[cadfish]

Hi everyone,

A little about my idea :idea::
I work for a company who does design work for Reuland Electric. My company also designs our own high speed, high HP motors. The previous one we designed is supposed to be 30,000 RPM and 200HP :rainfro:. It will be used to test jet engines. :rainfro: :rainfro: :rainfro:

About me:
I have always wanted to design a hobby sized, but industrial quality, CNC milling machine or a lathe. From the reading I have done, the spindle is the first thing that I would need to design.

My idea is (if there is any interest):
I could have 10 to 20 of these spindles made which would reduce the manufacturing cost. Currently the CAD model I have is about 7.5" OD, and 24" long (dimensions are subject to change as needed). I am doing all the design work at home and on my own time, so there will be limited to no additional engineering costs.

Would anybody be interested in purchasing a USA made spindle at the speed and HP in the title? Or am I dreaming?

Any Comments or Questions?

[osphoto]

I'd be interested in purchasing a spindle made in the USA. Not sure I need 10HP.

My Hitatchi router does well. I cut hardened tool steal the other day with a 1/4 bit @ 8000 RPM and shallow cuts. Yea, I was very surprised that it did so well.

What kind of torque we talking?

Could we use 1/8 bit up to 1/2?

110 or 220 single phase?

Just my thoughts

[cadfish]

osphoto,
I am currently only in the mechanical design stage. I am using the longest stack I can get for the diameter that I am using. For those who don't know the what a stack is, it the part of the motor that has all the copper wires wrapped around it.It is currently 10.75" long.

I could probably offer different sizes in HP (1HP, 1.5HP, 2HP, 3HP, 5HP, 6HP, 10HP). I would just have to change the frame length. The RPM could raise up to 40K RPM at 1HP.

I did some math and was pretty impressed with my findings. Not that I ever would, but I could take a .250 endmill through hardened tool steel at 140 IPM at .125 inches deep, and using a dull tool and only use 10.01 HP.

I am thinking I would like to use an ER32 in my machine, so it could go up to 3/4".

As for the electrical I think I would have to ask the people what the want, 110, 220, 1phase, 3 phase, 60 hz, 50 hz etc.

[cheetahcnc]

Sounds interesting.

[carlcnc]

cadfish
I've always wondered why an American company doesn't do spindles,
granted it's hard to compete with Chinese, but price isn;t everything

that said I think 3 and or 5hp 3phase 220v would be most common,
[although I own a few 7.5 and 10hp Italian ones]

at least ER25 if not Er32 for collets.

air cooled or water cooled??

Carl

[asuratman]

cadfish,
It is brushed or brushless, ac or dc. Do you plan to make bldc or blac for smaller dimension? What price? Thanks.

[cadfish]

carlcnc,
yeah, it is hard to compete with the Chinese, but looking at the 10K spindle motor sold by Keling CNC, and the very terrible reviews that I have heard makes me want to stay away from them. I also hear it takes a long time for them to get up to 10K.

About 5 weeks ago the company I work for did some testing of a few of our motors. 0 RPM to 10K and back down to 0 in 3.2 seconds! We put these motors through their paces for 80 strait hours. The "specialty motors" made by a different company for our customer lasted only 10 hours. We did better, and lets just say the customer was very happy.

The bearings will be from Timken or SKF. They are NOT going to be "Made in China."

I am designing the motor to be water cooled with grease packed bearings. There will also an option to have oil cooled and oiled bearings; which is the way I will be going.

asuratman:
The motors will be brushless, AC, there may be smaller motors in the future. If they are bldc or blac I could not tell you now. As for the price, that I can not say yet. Once I complete my designing I will see about price.

Don't know, but if my company is involved in any of the designing of the motor for what ever reason and there are confidential internals. To keep the internals confidential I doubt any of these motors will leave the US or Canada.

[osphoto]

I'm in the market to purchase a spindle. I need to beef up my spindle holder and figured, I'd rather build for a better spindle then build for my current router.

I'm looking at the spindles found on ebay, the 2.2KW to the 4Kw. I need very little run out for my 1/64 bits and want the higher RPM's.

Figured, I'd get the spindle then purchase the VFD from here in the US.

To bad you don't have a spindle sooner then later.

Keep up the work!

[cadfish]

Osphoto,

As for the spindle holder, I am trying to design it with mounting features attached to the motors. Sorry I can't attach a picture, I tried twice.

As for the runout we try to keep it under .002 and that is on the big motors.

I could offer a 5HP (4Kw) in a smaller frame size.

[RICHARD ZASTROW]

cadfish, .002" or .002mm? Machine tool spindle runout of .002" is a NO-NO. I realize you are referring to your big motors, what would you be expecting on your proposed spindle motor?

Dick Z

add: BTW, SKF manufactures spindles here in the USA at Grafton, WI.

[asuratman]

Hi cadfish,
Do you plan to post how to design this motor spindle here. It will be very good to know. Thanks.

[cadfish]

Dick:
our large motors have runout of .002 inches. I would personally like to guarantee a runout of .0001 or less. But of course the majority of the runout will come from the bearings. I hear many of our bearings are .0002 each.

I like that Timken has the radial high marks displayed on their bearings OD's and ID's, I plan to have the spindle shaft inspected and the low marks 1/bearing indicated. the same scenario will be preformed on the bearing housings. It is all in the tiny details, which I haven't got to yet.

asuratman:
I do not plan on posting may pictures of the motor internals. I am only in the rough design stage. I would suggest finding out how big of a motor you would want and then go from there. Find an electric motor manufacture close to you, and see if they sell any partial motors, and if possible see if they have a catalog that has dimensions of their stators and rotors.

then you need to work on the housing. Do you want the motor to be air cooled? Liquid cooled? Then you would need to integrate the stator and the fins/cooling channels in to the housing.

Next the shaft needs to be designed. How are you going to balance the shaft? Drill holes, add balancing rings? If you use balancing rings, at what speed do they separate from the shaft due to centrifugal force? What kind of bearings are you planning on using? Conrad style? Angular contact? At certain speeds the rolling elements will separate from the shaft/inner race of the bearing. At what speed will the shaft start rotating around its own center of gravity (called Critical Speed)?

What are you using for bearing lubricant? Oil? Grease? How are you going to seal the motor so the lubricant doesn't drip out onto your machine table?

These are only a few of the details I am paying attention to. Once I my spindle designed, I need to start making fabrication prints, inspect all mating parts for clearances/interferences.

The details are endless If you decide to design your own spindle. I hope you are good at math, trust me, there is a lot of it.

[Monkey King]

Catfish,
How much wil it cost?
How heavy is it?
Can you provide any size dimension?

[cadfish]

Monkey King

Cost: At this time I am not sure. I am still in the "rough design" stage.
Weight: at this time the 10HP is going to be over 30 lbs.
Size: in the rough design stage I can not guarantee any sizes.

Cadfish

[RICHARD ZASTROW]

Cadfish, Radial run-out of an ABEC 7 angular contact bearing between 18 and 130mm i.d. is less than .0001" (2.5 micron). I believe most precision bearing manufacturers do or will mark the high spots.

The specially selected and matched bearings, like ABEC 9, are even more accurate but also more $$$$$$$$$$$!!!!!!!

Dick Z

[cadfish]

It looks like I will be using 307 15 degree ABEC 7 angular contact, on the cutter end. ABEC 9's will be available upon special request.

I will likely be using smaller on the encoder end. Yes I said encoder, I want to have rigid tapping. Does anybody have an opinion on if they want to get their own encoder vs having one supplied, pre-installed on their spindle?

[asuratman]

cadfish,
Having our own encoder I mean the one is easy to find in the market is OK or you install one that easy to find would be fine. This because in case encoder damage, we can get one easy.

[diyengineer]

It looks like I will be using 307 15 degree ABEC 7 angular contact, on the cutter end. ABEC 9's will be available upon special request.

I will likely be using smaller on the encoder end. Yes I said encoder, I want to have rigid tapping. Does anybody have an opinion on if they want to get their own encoder vs having one supplied, pre-installed on their spindle?

If you could make it compatible with U.S. digital encoders that would be nice, and an easy add on.

Also, for the majority of people in this forum who are limited to single phase power (240V), you have to keep in mind power requirements and how much $ we have to spend on a VFD to actually use the spindle.

Also i don't believe you have mentioned a auto tool changing option?

I think you could have a lot of success in the 1-3HP range. Most hobbyist users on here all buy the 1.5kw or 2.2kw spindle.

[BobWarfield]

A of that power and rpm range ought to be set up for tool changes and a standard taper rather than a permanent collet chuck. A 30 taper ought to be about right. I wouldn't go R8, not clear that's a happy taper at 20K rpm!



2 cents,

BW

[RICHARD ZASTROW]

cadfish, you may want to consider lubed-for-life sealed angular contact precision spindle bearings. They're a little harder to find but are available, especially 30mm bore and larger.

We just bought a few from GMN. I know others have them as well. I have a 2003 SKF sealed high precision catalog with both steel and ceramic balls.

Dick Z