[sabastion]

oops...read above post

[sabastion]

I think you're kinda picking the fly poop out of the pepper here.... What is or is not a pleasant noise is a matter of personal opinion. I have a stepper machine (X2), and a servo machine (knee mill), and I like the sound of both - neither is preferable, they're just different. In any case, when cutting the sound of the tool will completely swamp the sound of the drive motors. And one most small benchtop machines, especially the X2, the spindle motor is absolutely deafening

Regards,
Ray L.

Hmmmm...then something is wrong with his CNC mill or something is going on because I defiantly hear a very annoying noise that sounds like (I described it wrong in earlier post) some sort of weird computer language. Like a bunch of beeps, blurps, whurs and what not and I can deffinately hear it over the machining and the X2 motor. Listening back on some of the other videos that sound isn't there.

Take a listen http://www.youtube.com/user/hossmach...42/jE4RHd3o_ZMand see if you can tell me what this noise is. It starts at time stamp 0.50...

If its not the machine or parts of the machine....Ill stop being concerned right now...thanks
Richard

[hoss2006]

That's the sound it makes using the MPG, you won't hear that under normal jogging or feeding.
Hoss

[sabastion]

That's the sound it makes using the MPG, you won't hear that under normal jogging or feeding.
Hoss

Oh, ok...cool! no more worries.

My uber newbness is really shining Lol
Richard

[yantra3d]

"Even without a fault, you'll be operating over only a small portion of the motors usable RPM range - kinda like buying a 500HP V12 Ferrari, and never driving it over 25MPH."

Because this is an x3 that we are talking about I would argue that the torque you are implying via a belt reduction system would be WAY more than you will EVER need for a mill this size - if you have some real servo motors. When I was using the keling servos they were way underpowered even with the 3:1 planetary gearheads! So perhaps the quality of the servo makes the difference here. In my case the the direct drive aerotech's have way more power than the keling's using the 3:1 reduction. If using real servos (as I mentioned in my last response) belt reduction then would truly be overkill for a mill this size and so, as I said, it's just not required.

"I have a stepper machine (X2), and a servo machine (knee mill), and I like the sound of both - neither is preferable, they're just different."

Hmmm, what kind of servos are you using on your mill? Mine are almost completely silent! They have nowhere near the noise that my lathe steppers have so I'm not so sure about that frankly.

"In any case, when cutting the sound of the tool will completely swamp the sound of the drive motors."

When I was using the stock X3 spindle motor setup I couldn't even hear the tool cutting the material! I have never had steppers on the mill so I can't say that they would actually drown out the cutting sound but, I do know that with the servos I hear nothing but the cutting sound from the tool which is why I said that it was a nice bonus.

"2. I have seen in some pictures that it looks like servos require the use of brushes (more noise and wear)...is this true? I haven't noticed this with stepper motors"

The brushes do not create any extra noise to be concerned about.

"Steppers have no brushes and are extremely durable when crashed. No damage will happen to the stepper itself."

No damage would ever be sustained by the brushes in the event of a crash.

Like Ray said, brushes are not an issue worth considering. If/when they do wear out you can replace them in a minute or so with new ones for next-to-nothing.

[SCzEngrgGroup]

"Even without a fault, you'll be operating over only a small portion of the motors usable RPM range - kinda like buying a 500HP V12 Ferrari, and never driving it over 25MPH."

Because this is an x3 that we are talking about I would argue that the torque you are implying via a belt reduction system would be WAY more than you will EVER need for a mill this size - if you have some real servo motors. When I was using the keling servos they were way underpowered even with the 3:1 planetary gearheads! So perhaps the quality of the servo makes the difference here. In my case the the direct drive aerotech's have way more power than the keling's using the 3:1 reduction. If using real servos (as I mentioned in my last response) belt reduction then would truly be overkill for a mill this size and so, as I said, it's just not required.

What that says is the your current servos are significantly over-sized for the machine, while your previous ones were significantly under-sized for the machine. That's fine if you're able to come across the servos at a bargain price, as you apparently did. But, if designing on a level playing field cost-wise, your solution would yield a more expensive system than right-sized servos with belt reducers that would give you exactly the same performance.

"I have a stepper machine (X2), and a servo machine (knee mill), and I like the sound of both - neither is preferable, they're just different."

Hmmm, what kind of servos are you using on your mill? Mine are almost completely silent! They have nowhere near the noise that my lathe steppers have so I'm not so sure about that frankly.

850 oz-in NEMA34 DC servos, exactly like the ones Keling sells. Mine are also almost completely silent. There is a slight whine at speed (you're probably not ever getting yours going fast enough to hear that). There is also a periodic (about once/second or two) quiet "chirp" from the servos dithering when stopped. If yours are tuned to be truly silent when stopped, you likely have not tuned them for best performance.

"In any case, when cutting the sound of the tool will completely swamp the sound of the drive motors."

When I was using the stock X3 spindle motor setup I couldn't even hear the tool cutting the material! I have never had steppers on the mill so I can't say that they would actually drown out the cutting sound but, I do know that with the servos I hear nothing but the cutting sound from the tool which is why I said that it was a nice bonus.

Same with the X2, as I indicated - The spindle motor is so bloody loud, I had to wear ear protection whenever it was running, even with a belt drive. That's one of the great things about the knee mill - it's relatively quiet, even when removing 8 cu. in./minute. The universal motors on the low-end mills are just painful.
"2. I have seen in some pictures that it looks like servos require the use of brushes (more noise and wear)...is this true? I haven't noticed this with stepper motors"

The brushes do not create any extra noise to be concerned about.

"Steppers have no brushes and are extremely durable when crashed. No damage will happen to the stepper itself."

No damage would ever be sustained by the brushes in the event of a crash.

Like Ray said, brushes are not an issue worth considering. If/when they do wear out you can replace them in a minute or so with new ones for next-to-nothing.

Regards,
Ray L.

[yantra3d]

What that says is the your current servos are significantly over-sized for the machine, while your previous ones were significantly under-sized for the machine.

Theoretically, I agree. However, in practice it works. And, it works quite well in fact.

But, if designing on a level playing field cost-wise, your solution would yield a more expensive system than right-sized servos with belt reducers that would give you exactly the same performance.

I think that this would be a fair assessment only if you were to factor in the cost of the additional parts involved for a belt reduction system (i.e., timing belts and pulleys, mounting hardware, plus the time involved, etc...). All things considered it may not be that much more (if any) to bypass the belt drive altogether.

Anyway, I just wanted to mention that it can be done and based on my personal experience it works well. When someone (not to mean you) says that you HAVE to have a belt reduction to drive an x3 with servos I feel inclined to add my own experience on the matter. My opinion is that it is NOT necessary given a powerful enough motor. That is of course only my own personal experience in regards to servos on an x3.

Also, I am not implying that servos are better or even recommending them over steppers in anyway. I just happened to go that route on my mill and so I am offering up my experience for potential retro-fitters. Based on my own experience - all things considered - I don't regret it at all. At the same time, I also don't regret having steppers on my lathe.

[sabastion]

Thanks for the help and info guys...

I have decided on stepper motors

[sabastion]

now to decide on a stepper motor...I will be using Digital Stepper Motor Driver digital stepper driver

Gecodrive only has 2 (one or the other)

Keling has a large number of stepper motors with varying 0z/in sizes, shaft dia. sizes, single/dual shaft configurations, 4-6-8 wires

Decision is keling...though I'm concerned about not being able to call and talk with them personally. Not having to wait for reply for support or sales is a major plus. Seems you can only communicate with them by E-mail. I don't like to do business this way so it might sway me to go with a different manufacturer. Which would cause me to choose a different stepper driver also...that sucks.
EDITED keling just sent me an e-mail with their ph number. wow...i just sent them an email request for their ph number 30 minutes ago and I already got a response AND ON A SUNDAY OMG!!! SO I will be using keling after all...woot

All I've seen in these conversions are geco and keling...are there any other reputable manufacturers or suppliers for stepper motors that will communicate with you by phone?
Thanks
Richard

[rpovey]

I have 3 of those drivers sitting waiting to be wired, but I still think the G540 is hard to beat for any mill of that size.
The only reason I'm not using one for my G0704 conversion is it can't provide the current for the larger steppers.

I've had good experiences with Keling, he's a reseller not a manufacturer.
There are a number of vendors who'll sell you steppers, and drivers, I've used Keling, CNC4PC and a couple of EBay vendors over the years.

On the first page Hoss recommended a G540 with Kelings 381 in-oz steppers, I'd be inclined to follow that advice since he's actually converted an X2.

[sabastion]

I have 3 of those drivers sitting waiting to be wired, but I still think the G540 is hard to beat for any mill of that size.
The only reason I'm not using one for my G0704 conversion is it can't provide the current for the larger steppers.

I've had good experiences with Keling, he's a reseller not a manufacturer.
There are a number of vendors who'll sell you steppers, and drivers, I've used Keling, CNC4PC and a couple of EBay vendors over the years.

On the first page Hoss recommended a G540 with Kelings 381 in-oz steppers, I'd be inclined to follow that advice since he's actually converted an X2.

what current does your steppers require...the digital stepper drivers from keling are adjustable from 0.5 - 5.6 amp

[rpovey]

I'm using 570in-oz steppers that require 5A, the G0704 is a lot larger than the X2.

The G540 will only put out 3.5A, I have one on my Sherline mill paired with 270oz-in steppers.

[sabastion]

the KL-8056D and the KL-5056D are both adjustable from 0.5 to 5.6 amperes. Too big for my purposes (from a power supply stand point?) but probably suitable to yours...
Richard

Wish I could see a buying a G0704 for my first mill...oh well

[rpovey]

Yes as I stated I have 3 5056's sitting in a box waiting for me to find some time and wire up

[sabastion]

WOW...you did. How the heck did I miss that??? Sorry Lol

[yantra3d]

"On the first page Hoss recommended a G540 with Kelings 381 in-oz steppers, I'd be inclined to follow that advice since he's actually converted an X2."

I'd 2nd that... 3.5A should be a perfect size for a stepper motor. Anything larger would be overkill IMO.

[sabastion]

"On the first page Hoss recommended a G540 with Kelings 381 in-oz steppers, I'd be inclined to follow that advice since he's actually converted an X2."

I'd 2nd that... 3.5A should be a perfect size for a stepper motor. Anything larger would be overkill IMO.

Definitely taking his advice on stepper motors but I wont be going the g540 route (or any multi axis single driver) because if one axis fails you have to replace the whole unit...I learned that lesson years ago with proprietary All in one or integrated hardware computer parts in things like compaq, dell, gateway, HP and so on.

I will be going with the digital drivers...I just have to wait til tomorrow to find out if their compatible with the 381 oz/in motors. It should be since it falls within the 0.5 - 5.6 adjustable amperes range. The supply voltage is what confuses me...1 of them is [COLOR="Red"]Supply voltage up to +45 VDC[/COLOR and the other is Supply voltage up to +70 VDC so I might have to make an adjustment on stepper motor choice from 381 oz/in

[sabastion]

Servo is better as it is more accurate and reliable, besides, the prices different is small.

small? huh? I looked at a 230 oz/in dc servo 149.00 for one. a nema 23 381 stepper is 69.00 and a 350 oz/in servo is 79.95. I dont see how thats small, thats almost twice as much as a 381 stepper. That was just a quick look see.
Richard

[rpovey]

Definitely taking his advice on stepper motors but I wont be going the g540 route (or any multi axis single driver) because if one axis fails you have to replace the whole unit...I learned that lesson years ago with proprietary All in one or integrated hardware computer parts in things like compaq, dell, gateway, HP and so on.

A G540 is actually a breakout board with 4 independent G250's as drivers, you can replace them independently.
The 381 oz-in steppers are 2.8mH the optimum voltage is marginally over 50V.
The G540 is an excellent driver for those steppers, but use what you want.

[sabastion]

A G540 is actually a breakout board with 4 independent G250's as drivers, you can replace them independently.
The 381 oz-in steppers are 2.8mH the optimum voltage is marginally over 50V.
The G540 is an excellent driver for those steppers, but use what you want.

ok...I didnt see that in data for g540. I'm definitely glad I joined this forum, you guys are very knowledgeable and helpful...TY
Richard