[MikeSibley]

I'm planning to build a cnc kit at home for my woodworking. I hope to do things in my retirement for fun and maybe make a few bucks so I don't want a pure hobbyist machine, but let's call it an intermediate machine. I'm thinking about a 4x8 or a 4x4.

I've studied sizes, brands, China vs US retailer, software both CAD/CAM and operation, etc.

Looking for a little hlp and advice.

I've decided on a 2.2 KW and VFD spindle when I get my machine. Beyond the air-cooled or water-cooled option, I've noticed a lot of discrepancy in spindles and their uses. If you simply do a Goober search, of course Amazon comes up with about the first 50 items. On their pages, all seem to be Chinese (wording is not normal US English usage is in the description) and some say that they will not run less than some particular speed, others say good for engraving, not milling. I believe that buying on Amazon just might be a crap shoot even they all say 220 Volt, 2.2 KW. Some say 400 hz when I know that US line current is 60 HZ. Maybe that is something on the secondary of the VFD?

But, when you look at the US machine suppliers' pages versus Amazon, the cost of a spindle is 5-10 times the cost of those on Amazon. How does one decide which Chinese import at either site is worthy?

I noticed that some use air cooled, Others have liquid cooled. From what I have read, people say that air cooled spindles have fans and blow more dust around the shop. Also, some say liquid cooled are quieter, but I can certainly see if something went wrong with a liquid cooled machine, wow, what a mess especially if using antifreeze. Also liquid cooled machines might have more things that can break. And with any machine, if you use it, it will break. Would I need a radiator since I live in the Southern US where it is really hot?

Everybody has a budget so before diving off head first into mine, I want to make the best decisions that I can with the advice of you good folks who have already been there and done that.

I get verbose sometimes, but I'm at a break from my work and thought I would reach out.

Thank you!

Mike

[Al_The_Man]

You require a VFD to run these spindles up to their max. of 24000rpm, the VFD has to be programmed for a lower limit range of 6krpm, otherwise you burn out the motor.
You get what you pay for, the Chinese products are lower quality, hence the price.
Al.

[ger21]

But, when you look at the US machine suppliers' pages versus Amazon, the cost of a spindle is 5-10 times the cost of those on Amazon. How does one decide which Chinese import at either site is worthy?

Can you post some links and ask specific questions? Without knowing which spindles you are referring to, it's hard to answer this question.

You'll find that most spindles are either 300Hz or 400Hz, with 300Hz being 18,000 rpm spindles, and 400Hz being 24,000 rpm spindles. These spindles are 3 phase motors, with the 3 phase voltage at high frequencies generated by the VFD.

Sticking with 2.2Kw chinese spindles, you can break them down into round, or square bodied.

Starting with the round bodied, there are two varieties, water cooled or air cooled. Both are about $200 for the spindle only.

All of these cheap spindles have limited power at lower rpm. So most should not be run below 6000-8000 rpm. The air cooled spindles have small, ineffiecient fans, so they can get hotter at low speeds than water cooled, and can not be run at low speeds as long as a water cooled. But it depends on the loads it's seeing.

My preference is the air cooled, which eliminates the hassles of water cooling.

At $200 (or less), these should be considered disposable. They won't last forever, but many people get 5 or more years out of them. And while most claim to have a 1 year warranty, don't count on it.
Because these are so cheap, quality control can be all over the map.

While I've never seen one in person, the square Chinese spindles are basically round spindles in a square extrusion. These are all air cooled, and have a larger fan than the round air cooled spindles. The larger fan makes them louder, but they'll also run cooler. These tend to cost a bit more, usually in the $300-$400 range.

The only "expensive" Chinese spindles I'm aware of are from UGRA CNC.
These spindles have much better quality control, are individually tested, and have a warranty and support you can count on. For some, that's worth the additional cost. For others, it's not.
I believe the spindle that AVID CNC sells is the same as the spindles from UGRA CNC.

[NIC 77]

This gentleman likes his spindle and says it has low runout. I'd be tempted to buy the same one he did.

https://www.youtube.com/watch?v=pKPKe19Dh9s

[philba]

This gentleman likes his spindle and says it has low runout. I'd be tempted to buy the same one he did.

skip to 6:40 for the spindle part.

[MikeSibley]

Thanks guys!

[mactec54]

Thanks guys!

Just so you are not confused with your power supply frequency of 60Hz this has nothing to do with what you program into the VFD Drive this is just the supply power spec's, your 24,000 RPM 400Hz spindle spec's is Programed into the VFD Drive, the VFD Drive has to be rated for 400Hz or what ever your spindle motor spec's are