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Gerald_D
Registered
Username: Gerald_d
Post Number: 568
Registered: 11-2005
| | Posted on Friday, December 01, 2006 - 01:30 pm: | 
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Art Fenerty "asked" this morning:
Hi Guys:
Im doing a quick survey. How much interest is there is the next board Ill be
releasing to Mach3's interface,
the ncPod is just about ready and is pretty much complete and operational. , its
specs follow..
Approx size: 7.5 x 7.5cm's.
75000 Pulses per second,
USB connection
6 axis.
6 home inputs. Board handles homing sequence.
6 general inputs.
5 general purpose outputs.
1 Spindle output. PWM 75Khz base frequency of PWM.
Retail Cost: ~$125.00 each.
The Price is an approximation, but is expected to be about there..pretty
exceptional when one considers the costs of normal components in a cnc
system..There will be OEM pricing for systems makers.
The ncPod is running well in testing, we have probably 2-3 weeks of testing
left to do, so Im thinking release around Christmas or shortly after. This is a
completed module, and will be released as such, not as R&D, but as a completed
device, ready to run in USB from laptops or whatever, on much slower computers
(I suspect) than a normal Mach3 printer port driven system. (though that remains
to be tested. )
Its showing great robustness, accuracy, and speed. It is not readily
noticable that you arent running a printer port, other than it is smoother and
faster than a Printer port. I consider its level to be inbetween a G100 and a
printer port. I will at time of release be making a web page showing the various
modules that can be run by Mach3, and a list of capabilities and restrictions
each device may have. Ive found not every device will give the same
capabilities, (nor would one expect them to). So for Mach3, in 2007, a list of
devices will appear, and users will pick from the basic, (printer port) to the
Pod, the G100, the Galil, and at the top, I expect, the Delta-Tau.
So what Im wondering, is how many of you would be interested in an ncPod,
being that it would replace your printer port, and allow you to run from Laptops
and such.. Of course if one is running well on Printer port, your fine to stay
with it, but my opinion on Vista, is that printer port drivers will not be
written, it doesnt make much sense to as most Vista computers will not have a
printer port. This device will be the Vista solution for Mach3,
for general purpose , where the G100, Galil and Depta Tau's are a higher
capability unit more geared to the higher end. Im pretty impressed with the Pod
thus far, and Im curious as to possible responce. We may as well thrash it out
now, before release, in terms of any questions.  , so if yout think youd
switch to or use such a device, let me know..Im just trying to get an idea of
the number of people I could expect to jump into a Pod...
(Just stirring the waters abit.. )
On a lighter note, as of next version, to set up inputs in a printer port
system, , the system will simply ask you to press the switch or activate the
input, it will then automatically set the port #, the pin # and the "Low active"
to appropriate levels for you. (IT will even enable the signal.. ), so
setting up Mach3 is starting to get easier. (I setup all my inputs on a test
machine in less than a minute.. (Course I can do that anyway on a good day. )
Anyway, those are a couple of the things about to come your way, many things
are now starting to come together all at once, it will be an exciting time for
the first few months of next year as you get more toys and capabilities to use
and play with.. (And if I ever attempt to take on this many projects at once
again, someone, please, anyone...just shoot me.. its only mercifull.. :-)
Thanks, ( finally seeing some lights way up ahead...)
Art
www.artofcnc.ca
http://ncpod.oemtech.com/
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fabrica
Registered
Username: Daya
Post Number: 100
Registered: 10-2006
| | Posted on Sunday, December 03, 2006 - 04:31 pm: |
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Gerald, What is this. Can you please explain the role it plays on a CNC router. |
Gerald_D
Registered
Username: Gerald_d
Post Number: 572
Registered: 11-2005
| | Posted on Sunday, December 03, 2006 - 04:52 pm: |
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If it proves reliable in a few months time, and the price is still right, it will probably replace the PMDX-122 that I use for the MechMate now. It will not make your machine run any better, smoother, quieter, faster unless you are going to use slow PC for Mach3. The ncPod will do some of the work (it has its own brain) that your PC will have to do for PMDX-122 now. But, with a good PC and the PMDX-122, you are okay.
I have a feeling that the traditional "parallel port breakout cards" like the PMDX-122 will be considerered "obsolete" in a year's time IF the USB connection proves to be reliable, and IF the price can be near $120. But, it is not going to give an obvious performance benefit |
Greg Holt
Registered
Username: Greolt
Post Number: 7
Registered: 08-2006
| | Posted on Monday, December 04, 2006 - 12:09 am: |
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You might be surprised Gerald. I think the ncPod will give a smoother pulse stream.
Whether you will be able to tell the difference on the shop floor is another matter.
And yes there is the fact that it has to live up to expectation and prove its self. |
Mike Richards
Registered
Username: Richards
Post Number: 29
Registered: 05-2006
| | Posted on Monday, December 04, 2006 - 05:52 pm: |
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What interests me the most about the ncPod is the 75,000 pulse per second rating. Mach3, on my PC, can generate 45,000 pps; however, if you look at the pulses with an oscilloscope, the pulse train is 'ragged'. In comparison, the pulse train from the G101/G102 that I have is almost perfect, with the capability of pulsing much faster.
If the ncPod can pulse at nearly 2X the speed of the PC and if it can produce a smooth pulse stream like the G10x, it would be a great improvement over the parallel port. |
Greg Holt
Registered
Username: Greolt
Post Number: 9
Registered: 08-2006
| | Posted on Wednesday, December 06, 2006 - 08:40 am: |
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Posted this pic elsewhre and thought some here may be curious as to what it looks like.
Now if I can just get this pic to work
 |
Gerald_D
Registered
Username: Gerald_d
Post Number: 596
Registered: 11-2005
| | Posted on Wednesday, December 06, 2006 - 05:02 pm: |
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Amazingly few components! That heatsink looks a little power hungry though? But then, that heatsink is only as big as my thumbnail!
Would the developers of these things please stop making them smaller - us oldies cannot see them anymore. My soldering iron's tip will span about 4 points at a time! |
Greg Holt
Registered
Username: Greolt
Post Number: 10
Registered: 08-2006
| | Posted on Thursday, December 07, 2006 - 11:57 am: |
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According to Carl who makes and I presume designed this "It requires 5 vdc regulated at about 250 ma". |
Gerald_D
Registered
Username: Gerald_d
Post Number: 833
Registered: 11-2005
| | Posted on Thursday, February 08, 2007 - 08:04 pm: |
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http://ncpod.oemtech.com/ |
James Webster
Registered
Username: Wti
Post Number: 11
Registered: 02-2007
| | Posted on Tuesday, February 20, 2007 - 11:36 pm: |
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We ordered one of these to try out.
They are introductory priced at $105 USD with shipping included ($110 USD international). You can paypal them at: support@oemtech.com
Not only do notebooks no longer have parallel ports, but both of our new desktops are lacking them too. Looks like the printer port has gone the way of the dinosaurs. |
Gerald_D
Registered
Username: Gerald_d
Post Number: 963
Registered: 11-2005
| | Posted on Wednesday, February 21, 2007 - 06:52 am: |
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Parallel "printer port" extension cards for desktops will probably be available for a long time still.
I would still advise someone today to build a MechMate with a parallel breakout card because the support is solid. Converting from a parallel breakout to a ncPod should be very simple and economical. |
James Webster
Registered
Username: Wti
Post Number: 19
Registered: 02-2007
| | Posted on Saturday, March 03, 2007 - 04:35 am: |
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Here is the wiring diagram for the ncPOD:
http://www.cncteknix.com/ncpod/ncpod_diagram.pdf
It specs that it needs 5v regulated at .5 amps. I wonder if the 5v rail off of the computer could deliver the current. Anyone know how much a hardrive draws? |
Gerald_D
Registered
Username: Gerald_d
Post Number: 1084
Registered: 11-2005
| | Posted on Saturday, March 03, 2007 - 07:30 am: |
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I don't particularly like the idea of getting 5V from the PC because then it becomes a specially modified PC. Would rather put a dedicated 5V supply into the control box. The toroid guys might be able to give us a transformer output to start with....? |
James Webster
Registered
Username: Wti
Post Number: 21
Registered: 02-2007
| | Posted on Saturday, March 03, 2007 - 11:08 am: |
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I'm sure John at http://toroid-transformer.com would add an extra winding if enough people asked for it (some hacker types might just wind some wire around the existing toroid and "steal" away 9-12v).
To make a regulated supply, we would need more volts to start with (thus the 9-12v tap from the transformer, or a "wall wart", because the regulator needs about 3 more volts coming in than going out), a voltage regulator (LM 7805), a heat sink (that's where the extra volts get dumped), a 100uf cap across the input and a 10uf cap across the output (to smooth things out). I can draw a picture if anyone needs one.
But for all of that trouble, every desktop computer already has a regulated 5v supply on the extra hardrive connectors. The red wire is 5v the yellow is 12v, the blacks are grounds. So the only modification is to buy a $1 connector and run a cable out the back (or get really fancy and put a jack on the back).
 |
James Webster
Registered
Username: Wti
Post Number: 22
Registered: 02-2007
| | Posted on Saturday, March 03, 2007 - 11:25 am: |
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Thinking more about this, the only reason (and this may be of no importance in the real world) to maybe use an outside power supply is that the ncPOD will finish the job even if the computer crashes (that is what the memory card is for).
So if the computer crashed so hard that it rebooted, the power would be cut for a second.
Again, I don't know what the chances of a computer rebooting while cutting are, but I have seen them crash and snooze.... |
Gerald_D
Registered
Username: Gerald_d
Post Number: 1086
Registered: 11-2005
| | Posted on Saturday, March 03, 2007 - 11:25 am: |
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James, you describe the easy part of the story..getting 5V out of a PC. But, how do you get that thin cable into the control box and where do you connect the ground wire to avoid ground loops?
John does do neat little 5V 9V oops regulators off his toroids - link
(I forgot about stealing off the toroid (last did that in 1975!)) |
Mike Richards
Registered
Username: Richards
Post Number: 71
Registered: 05-2006
| | Posted on Saturday, March 03, 2007 - 11:59 am: |
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Here's a simple schematic for those who want to build their own 5VDC power supply.
All of the components can be of the "junk bin" variety. The transformer should be at least 6VAC but not more than 8VAC with a current capacity about 2X what you need (to keep heat down). The output voltage will be 1.41 times the transformer's rated voltage. So, a 6.3V transformer will give you about 8 or 9 volts DC. The voltage regulator needs at least 7 volts unregulated DC before it can supply 5VDC. Remember though, that too much voltage also means too much heat. The bridge rectifier can either be four diodes or a small bridge. Use components that have at least 2X the rated current to keep heat down. The minimum voltage rating on most diodes and bridges is 50V, so almost any voltage rating should work. C1 is a smoothing capacitor, so 220uf to 470uf is adequate for small power supplies. This capacitor takes most of the ripple out of the circuit. As long as there is at least 7V available to the voltage regulator, you should get a steady 5V out of the regulator. R1 is an optional 1/2-watt 100-ohm bleeder resistor. It drains power from the capacitor when the power is turned off. The 7805 is a TO-220 or T0-3 voltage regulator. A T0-220 can output about 1-amp. A T0-3 size can output about 3-amps. Use a heatsink and heatsink grease. C2 is a small electrolytic filter capacitor rated at about 10uf. I always use a fuse to protect the power supply 'just in case'. Total cost for the components should be less than $20. |
James Webster
Registered
Username: Wti
Post Number: 23
Registered: 02-2007
| | Posted on Saturday, March 03, 2007 - 12:00 pm: |
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If one wanted a pre made supply, I'm sure John could add a 5v regulated output circuit. He might in the long run make a Mechmate model if the demand was there.
The USB cable has its own ground and shield (and even 5v, but I guess, not enough amps for us to use) inside of it.
I fired off an email to John at Oemtech for a no guess answer. |
Gerald_D
Registered
Username: Gerald_d
Post Number: 1087
Registered: 11-2005
| | Posted on Saturday, March 03, 2007 - 01:45 pm: |
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....and I sent a mail to John at http://toroid-transformer.com to see if he wants to do a MechMate supply broadly to this spec:
- 300 or 500 VA
- 50 or 75V DC out (after rectifier) unregulated 10000 to 15000 MFD cap
- 5V 500mA regulated
- Occupy a cubic space - transformer sets footprint, caps & regulator above. Or, like this example:
http://www.mechmate.com/Forum/messages/17/670.html. Generally a smallish footprint, but 6" tall is okay.
Edit: John's great reply!
(The last few posts might find another home in a power supply thread later - the 5V supply can be useful for the nominated PMDX-122 as well.) |
Gerald_D
Registered
Username: Gerald_d
Post Number: 1092
Registered: 11-2005
| | Posted on Saturday, March 03, 2007 - 08:49 pm: |
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Mike, what do you think of turning some wire through the toroid (DIY-ourselves) to power the PMDX-122 directly into its 9V AC input option? |
Mike Richards
Registered
Username: Richards
Post Number: 73
Registered: 05-2006
| | Posted on Sunday, March 04, 2007 - 05:21 am: |
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Gerald,
I'm sure that would work. So far, I have never wound a toroid, so all I know is what I've read. The difficult part would be knowing how many 'turns' to wind. I suppose that you could wind a dozen turns, connect a meter to the new turns, turn on the power, and see if there is any voltage. Assuming that there would be some reading on the voltmeter, it would just be a process of turning off the power, and winding some more turns until you had the desired voltage.
(There are a number of warnings about keeping the windings tight, using tape, etc. on various web sites. I have no idea whether they're valid or not.) |
Gerald_D
Registered
Username: Gerald_d
Post Number: 1097
Registered: 11-2005
| | Posted on Sunday, March 04, 2007 - 05:47 am: |
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It is 5:45am coffee time here now - day is breaking. Looks like a little experiment is called for today.....
(James Webster reminded me of this option) |
Gerald_D
Registered
Username: Gerald_d
Post Number: 1100
Registered: 11-2005
| | Posted on Sunday, March 04, 2007 - 11:15 am: |
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Grabbed a 500VA toroid, looped 12 turns of wire, and got a steady 6.6V from it. Havn't got long enough thin insulated wire here at home, but it is very obvious that this is an easy option to power a PMDX-122. The little grey block transformer I am using now is nominal 9.5V, but actually puts out 11.5V no load because the magnetic core is so minimal. Winding around the huge toroid will be much better than a separate small transformer....and it solves mounting and space problems. |
Gerald_D
Registered
Username: Gerald_d
Post Number: 1101
Registered: 11-2005
| | Posted on Sunday, March 04, 2007 - 11:36 am: |
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When I bought that little no-name brand 9V transformer, I had this discussion with Steve Stalling at PMDX:
I have just learnt that a nominal 9V transformer in the 2VA range has an off load voltage of about 1.35 times higher than when fully loaded. I was going to ask for a better transformer this morning, after measuring 11.4V at the output terminals, and 11.2V when connected to a "naked" (nothing connected) PMDX-122. The sales guy hauled out a couple of supplier's data sheets and showed me that this behaviour is typical for transformers in this range.
Can I carry on using this transformer?
The 8 - 10 VAC supply should work OK. We had allowed
lower voltage supplies earlier and most worked, but a
few were weak, so we said 9 VAC. Greater just creates
a bit more heat in the regulator. We didn't want people
using 12 VAC, so that left 9 VAC as the only commonly
available value. |
James Webster
Registered
Username: Wti
Post Number: 25
Registered: 02-2007
| | Posted on Monday, March 05, 2007 - 07:51 pm: |
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Carl at Oemtech just emailed us back and said it would be "just fine" to take 5V off of a spare hardrive connector and power the ncPOD with it. |
Gerald_D
Registered
Username: Gerald_d
Post Number: 1112
Registered: 11-2005
| | Posted on Monday, March 05, 2007 - 08:20 pm: |
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I would still be concerned about the potential ground loop from a remote power supply in the PC's case. |
70. Control Systems