Messages

131

General Mach Discussion / Re: BT30 spindle from scratch - with power drawbar and ATC of course

« on: January 20, 2013, 05:57:37 PM »

If anyone's interested,Ive just made power draw bar for my tool changer,used a stack of belvilles,a 20mm spring collet ala tormach.
 To power it I used 2  50mm dia 20mm stroke air cylinders in parallel,with a bar joining the 2 piston rods, that in turn operates on a pivoted crank arm giving a 3-1 advantage,its got loads of power I can plough a 18mm dia ripper 10mm deep through ali at 250mm pm no problems no slip, good enough for me and most folks I guess ?

My first attempt was a large stepper with a 1.5mm pitch lead screw operating the 3-1 lever I had micro switches, and a logic circuit controlling it.All i can say is it cost me a fair amount of time and money and never really worked reliably, and even with all that mechanical advantage it never really had the grunt.I would advise from my own experience don't go down that route!
 

Tony

132

General Mach Discussion / Re: unwanted creep in jog mode?

« on: January 17, 2013, 05:56:47 PM »

dont know if you remember but i had timing issues and at the set kernal speed the actual and reported feedrates are closest,i havnt had any issues with unreliability at these setting.

133

General Mach Discussion / Re: unwanted creep in jog mode?

« on: January 17, 2013, 05:31:15 PM »

OK finaly got to get the xlm, dont think the answer lies there,as ive used the same one roughtly for a few years,it is a new(to me) computer,I use a ps2 keyboard (cherry) and a dell usb mouse,other than the pendant, Remember it hapens in mpg mode not continuos,using the pendant.

oh and the creep is on the axis you used last,i.e. if you wind the x axis it carries on creeping

134

General Mach Discussion / Re: unwanted creep in jog mode?

« on: January 16, 2013, 03:46:48 AM »

tweaky, thinking about it this has only started since i put a cheap chinese usb button pendant on,which i would like to continue to use cos its so usefull, ill try your solution but as its random i doubt i'll have a quick answer. Hood, Yes it was just too cold here just south of birmingham (worcester UK) even colder today!

    Tony

135

General Mach Discussion / Re: unwanted creep in jog mode?

« on: January 15, 2013, 02:48:01 PM »

Sure ill brave the cold and nip out to the garage and copy it!

Tony

136

General Mach Discussion / Re: unwanted creep in jog mode?

« on: January 15, 2013, 02:00:13 PM »

Do the DROs in Mach reflect the movement?    Yes
Do you have in step mode when using MPG?   No
Do you have a fairly low acceleration set for the axis?    No

hope that helps

137

General Mach Discussion / unwanted creep in jog mode?

« on: January 15, 2013, 08:36:45 AM »

Hi my mach3 set up has developed a strange fault,occasionally while jogging (i have 2 mpg's fitted) an axis will creep on continuosly without having the handle turned? and it will carry on creeping at about 30mmpm until you hit reset. it is random apart from it generally happens when you have been doing alot of jogging,ie setting up,I have actually broke a couple of tools now so any help will do.
  thanks
    Tony

138

General Mach Discussion / Re: 6 axis robot arm thoughts.

« on: December 09, 2012, 08:13:06 AM »

ger 21,
  no id probably go 4/1 belts all round,plus as i said mach to drive some other system interfaced with the encoders purely for recording the pulses.

139

General Mach Discussion / 6 axis robot arm thoughts.

« on: December 09, 2012, 06:04:50 AM »

Hi, im thinking of building a 6 axis robot arm.using nema 23 425oz steppers.
I am assuming mach3 will control it. Its for trimming vacuum formed plastic parts.
  What im thinking about is using the steppers on 1/2 step mode and bolting 100ppr encoders on the back of them,(giving 400 pulses per rev)
 I would like to do is then manipulate the arm by hand and record the pulses,which could then be somehow turned into machine commands, and replayed as a program.
Is this a goer or a non-starter? any thoughts?
    Tony

140

General Mach Discussion / Re: USB pendant button association ?

« on: November 23, 2012, 07:27:09 AM »

got it sorted screen 4 is cleverer than I thought