Messages

331

General Mach Discussion / Re: Can someone explain how a capacitor acts as a filter?

« on: July 07, 2012, 07:36:40 PM »

Very clear, thank you for the analogy. One question though, would using a smaller capacitor have the same effect as using a smaller water tank, given the analogy? Reason I ask is I'm trying to filter noise on some encoder inputs. I have 1uF caps but the delay in the encoder getting the signal to the computer is too large and causing inaccuracies. Would a smaller cap reduce the delay?

Way back I learned all about capacitors and such things of the electronics world, but when you don't use it frequently, the information tends to fade.

Yes, for an encoder, you need to use something fairly small, typically 0.01uF or 0.001uF.

Regards,
Ray L.

332

General Mach Discussion / Re: Can someone explain how a capacitor acts as a filter?

« on: July 07, 2012, 03:33:39 PM »

Easiest to understand as a water analogy.  Pretend you have a hose, with water flowing through it.  The water pressure is the equivalent of voltage (basically how hard it's "pushing"), while the flow-rate is the equivalent of current (the volume of flow).  Now suppose some wise guy is playing around, and periodically pinching the hose, interrupting the flow.  If you're trying to use the hose, you'll see the flow interrupted every time he puts this thumb over the end of the hose, and you'll see flow, no flow, flow, no flow.  Now suppose you instead run the hose into a big tank, and take your water from a faucet at the bottom of that tank.  Now when the bozo pinches the hose, your flow probably won't be interrupted, because there will be enough water in the tank to provide some flow, as long as the hose is not pinched for too long.  So, the tank "filters" the water, preventing you from seeing short interruptions in the supply.  That is precisely what a capacitor does - it stores charge, not water, but filters in precisely the same way as that tank.  If there is a disturbance (noise) on the input signal, the output signal will be maintained by the charge in the capacitor for a short period of time.  Only longer, or very frequent, noise will get through.

Regards,
Ray L.

333

General Mach Discussion / Re: DRO#s in WIZARDS

« on: June 24, 2012, 11:48:14 AM »

Wizards would be basically useless with people from all over adding to the general mess IF all of them drew from the Dro global pool.  HOw would everyone keep track of the useage???

Terry,

Well.... that's exactly the situation you have with macros and DROs, so I don't see any difference.  It's a shame they didn't think to provide a means of allocating DROs and other resources at run-time, so you could be guaranteed no conflicts.  Right now, it's just a free-for-all, which is bound to run into trouble sooner or later, especially since there are not even any guidelines on DRO usage - like defined (recommended) ranges for macros, wizards, etc.  Not that anyone would follow such guidelines anyway....  So many things in Mach3 are handled like the Wild West - where possession is 9/10ths of the law.

Regards,
Ray L.

334

General Mach Discussion / Re: X-Y offset in tool change? Macro?

« on: June 23, 2012, 09:58:51 PM »

Anyone out there that uses a similar system? It is not make multiples of the same part using an offset, but using different spindles to work on the same part.

I have another CNC with a tool changer, so I hope to be able to use the same g-code. So the whole procedure of switching spindles and automatically changing the XYZ offset should be triggered by one simple tool change command. I figure that a decent tool changer can't be found for less than 5K, an extra spindle for boring only, can be build for a few hundred.

Stefan V

You've been given two very simple ways of doing what you need.  What more are you looking for??

Regards,
Ray L.

335

General Mach Discussion / Re: DRO#s in WIZARDS

« on: June 23, 2012, 07:13:43 PM »

Terry,

AFAIK, DROs are a single, global pool.  If ANY two scripts, plug-ins, wizards or whatever use the same DRO number, they will step on each other.

Regards,
Ray L.

336

General Mach Discussion / Re: X-Y offset in tool change? Macro?

« on: June 23, 2012, 03:38:50 PM »

G54-G59 fixture offsets will do exactly what you need.

Regards,
Ray L.

337

General Mach Discussion / Re: IF you could add new Gcode functions to Mach3 what would you want?

« on: June 14, 2012, 09:08:26 PM »

I'd be happy if the existing G and M codes simply did what they were supposed to, first time, every time.  That has been my single greatest joy since switching to the KFlop - it is 100.000% reliable and consistent.  It has not screwed up, even a tiny bit, one single time in the last 5 months!  When the machine does something wrong, I KNOW it's because I programmed it wrong, and not that the program did not execute correctly.

Regards,
Ray L.

338

General Mach Discussion / Re: While Ismoving() Wend

« on: June 12, 2012, 10:46:56 AM »

Terry,

I though Brian had changed the Code() operation, perhaps two years back, so that it would wait for the command the complete before returning, making the While/Wend unnecessary?  Am I remembering it wrong?  I seem to recall he added some other function to just buffer the command and return immediately.  IIRC, this was done at the request of Dave Bagby for MSM.

Regards,
Ray L.

339

General Mach Discussion / Re: Gcode Viewer

« on: June 07, 2012, 11:26:42 PM »

Terry,

Shoot me an e-mail.  I've got a nice one I can send you - it's what I use in the KFlop CNC Controller I wrote.

Regards,
Ray L.

340

General Mach Discussion / Re: Newbie Help Please with Tool Offsets

« on: June 07, 2012, 05:47:10 PM »

I believe only LazyCAM Pro does offsets.  For the free version, you need to draw the toolpaths appropriately offset for the tool you will use.  All the common "hobby" CAMs (SheetCAM, CamBam, etc.) will to proper offsetting.  LazyCAM is *really* bad.  And don't even get me started on LazyTurn....

Regards,
Ray L.