Messages

1

General Mach Discussion / MPG issues

« on: December 14, 2013, 06:14:57 PM »

Hopefully someone can help me.  I purchased three MPG wheels off of ebay so that I can use my mill like a manual for small jobs and I thought it would be quite cool.  I tried out and got strange results.  
The MPG wheel is a 100 detent type that works from a 5v supply and on the back of the wheels are six terminals, + -, A B A- B-.  

So, with a wheel connected its own 5v supply unit I wired up the A and B terminals to two spare input terminals on my C11G board which runs through a smooth stepper.  The input indicator led's flash one after the other depending on the direction so I took that as a good sign.  I setup the ports and pins as per normal and ran through the MPG config and got 4 pulses per indent, clicked save etc.  I set the Jog settings to multi step and set the resolution to 1thou.  Now when I turn the wheel in one direction it misses a few indents and doesnt turn the required amount, when I turn the other way it hardly moves at all, missing entire turns and then twitching.  

It does seem to get a signal to mach 3 as it will move the motors but its extremely erratic and not really useable.  So, im assuming that it is a software problem.  I tried running this through my direct input board to the smooth stepper with exactly the same result.  

Can anyone with a similar unit let me know what their settings are that may affect the operation of the wheels, Mach3 runs great in every other respect.  In the ports and pins settings it says 4 yet this can be changed and doesnt seem to relate to the MPG config.  How hard can this be....

2

Sieg Machines / C3 index pulse board with three optical switches in series...

« on: August 13, 2013, 01:57:41 PM »

Hey all, I wonder if someone can help me. 

I thought I would be cheeky when setting up my optical slot homing switches on my sx3 and use them connected in series to cnc4pc's C3 index pulse board as I had this wired up already from the lathe set-up.  I was able to get two up and running but whenever I connected the third in series it wouldn't work.  Now, I am not up to date with electronics so unless it's obvious im at a loss.  Any ideas?  I'd rather not have to buy another interface board unless it was cheaply priced.   

Thanks, Rob.

3

Show"N"Tell ( Your Machines) / Many many inputs

« on: June 13, 2013, 07:41:56 AM »

Hey all,

Im well on the way to building my SX3 CNC mach based machine.  As this is my only milling machine I wanted to be able to use it as a manual machine too, so after looking on ebay I got three chinese mpg wheels and have made some mounting brackets.


I am also making my control unit in a computer box to keep everything tidy.  I plan to fit a 4th axis driver soon too.


But, this requires two inputs per axis plus some other switches to control x10 x100 etc so my question (whilst showing progress) is: are there any opto-isolated breakout boards which favour inputs over outputs i.e. I want as many inputs as possible, that work with a smooth stepper and mach3 and are cheap......

When I get some more time I will post the progress leading upto this point.

Rob.

4

FAQs / Help with Turn R2.0.053 Spindle Pulley Ratio location

« on: October 01, 2010, 11:08:18 AM »

Hey all, just a quickie.  I currently have Turn R2.0.053 and for the life of me cannot find the spindle pulley ratio box.  Any ideas where it could be would be great.  Its not on the spindle pulleys tab under config and yes my spindle is working on M3 and M4 commands but is out due to the ratio. 
Help would be great.

Rob.

5

General Mach Discussion / Re: Automoatic tool changer macros & sensing

« on: September 29, 2010, 07:17:13 PM »

It's easy once you know 

Right, nows the time to learn some visual basic.  I will take the two examples provided and have a play although I cannot really do much until my ATC driver appears which is annoying.  I will have a look at some of the visual basic tutorials tomorrow too.  It can't be that difficult, can it? 

Rob.

6

General Mach Discussion / Re: Automoatic tool changer macros & sensing

« on: September 29, 2010, 02:40:07 PM »

Thanks for that macro, although I must download something to view them properly as I'm using notepad and its all in a single string - not easy to read at all (as you can tell, haven't even thought about macro's until 4 days ago). 

I'm all electrically hooked up now except for my stepper driver which was deemed 'out of stock' this afternoon
This is what my new cable looks like inside : (i have used 20 core video cable and tripled the wires for the stepper - its nice and flexible and screened too)


An aluminium adapter plate was made a tad less than 1/4" thick.  The spindle of the stepping motor is 6mm and locates in the hole of the worm wheel shaft which seems to be smaller than 1/4" by a tad (drill blank wouldn't go in).  A 3/32 hole was made through the motor spindle 1/8" from the end and a cross pin pressed in.  This locates in the slot in the end of the worm wheel shaft.  This pin has to be fairly accurately drilled. 


This board operates on 12v, so three 12to5v DC-DC converters were used to step down the output signal voltage to a high of 5.1v and a low of 0.8v when measured with a multimeter.  These outputs were then connected to pins 11, 12 & 13 on the C11G and mach reads them without a problem. 


All i need to do know is get my head around Macros and make an efficient program.  Tis all good fun  

7

General Mach Discussion / Re: Automoatic tool changer macros & sensing

« on: September 27, 2010, 07:36:06 PM »

Hmm, that was a good read and gives me my starting point.  I will have to learn how to write a macro me thinks!  Thanks allot hood, always very helpful.

Im hoping to use the signals generated by the three sensors to give it its position, for example have a table stating that if 1,1,0 is active then for tool number * it must rotate so many steps then reverse 10.  It may be a long macro but it should work well as long as i can get it to read the input signals. 

Can anyone recommend me a cheap, preferably UK based break out board that would be suitable just for this purpose and maybe a few relays for other things as I have a second parallel port. 

 Rob. 

8

General Mach Discussion / Re: Automoatic tool changer macros & sensing

« on: September 27, 2010, 12:24:11 PM »

Hood, I salute you sir.  I really want to get all the machining/mechanical stuff done before I go back to uni next week as the wiring/computer stuff can be done in my room. 

Rob.

9

General Mach Discussion / Automoatic tool changer macros & sensing

« on: September 27, 2010, 11:57:02 AM »

Hey all,  I have recently been playing with my new toy - a denford orac which i have fitted with a C11G and index pulse board from CNC4PC driving  two gecko 201's and it works great

My new set-up in a PC case:




It also came with an automatic tool changer and three burnt out dc motors to operate it.  They rattle, whine and burn out as they are used to keep the ratchet against its pawl in 12v reverse mode.  Well, I have fitted a small stepping motor to it with the idea that using the grey code that the 3 sensors produce with its reflective disk, it could tell where it is, rotate a set number of steps for the tool change (it operated a work at 40:1) and reverse a small amount onto the pawl, skipping a step or two and then hold. I was going to use a small cheap driver such as this http://proto-pic.co.uk/products/EasyDriver-Stepper-Motor-Driver.html.  Is this an ok idea? and can someone please give me an idea of how to write a macro for it.  I can build a system, do gcode etc but macro's scare me.  I have no idea if the greycode produced by the sensors can be used???




denford sensor drawings:

http://www.denfordata.com/bb/download/file.php?id=598
http://www.denfordata.com/bb/download/file.php?id=597

Any help would be amazing

Rob.

10

General Mach Discussion / Re: Complete Gcode List

« on: September 25, 2010, 05:06:18 PM »

Ah I see.  

Thanks for letting me know, I would've had no hair left trawling the forums and internet trying to find something.  My impression is that cnc turning is slowly becoming more popular so hopefully it will get some more attention.  


A friend of mine got into mach3 at the same time and even though there is a 45 year difference and this is his first computer - he is doing amazingly well.  I have started doing small instructions for me and him so that we know how to do stuff.  A link is shown here:
https://docs.google.com/document/edit?id=1ERUquEj66EbYI_Punsd-JX6ONqe-Ew6aarzcug-wQ74&hl=en&authkey=CIGcqOgM
It would be great if i could get some others done as well and if people want to share their codes to make life easier all the better  

Oh, also, when using metric feed/rev mode - is there anyway of allowing the feed increment to use a decimal point.  If im doing 0.2mm/rev and want to change it quickly, the smallest increment i can make without having to uncover the keyboard is 1 and 1.2mm/rev is quite large.  

Rob.