Messages

1

General Mach Discussion / Re: PMDX and extra parallel port?

« on: May 14, 2011, 05:04:23 PM »

I just bought a 126 as well and was told that it can multiplex I/O on the pins not used by the drives, but that my plan was kind of pushing the limits.  Therefore I bought the 108 daughter card for 8 expanded inputs on the second PP, thus allowing me enough inputs for my pendant. 

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General Mach Discussion / Re: Mini-ITX D525 Atom and Slim XP

« on: May 11, 2011, 02:52:50 PM »

Thanks Greg for the reply.

I do plan to run a 4th axis once in a while.  There used to be some great Core-i3 deals but they seems to be gone now that the new chipset is out and they are having issues with the SATA controller.  Maybe see if I can find an Atom/ION combo with PP.

3

General Mach Discussion / Mini-ITX D525 Atom and Slim XP

« on: May 10, 2011, 10:30:29 PM »

Due to the fact all my computers and laptops are running Win7 x64 I was a bit hood-winked into buying a SmoothStepper, and am now just finding out it doesn;t necessarily do all the things Mach is capable of through the PP.  Not that it isn't a great option, its just that I have plenty of misc older hardware and Windows licenses to build a dedicated x86 system for the same or less money.  That and I would like to be able to test and compare the old PP to the SS option.

I was wondering if anybody is running a Mini-ITX Intel D525 Atom (Dual core 1.8GHz) integrated motherboard??  If so which brand are you running, how much RAM, and of course any quirks or issues using the integrated PP?   I am looking at the Gigabyte board as I have used them almost exclusively in workstation and HTPC builds and never had one fail yet, that or the Foxconn which is a bit cheaper but also uses DDR2 ram which I have a few sticks lying around.  Lastly, is the thing bearishly slow, I know I setup a netbook once and it was painfully slow and it was the latest dual-core offering from Dell.  However that was running more intense media applications, how does Mach perform on an Atom, any issues with display refresh using the DRO's etc. in Mach considering the IGP on the Atoms?  I am planning on running a touchscreen display off what ever I purchase, though I have to confirm the monitor will be compatible with VGA.

Regarding OS, I have a bunch of XP Pro licenses along with one or 2 remaining 7 licenses.  Is there any loss/benefit going one way or the other.  Regarding XP has anyone built a stripped down Slim XP install for dedicated use with Mach?

Thanks.

4

General Mach Discussion / Accuracy of Homing Devices? Pro's and Con's of Different Sensors

« on: April 30, 2011, 08:27:22 PM »

After a lot of searching, and much reading, I have found many different opinions and suggestions on the types of sensors/methods used for homing.  I need to outfit a mill and lathe and am looking for the best accuracy and repeatability while maintaining robustness.  Figuring that there will be metal swarf, coolant and oil potentially reaching these sensors.  From what I've read electrical/magnetic switches such as inductive proximity, and hall effect sensors, can shift register due to temperature and electrical interference in the region of a few .001's over the course of a few hours.  On the plus side there are no mechanical part to wear out and it easy to get IP65/67 version's.  On the other hand you have a micro-switch which does not suffer from the previously mentioned climate shifts and electrical interference dilemma, but have mechanical mechanisms that can wear out and fail, that and it's hard to come by waterproof versions cheaply.  

So if you guy's wouldn't mind listing what systems you are using, and/or have tried and scrapped for something better, and what level of accuracy/repeatability you experience.  Is the position shift from some types of sensors only critical if you have to perform manual tool changes over the course of a long cycle, or are using setup plates for repeat parts w/o re-zeroing on the workpiece?  Also, in regards to proximity switches if you use them can you list the model# and the sensing distance.

Which is most accurate and repeatable, and has the least worry of false triggers of the following types of systems:

1) Proximity (inductive)
2) Micro Switch
3) Laser
4) Hall Effect
5) Other...

Thanks.

5

General Mach Discussion / Re: Converting a Clausing Mill and Lathe, have a couple Q's

« on: April 29, 2011, 11:39:37 PM »

Thanks again TotallyRC for the answers.  I have been doing scripted searches of both CNCZ and here for answers to questions, but come up short often.  There are so many BOB's and secondary peripherals that no 2 systems are alike.  

Basically I decided to just buy a bunch of stuff and figure it out, anything I don't use on the mill I plan to re-purpose for the lathe.   So I bought a Smooth Stepper, the PMDX 126 w/ input board, a 5v psu, prox sensors, CUI encoders, cables, a Gecko 203v to power a bigger stepper for the knee, a Mitsu servo with 21:1 planetary for possible rotary axis or lathe tool changer, terminal blocks, and other bits.  

I checked out the Wildhorse sensor and it looks pretty neat, do you know the average positioning accuracy of it?  Other than that I am trying to determine the best sensors/switched for homing/limits and figuring the pulleys and screws for the drivetrain.

Any other help or suggestion is appreciated, Thanks!

6

General Mach Discussion / Re: Converting a Clausing Mill and Lathe, have a couple Q's

« on: April 28, 2011, 02:31:27 PM »

Mike,

Thank you for taking the time to answer my question point for point.  A few follow-up questions for you or anybody else that wants to answer or give suggestions:

1) Does the SmoothStepper have a encoder feedback plugin (for quasi closed loop) like the Sound Logic board?

2) Which BOB would you recommend?  The PMDX 126 looks really nice, but by time I purchase a SS and the BOB/PoKeys I am well into PLC price territory.  However pre-programmed plugins seem like a nice option vs. programming ladder and modbus.

3) One plus side I see is the SS can potentially run off a mITX PC since it is USB potentially saving money.  Is there a known unit that many people are using w/o issue?

4) If I drop the encoders for table positioning, can you suggest some robust switches and proximity sensors, and how many are needed each for table limits, homing, and tool-setting.

5) Regarding the AMT encoders, the only difference between the 102 and the 103 is just the angle of the socket pins?  Anybody sell a specific cable that fits the pin-outs?

6) Any special components I need for probing so I can get them ordered as well?

Thanks again.

7

General Mach Discussion / Converting a Clausing Mill and Lathe, have a couple Q's

« on: April 27, 2011, 11:22:30 PM »

Hi there new to the board.  

I am planning to CNC a Clausing 8520 mini-mill along with a Clausing 11" lathe (Harrison M250) and have a couple questions.  

For the mill I have decided to use a Gecko G540 since they are just up the road form me and figured it would get me started and easily acquainted, well that and I'm feeling a bit lazy and don't want to have to do any extra wiring.  I am not looking for any fast rapids etc. so the plan is to run Nema 23 steppers geared down.  From what I have read the Gecko will handle my 4-axis as well as my spindle VFD, but lacks any decent amount of I/O's.  

I want to add at least 1 MPG along with the accompanying axis and multiplier selectors, and then of course there are the cycle stop, e-stop, run, hold, etc. switches.  I plan to maintain manual ability on the mill for sure, and use encoder feedback for DRO.  Therefore I obviously need an additional BOB, the ones I have been looking at are the SmoothStepper and the Sound Logic (roger machine) encoder boards.  So my questions are the following.

1) What are the strong points, weakness's of either of these, and can they both equally accomplish the necessary I/O's?  

2) Is it possible with either of these to fully control either Gecko or DMM servo drivers (if I choose in the future) and/or send pulse-train to other AC servo drivers?  

3) Can either of these boards do tool offset positioning and/or edge limit/homing using the encoder with a proper plugin in Mach??  

4) My mill has the original screws and they have ~.006" of lash, do either of these handle backlash compensation, or does Mach do this? Or should I replace the screws?

5) If neither of these can perform all my requests, is there another board that can?

6) Which are the best affordable through-shaft encoders that will interface well with either board for position feedback?

I have ordered the G540, steppers, and purchased a Mach license, now I just need to figure the BOB and encoder situation plus any other bits that I need to make a complete and proper system.  If neither of these bob's with encoders can perform limiting, which are the best switches to use, proximity, or mechanical?  

Other than that I am open to suggestion, any advice regarding things I should avoid, or try to implement, or if anybody has CNC'd one of these machines already and want to share their thoughts it would be greatly appreciated.  Lastly, is it at all possible to save to 2 instances of Mach one for mill and one for lathe, which would allow the use of a single computer, HMI interface, and bob to control 2 machines (each having their own drives and encoders) by swapping the DB25 input from one set to the other.  These are just home shop machines right next to each other, so I was thinking I could make one really nice setup (touchscreen, MPG's, AB switches and buttons) that could control both machines?? 

Thank you for any and all help.