a “try it and see” situation.

But I haven’t bought anything yet. I’ll do some more searching and probably mull things over for at least a few days yet.

Thanks again.

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Thanks for the great input and helpful information. It clarified my thinking about this.

Funny that I was only thinking about this as a 110 V machine. As you mentioned, the 2200W VFD takes a 20A input at 110V, so then I would need another 110V feed for the 1F machine and other stuff.

That’s workable, but I do have 1-ph 220V in my shop for other machine tools. So going to 220V for the spindle makes good sense.

I’ll admit that the 2200W spindle idea still scares me a little, since my other metal working tools have nothing bigger than 2HP motors. They are geared way down, of course, with plenty of cutting torque, so I can’t help think that a 3HP spindle could do a lot of damage at high feed rates–I’m reassured that a lot of folks seem to have made that choice and are making it work.

I’m wondering what you and others are doing for cooling: do the water pumps that come with the spindle kits work well or what other approaches have been adopted?

Thank you.

I know next to nothing about VFDs, I can spell VFD and after that it’s all questionable. :slight_smile:

I know some have used a 2.2KW VFD with a 1.5KW spindle so I am assuming they have set some limits on the power out to the spindle.

Is it also possible to limit the power to a 2.2KW spindle so it operates like a 1.5 ? That way you get the ER20 collet flexibility but the reduced power of a 1.5 KW spindle and also a lower total amp draw on the circuit for the VFD.

Then if you ever wanted to in the future add a dedicated 20A circuit for the VFD you could reprogram it to run the spindle at full power. And you wouldn’t have to buy a new, larger spindle which would leave you with a 1.5KW spindle to sell or put on the shelf as a spare.

Hey Bob,

As you can see in the typical Motor Characteristic Diagram on the bottom of the datasheets, e.g. this air-cooled or this water-cooled 2.2 kW 80 mm ER20 24,000 RPM spindles have a power that is proportional to the speed. If you run them at 100 Hz they spin at 6,000 RPM and they take in 0.6 kW, at 200 Hz they spin at 12,000 RPM and take up 1.2 kW, and if you run them at 400 Hz they spin at 24,000 RPM and they consume 2.2 kW of power. Note that the torque stays constant over this range at about 0.95 Nm (Unfortunately I haven’t found such nice datasheets for the cheaper spindles Huanyang sells).

In my opinion it would make no sense to want a ER20 collet with not enough power. A ER20 collet is able to take tool shafts with a diameter of up to 13 mm(!). The reason why spindles with ER20 collet with less than 2.2 kW don’t exist is that it is assumed that you do not want your tool to get stuck in the workpiece or to be slowed down when choosing serious feedrates.

I think if you don’t want to consume electricity, CNC is not the right thing for you. Add another half to once as much power for the dust extraction to this (when milling wood).

I think you should imagine the power of the spindle as the ability to achieve a feedrate without being slowed down.

A CNC machine is not you on a hand-fed milling machine. It is a robot that does the work for you.

Yep. Just my comment. It’s different than what I’m used to and I’ll clearly need to adapt my thinking for CNC. But I’m here to learn.

All tools require a decent level of respect to be used properly and safely, especially the powered ones.

Hey Dave,

Well spoken. My candidate for the Tip of the day.

As far as woodworking goes 2hp really isn’t a very large motor. I wouldn’t be concerned one bit about a 3hp spindle. If something was to happen I don’t think the difference between 1.5kw and 2.2kw is going to make a bit of difference.

Where it will make a difference is when you get a spoilboard surfacing bit. Most people with the Makita go with a 1" diameter bit. I’m using a CMT bit with replaceable carbine inserts that’s almost 2 1/2" in diameter spinning at around 8,000 rpm. It has a 12mm shank so you need a ER20 collet minimum. The extra width makes surfacing a board a much faster job.

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That is not my concern at all.

You can use a 1.5kW VFD to power a 2.2kW spindle. You just aren’t going to get the full power out of the spindle. A VFD will just shut down if the current exceeds it’s limit to avoid damaging itself. The spindle will still reach maximum speed. If you are limited on the power you have where you are going to put the 1F then this could be an option.

Yes, that’s my concern for the present location where I will setup. Somewhat limited on available power since no 240 volt power available and no space in the breaker panel to add another circuit.

To be sure I understand if I use a 120 volt, 1.5KW VFD with a spindle rated at 2.2KW it will still reach full RPM of 24k but be limited by the max output of the VFD.

End result will be a 80mm spindle with an ER20 collet that can run up to 24k RPM but will only have the power of a 1.5KW spindle. At a later date I could get a 240volt, 2.2KW VFD and run the same spindle at full power.

Hey Bob,

inside the VFD, you set the Rated Voltage (from Motor Nameplate), the Rated Current (from Motor Nameplate), and the Motor Number of Poles (from Motor Nameplate) of your spindle.

With the current limitation, the VFD is able to protect the spindle from overcurrent. A VFD with rated 2.2 kW 220 Volts Output has a Rated Current Output Default Setting of 10 or 11 A. If you have a 1.5 kW 220 Volts Spindle you may change this setting to approx. 7 A in order to prevent overloading your spindle. You may also do this with a 2.2 kW spindle if you think it makes sense.

However, the output voltage range of a VFD depends on its input voltage. As far as I know VFDs, those for 200-240 Volts input provide an output voltage (motor voltage) of 200-240 Volts, the models for 380-480 Volt input an output voltage (motor voltage) of 380-480 Volts, and, as far as a manufacturer offers them, the 100-120 Volt models usually provide an output voltage (motor voltage) of 100-120 Volts.

That would mean that if you buy a 110-Volt spindle now and operate it on a 110-Volt VFD, you cannot easily operate it later on a 240-Volt VFD.

But there is the option of buying a 220-Volt spindle and a special step-up, Voltage Doubler VFD that works with 100-120 volts input voltage, but outputs the three-phase current for the spindle at 220 volts, e.g. the Huanyang “B-T” Models or the Invertek Optidrive ODE-3-210058-104#.

But it seems that such Voltage Doublers are much more expensive than a normal VFD.

I think if you have to set up your CNC on a location without 240 Volts you’d be better off with buying everything in 110 Volts and reselling both later.

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So for my situation it seems my best bet is a 120V 1.5KW VFD and Spindle, then upgrade everything to 2.2KW when I have a place with a 240V circuit I can dedicate to the CNC.

Why do I want the larger spindle and not the 65mm diameter/800W? My thought is a larger spindle will have a larger diameter shaft and bearings so able to handle higher loads. So even though I may never use anything larger than a 1/4" bit the spindle with more torque than the trim router or the smaller spindle should be up to the task. I wanted the ER20 collet to be able to use 1/2" bits because my experience with 1/4 and 1/2 inch bits in routers has shown me that the larger shank bits perform better in most situations.

So looking at this VFD and spindle from www.automationtechnologiesinc.com
image

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Hey Bob, hey Dave @circuitbug,

yes, and longer life. With 80 mm you can’t do much wrong. There is room for the good ingredients.

But the decision whether ER16 or ER20 collet must be found based on your needs and requirements. It’s hard to decide if you don’t have the experience. One can not generally say this is better.

If you want to ask others specifically for the ER16 and ER20 decision, a more general CNC forum would be better than this one specifically for Onefinity CNC, which has only few members. Most CNC fora I know are in german, but there is https://www.cnczone.com/forums/ in english.

As for my decision to the ER16/ER20 choice, I I described it here. Why 65 mm spindle has disadvantages here and here.

If you buy the same things as Jim @Webb, you may have a look at if he’s going to get it to work!

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Deescalating from DEFCON 5. It works. No thanks to the instructions or the manual. Sorry, I’m not usually grumpy, but this has been an unexpected challenge. Not sure I’d have made it without your help.

Jim

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@Aiph5u” alter ego is "Captain VFD.":grin:

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Yes, I saw that thread and I’m following along.

I’m leaning toward a 1.5KW 80mm spindle, but air or water cooled, which to choose.

Air would be simpler to implement/setup, but I am concerned about how much debris will
be drawn into the spindle by the fan. Will I be tearing it apart every n hours to clean it?
Is keeping it clean as simple as blowing some air through it periodically? I doubt that.

Or should I get away from the dust issue and go with a water-cooled version and deal with
the extra hoses and pump and coolant reservoir.

Bob, with the dust collector running I get very little in the way of dust. The spindle is tall, so the fan is quite a ways away from the work surface. Also, I’m breaking in the ER16 spindle right now and it is quite quiet. It does get a bit loud at 18000 and above. It is, however, like night and day compared to the router.

Jim

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