Hello Guest it is June 19, 2019, 03:50:56 AM

Show Posts

This section allows you to view all posts made by this member. Note that you can only see posts made in areas you currently have access to.


Messages - motorhead101

Pages: 1 2 »
1
General Mach Discussion / Re: Accurate homing
« on: August 23, 2007, 07:00:00 AM »
I don't know what made me think of it, but is the NISAT 6 axis controller still available?  If you want  a high end system for free, try that one, if it's even still around.  I remember running accoss it years ago, atleast 5 years, only catch is it runs under Linux, and I highly doubt it has a support forum such as Mach, but what other company does?  It was supposed to set the standard for PC controllers, issued by the NISAT, and was free to download, fully functional.  Does anyone remember this or even know what I'm talking about?
Michael

2
General Mach Discussion / Re: Step losses in specific displacement
« on: August 22, 2007, 02:37:24 PM »
I used the Logitrol "Low Cost CNC" system.  And I don't reccomend them to anyone.  Basically, it's a 50V DC power supply, Gecko 320 drivers, US Digital encoders, and Pacific Scientific motors, supposed to be 1800oz/in.

  When I recieved the system, the Pacific Scientific motors had encoders pre-installed that were drawing too much current, 150 mA, which is 3 times what the Gecko driver reccomends since the encoder get's it's power right from a onboard regulator in the G320's.  I blew 2 of the Gecko drivers immediatly.

   I emailed back and forth with Steven Kennef from Logitrol to try to get the system working.  He claimed that the Gecko drivers were under warranty and that it must be a problem with the G320's as they were having some issues with "mosfet suppliers", or some other bogus crap like that.  So I took the system apart and sent the drivers back to Gecko for evaluation.

   After recieving and evaluating the Gecko 320's, I talked to thier engineer on the phone to discuss the problem.  He asked a lot of questions and informed me that the encoders that were installed at the time, "remco's", were drawing too much current causing the servo drivers to fail.  He also told me that if the drives were repairable, they would repair them for free of charge, even with Gecko paying return shipping!  But all 3 drivers were beyond repair......  Gecko did replace 1 servo drive for free under thier "one time stuff happens policy", which they didn't have to do and I was very greatfull for!  The other 2 I had to pay for, as well as 3 new encoders that the Gecko engineer reccomended from US Digital Encoder.

   Steven Kennef refuses to admit fault to this day.  He did send a $140 refund towards my costs of repairing the system that was supposed to be plug and play that his company built.  He claims that he can't afford to refund me at this time because his wife is sick in the hospital and he's having financial issues.  I apologize, I hope the best for everyone is health and happyness, but not being able to seperate business from personal issues and affairs is poor business.  I'm not even going to discuss that further, we'll just say my life isn't perfect at the moment but I don't use that as an excuse, and definatly no to customers.


   Sorry for the long story, just pissy about the Logitrol deal and I want to warn others of my dealings with them.  Basically, it's a 50V power supply, Gecko 320 drivers, an isolated break out board, sevo's and encoders that are wired up in neat looking boxes.  My personal opinion is if your at all capable or atleast willing to learn, just do it yourself....  I will if I do it again.  Plus the knowlege gained will be worth 10 fold of what you save as far as money when you can diagnose and repair your own system.  Logitrol didn't design or wire anything special and all of the components are available from diffrent suppliers and I'm sure that there's people here in the Mach forum that would be more then happy to help you locate and source.  Plus you can probably save a lot of money, I paid Logitrol $2600, plus $600 for replacing damaged drivers and new encoders, and a $400 phone bill for calling Steven in Australia....  Lesson learned.

   And I highly reccomend Gecko drivers.  Thier customer service is amazing!  And this is also why I love the Mach controller!  This is an amazing support group and I'm very impressed with the knowlege and helpfulness of some of the members!

Michael 

3
General Mach Discussion / Re: Accurate homing
« on: August 21, 2007, 05:05:36 AM »
I don't think that any of his problems are with the mach program or using Mach 3 as a controller.  I think he just needs to accept the fact that the E-stop is going to dead stop the motors, they will lose position, and his limit swith's are junk which have nothing at all to do with Mach 3.
Michael

4
General Mach Discussion / Re: Accurate homing
« on: August 21, 2007, 01:26:58 AM »
I have 2 retrofitted bridgeports.  One runs the Mach controller and one runs AHHA! 

The Mach controller dead stops the servo's when you hit the e-stop.  If the servo's are in motion, more than not, they will fault because they cannot de-accelerate fast enough, it's a saftey thing.

The AHHA! contoller is actually running a stepper system, and the way the contoller is set-up right now, it de-accelerates the steppers when the e-stop is pushed, no loss of position.  The controller can be made to dead stop the system when the e-stop is activated, it's in the parameters somewhere, but as you know AHHA! is not interactive as Mach 3 is, I'd have to get the book out. 

I'm also guilt of using the e-stop to stop the machine.  On the AHHA! system, I use the e-stop if I want to clean the chips off a drill.  Can't do that with Mach.  I have a Logitol series 3 pendant and use the "pause" button to stop the mach 3 controller, works great.

As for the homeing, you get out what you put in.  Garbage mechanical switch's are good for limits, not homeing.  They don't work for crap on either of my machines.  They get you to within .005 in most cases.  If I have to e-stop the Mach controller, I re-home the machine, then re-indicate or edgefind and reset my work coordinates.  Pain in the ass, yes.......  And when I shut down the Mach controlled machine and power back up, I always reset zero.  The servo's tend to jump a bit when they are powered up which sometimes throws the position a couple of thousands.  The AHHA! stepper machine keeps it's position for as long as you don't stall the steppers, even after power down and restart.  But the AHHA! contoller is no comparison to Mach 3.

I don't think it's going to matter what contoller you use if your limit switch's aren't accurate.  Try inductive switch's or using the reference from the encoders.

Michael 

5
General Mach Discussion / Re: Step losses in specific displacement
« on: August 21, 2007, 12:51:36 AM »
You said your having problems when the machine changes directions, right?  Check the backlash settings, disable them if they are turned on.  I had a problem when I started my machine up.  I'm running servo's, so they won't stall, if they go out of position by 128 encoder counts, they go into fault, or shut down.  Initially, my backlash settings were set to 20% of set speed.  This gave me problems in the same place every time in the same programs.  At certain points, not many, but the same place every time, the servo's would fault where they were supposed to make a direction change.  I now have the backlash speed set to 1% of set speed and have no problems, and I don't notice any problems as far as machining quality either, my initial worry is that the endmill would dwell.  BTW, I rapid at 96ipm and cut with a ballmill at 90ipm using constant velocity, no problems since.

Michael

6
General Mach Discussion / Re: limit switches and cable sheilding
« on: August 11, 2007, 01:22:03 AM »
I had this same exact problem when my limit swithes were wired in series normally closed.  No matter what I tried, the MACH program would say that a limit switch tripped for absolutly no reason.  I tried everything to isolate the wires, ect.

I ended up wiring my limit switches in parallel normally open, not one problem since, and it doesn't make a diffrence if the limit switch cable is wrapped around the servo power cables...

Should fix your problem, exactly what's causing the problem I'm not sure, but that will fix your problem.

Michael

7
I used the Omron limit switch's.  They are great if your using them for a limit switch, but not repeatable for using them as a home switch.  I can get a variance of 0.010" depending on how tempermental the limit switch decides to be when I home out the axis.  It's clearly just an inexpensive switch, they only cost $15 each, roller plunger style and the plunger has quite a bit of slop.  Problem is now I'm looking for decent home swith's with the same mounting bolt dimesions.  I highly recomend paying for decent home switch's, or home/limit switch's.  The cheap ones will work good for the other end of the axis.

Michael

8
General Mach Discussion / Re: How fast is your G00 Rapids?
« on: July 17, 2007, 07:35:27 PM »
motorhead101

 you might want to consider powering the knee too,just don't wast the money making it fast.i fixed mine as a slow
 knee and a fast z.the knee has 16 inches of travel and the z has 6.works pretty good ,i just call on it in the code
 as a c axis.

 bill
Excellent idea, thanks!

9
General Mach Discussion / Re: How fast is your G00 Rapids?
« on: July 17, 2007, 03:30:56 PM »
Quote
I hve run mine on 67000 mm/m a little over 2600ipm, but wont force it at this speed, I think I´ll settle with 45000 mm/min


Best reg
Cory

2600ipm?  With ball screws?  I didn't know a ball screw was capable of handling a feedrate or rapid that high.  What kind of machine?  AC servo's?  What servo drive are you using?

10
General Mach Discussion / Re: How fast is your G00 Rapids?
« on: July 17, 2007, 03:26:07 PM »
I used the Elrod Machine Quill retrofit for the Z.  The Elrod quill is very nice, and expensive too!  But you only get 4" of travel because of how the ballnut release works.  I think the next machine I do I'll try to power the quill from the arbor that you mount the quill feed handle to.  I didn't want to try to power the knee because it is so heavy and I for-see problems.  I ended up putting the Mach controller back to 35KHZ and I get 96ipm rapids.  I use ball mills for contouring aluminum at 90ipm and run carbide inserted facemills at 60ipm and chips fly!  I used to run high end mold machines at 200-300ipm using 6mm ball mills making inserts for molds.  Using the slower feeds on aluminum, I can just cut a little deeper, leaving a scallop, but they are easily polished out.

Pages: 1 2 »