Messages

131

General Mach Discussion / Re: Servo Drive Review. First 4 drives Gecko, Viper, Rutex, Leadshine

« on: September 04, 2009, 11:14:42 AM »

The drives have been given a good work out for a week now, they maintain accuracy and run very cool, and have not needed to be reset.

The drives should not need to be reset unless something goes wrong. And sooner or later, something goes wrong. What is important is that the drives are able to initiate an e-stop in Mach. I strongly suggest you set up and test that function before you have need for it.

According to the manual, the Viper200 should be able to be reset by cycling the control power without killing the HV, so that part shouldn't be an issue.

Hi Simp'36,

Yup, nice job on the repair, hope those tiny wenie little critters with 471 marking don't need changing, just look at the size of them compared to the 8 pin DIL package... we'll need a soldering iron the size of a pin !

I have done some SMT work myself and hand soldering that stuff is almost as hard as the strain on your eyes.

Re: the Viper 200s, my estop circuit is hard wired (mushroom head crash stops and "very"end of limit travel switches) at the moment, nocks out the spindle VFD as well.
Next step is to wire in the 1st satage travel limits and the Viper fault signal to the BOB Estop I/P . This will disable the step / direction OPs to prevent any further movement.
The "very" end limit will kill everything in the case that a drive has run away.

that is the philosophy anyway :-)

Those Dugongs do look good though ;-)

ATB
Derek

132

General Mach Discussion / Re: Best way to convert step and direction to +/-10V

« on: September 03, 2009, 05:01:27 PM »

Hi Steve,

I haven't used these but might do the job for you.

http://max-mod-shop.com/index.php?option=com_content&view=article&id=47:yapsc10v&catid=17:-yapsc&Itemid=4

CNC zone thread..  http://www.cnczone.com/forums/showthread.php?t=74532&page=3

ATB
Derek

133

General Mach Discussion / Re: Servo Drive Review. First 4 drives Gecko, Viper, Rutex, Leadshine

« on: September 03, 2009, 04:51:51 PM »

Here is a quick review of the Viper 200.

My Colchester / Ailam Crusader control went U/S so required a rapid conversion to Mach + new drive system.

I contacted Larken and explained I needed the drives quickly. I ordered 3 - 2 for the machine + 1 spare.
These were despatched swiftly with all connectors / jumpers and a programming lead included.

The PC boards apear to be wlll constructed and finished, I could not see any mounting or soldering defects. Nice...
It took a few weeks to design and build the new control system, Viper manual is up to date, (manual should recomended / detail using fans / additional heat sinks if end mounting).

The drives were commissioned as per the manual, powering up the logic side and checking coms - no problem there.
Check of the PSU - OK 130VDC
Power onto the drives, YES, we have movement.
Tuning is easy, if not a bit of a guestimation exercise - the manual does give some help but its a bit thin (fortunatley my business partner has designed small digital servo drives so understood the PID settings and generally how to tune by feel.)
The tuning process took about 1 hr per axis, checking the stiffness of the drive and ensuring stability. All done manually, i.e twist the pulley by hand and check the movement of the axis on a dti.
Overshoot is the most difficult thing to detect and tune out.

The drives have been given a good work out for a week now, they maintain accuracy and run very cool, and have not needed to be reset.
Well pleased.
The Anilam control had max rapids of 4m/min...quick test with the Vipers we had this up to 6m/min (and could have got more) but having just got the lathe working again and not wishing to break it, we set the max rapids at 4m/min

The only thing I would like to see is mounting recomendations in the manual and a graphical means for seeing the motor position vs demand signal to aid tuning.

The CNC Drives Dugong looks interesting - might try these to replace my stepper driven Bridgeport drives...mmmm.. decisions decisions.

Either way, the Vipers do a good job. ***Recommended***

ATB
Derek

134

General Mach Discussion / Re: Do i need a bigger pc for mach..

« on: September 02, 2009, 12:40:59 PM »

Hi Chris,

Have you gone through all the optimisation steps?

http://www.machsupport.com/downloads.php 2nd up from the bottom

I had a cranky PC running a Lathe - crashes / blue screens / etc.
All went smoothly after the optimisation steps.

ATB
Derek

135

General Mach Discussion / Re: USING DIFFERENT STEPS PER UNIT

« on: August 31, 2009, 09:02:59 AM »

Hi Rich,

I have a metrix X and an imperial Y ball screw  AND the standard ACME on the Z set up on my BP - it's been working fine for over 18months now ;-)

ATB
Derek

136

General Mach Discussion / Re: Lathe spindle brake

« on: August 29, 2009, 12:47:27 PM »

Looks good.
Does that tool post index or is it just a standard dickson?
Is the lathe based on a Student? Looks a bit smaller than a Triumph.
Hood

Hi Hood,

The Lathe is a Master 600 (ex college with very low milage)
the tool post is a standard Dickon (manual change jobbie)
I have an indexer from an automated assembley machine that I might have a go at fitting as a tool turret now it's been upgraded to mach. The indexer is solid and very accurate.
It has 6 positions, so I can fit 6 turning tools + 6 boring / drills + possible to fit gang toling in some positions.... (thinks crawl first before running ;-) )

ATB
Derek

137

General Mach Discussion / Re: Lathe spindle brake

« on: August 29, 2009, 08:52:14 AM »

Bit more to do, mainly to the homing limits.
I might try to use the Z channel from the encoder in "series" with the slide switch to provide an accurate home / reference position.

Here is a quick photo.
http://img42.imageshack.us/img42/9465/img6551.jpg
ATB
Derek

138

General Mach Discussion / Re: Lathe spindle brake

« on: August 23, 2009, 12:59:30 PM »

Easy to fix by opening the screenset in screen4 and double clicking on the button and changing it to a VB button. 
After that then go into Mach and View menu then load screens and choose your renamed screen.
Next Operator menu then Edit Button Scripts, that button should be flashing, click on it and then enter the VB you want into the button and close and it should now work as planned
Hood

Hi hood,

I'll have a go at that once I have worked out what I am going to have a go at!

ATB
Derek

139

General Mach Discussion / Re: Lathe spindle brake

« on: August 23, 2009, 10:33:14 AM »

You tried the optomisation steps detailed on the downloads page?
Hood

Hi Hood,

Went throught the optimisation steps again (properly this time!) and set the PC option to Standard PC in device manager.....ta darrrr !
Now works fine.
The M3 M5 macro to control the brake was stil not working so I reloaded mach and this is now functioning perfectly. (must have scrambled something when I had a few crashed running the driver test.

Entering M3 or M5 in the MDI line works fine too.

The only thing I have noticed is that the brake is not released if I start the spindle using the icon (in manual or auto screen) and ignores the delay I have programmed in the M3 macro. However the stop spindle icon does control the brake as required.
Does the icon run a different macro from that used by M3?

We have run a quick test to cut some "real metal" 
Don't you just love it when a plan comes together :-)
Thanks for your help, we're chuffed to bits!

ATB
Derek

140

General Mach Discussion / Re: Lathe spindle brake

« on: August 22, 2009, 03:32:07 AM »

You tried the optomisation steps detailed on the downloads page?
Hood

Hi Hood,

I went through the optimisations steps - I'll run thro again in case I missed anything.

A more positive note - using another PC, the Viper 200s are working well. I have done as much tuning of the PID as I can just cutting air.
Generaly, it is looking very good, just need to sorth the "blasted" PC :-)


ATB
Derek