Messages

51

General Mach Discussion / If using Mach and a Smooth Stepper, did you reduce your max servo speed?

« on: February 20, 2009, 04:38:15 PM »

Not really sure how to ask this but if you are using Mach and a smooth stepper, are you running your machine at the maximum speed it is capable of or did you manually limit the speed since the smooth stepper allowed it to travel too fast to feel safe?

Here's the reason I ask the question:

I'm getting ready to bring an old CNC veritcal milling machine up to current technology and have a question about servo drives. The Supermax YCM-40 currently has servo drives model SEM 30M4-59, 2400 rpm, 142 volts, 30 pulse amps. I've read on a forum that these use around 10A continuous.

In my research I've found that some Viper 200 servo drives would work with this setup (rated at 170V, 20A) however carry a heavy price tag of $240 each.

Gecko 320's are rated at 80V, 20A and are only $119 each. I think I understand that the Gecko's would work however my max speed would be reduced. Is this the only downside?

I've noticed in a lot of posts that when people switch to a smooth stepper board they could get very quick rapid speeds however backed them down for safety concerns. So it seems that quite a few people don't use their max speed anyway?

I'm just curious how slow the machine would be setup like this or if it would only be noticed in a production environment where every second counts?

Thanks for any feedback...

52

General Mach Discussion / Re: Need advice on which breakout board is needed?

« on: February 19, 2009, 03:28:58 PM »

Just got my paypal money request from Greg for the smooth stepper board.  He must be close to shipping them out like you said.

Can't wait 

53

General Mach Discussion / Re: Need advice on which breakout board is needed?

« on: February 18, 2009, 06:22:16 PM »

Excellent news, I hope to get alot done in the next few weeks...

54

General Mach Discussion / Re: Need advice on which breakout board is needed?

« on: February 18, 2009, 03:48:22 PM »

http://www.warp9td.com/index.php?option=com_fireboard&Itemid=33&func=view&id=930&catid=7

Hood

Very nice... thanks

55

General Mach Discussion / Re: Need advice on which breakout board is needed?

« on: February 18, 2009, 03:16:59 PM »

You mean to attach it directly to the pins on SS board with the appropriate connector?  I just read thru the SS manual again, here's some specs:

6 axes of coordinated movement plus a spindle.
Spindle control may be Step & Direction, PWM, or discrete on/off.
Maximum Step Frequency is 4 MHz
I/O: Port 1: 12 Outputs and 5 Inputs
Port 2: 12 Outputs and 5 Inputs -or- 4 Outputs and 13 Inputs
Port 3: 6 Inputs (3 differential and 3 single-ended)
Grand Total: 24 Outputs and 16 inputs, or 16 outputs and 24 inputs, depending upon
configuration.
All outputs are 5V CMOS logic.
Port 2 pins 2-9 have CMOS thresholds (input and output).
All other inputs are TTL, except for 3 of them that are differential and are intended to be used with an
encoder. Except for Port 2 pins 2-9 and the differential inputs, all other inputs are Schmitt Triggers.
All outputs capable of sinking or sourcing 32 mA.

32mA isn't a whole lot for controlling some relays, so I may have to do something there.  Easy enough though.

Thanks for the help, makes alot more sense now...

I sent an email to www.warp9td.com asking about availability (I got on the waiting list a week or two ago just incase).  If they are still 4 weeks out, do you know if they have any dealers that sell their products for them that may have some in stock?

56

General Mach Discussion / Re: Need advice on which breakout board is needed?

« on: February 18, 2009, 03:00:07 PM »

Now that you mention that, the previous owner did say when in low or high range on the spindle it does run it in reverse.  I had forgoten about it until now.  I don't plan on doing any tapping with the mill until I've got some more experience under my belt.

Since it seems that smooth stepper would potentially make it a smoother running system and does allow for a wider range of encoders to be used, it may be the way to go...  Then I would only need to add a breakout board for additional inputs/outputs to the SS board.

57

General Mach Discussion / Re: Need advice on which breakout board is needed?

« on: February 18, 2009, 02:26:08 PM »

I do not know what rapid speeds this machine is capable of?  How do I determine the step rates of my servos?  They are SEM servos model 30M4-59, 2400 rpm, 142 volts, 30 pulse amps?  Or is this strictly a function of the encoder I mount on it?

I do not need spindle speed control to start with, however my VFD can accept 0-10V to control the speed if needed.  I figured at some point I might as well get it to work.  The mill has a vari-speed pulley setup on it now.  I can always worry about this piece later and just select the speed manually for now...

The viper manual shows the step/dir inputs as opto-isolated.

I like the K.I.S.S. principle so keeping everything on their own boards sounds better to me, I just need to figure out what I need.

Hood, the electronic gearing you mentioned, is that related to the "Step Multiplier Select" available on the vipers?  It offers 4X multiplier, 6X, and 10X.  I assume this is to electronically gear down the servo, meaning on the 10X setting, it takes 10 times as many steps to move it 1" as it did on the 1X setting?

Probably a stupid question (but reveals my knowledge of milling machines).  Why the need to reverse the direction of the spindle?  Aren't must cutters made to spin the same direction while cutting?  What am I missing here?

The servo's have tachometers on them now so I will have to purchase encoders. 

Thanks for all the replies!

58

General Mach Discussion / Need advice on which breakout board is needed?

« on: February 18, 2009, 11:48:44 AM »

I've done enough reading to go cross-eyed...  Lots of great info though.  Getting ready to start my conversion on my mill.  Here's the build thread I just started:

http://www.cnczone.com/forums/showthread.php?t=73820

I'm thinking I will need to use the Viper 200 drives for my servo's.  What all is necessary up stream of the servo drives?

I thought since my new PC doesn't have a parallel port on the back I would use a smooth stepper board but I just read that it doesn't replace a breakout board and a breakout board is still needed?  If so, I do have a parallel port connection on the motherboard I can connect to.  It's a new PC dedicated to running the mill so would there be any downside to this?  (not using a smooth stepper).

Breakout Boards

So some breakout board choices I've come to by searching are the PMDX-122 shown here: www.pmdx.com/PMDX-122/ for $81.

the C11T shown here http://www.cnc4pc.com/Store/osc/product_info.php?cPath=33&products_id=181 for $124.

The Bob Campbell breakout board shown here http://campbelldesigns.net/breakout-board2.php for $130.

or the Bob Campbell combo board shown here http://campbelldesigns.net/Combo-board.php for $245.

I get alittle lost looking at breakout boards as each manufacturer has about 3 models with little differences...

I plan to run it as a 3 axis machine and add a 4th axis later down the road. 

Would like to have a charge pump monitor, E-stop button, PWM signal to VFD, inputs for home switches, end of limit switches, etc.  Also like to build a pendant with controls on it as well, but I assume this will require additional inputs (possibly another breakout board for input into the PC)?

Also need to find some encoders for the servos (US Digital?)

59

General Mach Discussion / Re: Rutex and Mach3 problem

« on: February 04, 2009, 04:35:11 PM »

Did you ever get the problem resolved?  I'm thinking of going with Rutex for my retrofit and would like to know if you gave up on them or found the issue.  Thanks...

60

General Mach Discussion / Re: Vertical mill Mach 3 retrofit using existing steppers/drivers, advice?

« on: January 27, 2009, 11:43:16 AM »

So if they are in fact DC servos, how does this change my plan?  I need an additional StepDir to analogue converter?

Based on my reading on this site, it appears servos accept different types of inputs based upon make and model.  Is this typically a analog voltage level with polarity changes for direction changes?

Attached are two of the wiring drawings.