Author Topic: Chester 626 mill CNC Conversion  (Read 269510 times)

Offline Swarfing

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Re: Chester 626 mill CNC Conversion
« Reply #50 on: October 04, 2011, 04:50:13 PM »
I really do think this a bad idea? having the coupling fixed with a grub screw allows something to give when a lockup happens. Threading this coupling on will allow something more expensive to crap out, 5p grub screw verses £100 ballscrew?
Once in hole stop digging.

Offline John Stevenson

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Re: Chester 626 mill CNC Conversion
« Reply #51 on: October 04, 2011, 05:20:46 PM »
I really do think this a bad idea? having the coupling fixed with a grub screw allows something to give when a lockup happens. Threading this coupling on will allow something more expensive to crap out, 5p grub screw verses £100 ballscrew?

Not so, I have driven plenty of screws hard onto stops, all that happens is the motor stalls.
Only machine I had a problem with was my big CNC when I had a job over hanging the back of the table, big set of V twin flywheels. because the flywheels hit the casting before it was anywhere near the limits it sheared the flexible element inside the Oldham coupling.

Never had any of the smaller machines shear a coupling element.
Another reason I like Oldham couplings, if the element goes it looses drive, if a Lovejoy smashes the flexible coupling the metal parts will still drive.

John S.
John Stevenson

Offline Swarfing

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Re: Chester 626 mill CNC Conversion
« Reply #52 on: October 04, 2011, 05:58:32 PM »
See what you are saying, my brain is quite dead tonight so agree whole heartedly :doh:
Once in hole stop digging.

Offline John Stevenson

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Re: Chester 626 mill CNC Conversion
« Reply #53 on: October 04, 2011, 06:06:11 PM »
Little know fact is the Oldham coupling was invented by an Irishman called John Oldham to get by a problem they had with paddle steamers.
if they hit a submerged log the force was enough to break a drive shaft or paddle which meant the steamer was out of action for quite a while.

By fitting an Oldham coupling with iron or steel sides and a wooden element when they hit a log it sheared the coupling and all they had to do was slide one coupling to one side, insert a new disk and reset the coupling.

So next time you cram  the table onto the stops remember to throw a lifebelt after it.  :lol:
John Stevenson

Rob.Wilson

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Re: Chester 626 mill CNC Conversion
« Reply #54 on: October 05, 2011, 01:40:07 PM »
Good bit of trivia John  :med:

the Oldham coupling was also used  on some models of traction engines , Tasker ,Fowler .


Rob  

Rob.Wilson

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Re: Chester 626 mill CNC Conversion
« Reply #55 on: October 16, 2011, 09:24:08 AM »
A wee bit more progress  :zap:

I had a lump of 1/4 thick ally plate 18 x24 lying round the shop , that i had taken out of some machine somewhere back in time thinking it would come in handy some day   :med:  , just the job to mount the drivers, PSU's and breakout boards too  :dremel: space left for fourth axis (one day )
 

Still a bit more wiring to do ,,,,I now have the motor i am using to test  spinning after lots of arse scratching ,, the manuals leave ALLOT  to the imagination , breakout board settings for mach3 that are in the manual dont work and missing driver info  :coffee: 

Rob   

Offline doubleboost

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Re: Chester 626 mill CNC Conversion
« Reply #56 on: October 16, 2011, 04:58:27 PM »
Looks great rob
All you need now is a

BIG START BUTTON
:bugeye: :bugeye: :bugeye: :bugeye:
then it will be making bits :D :D :D :D :D

Offline John Swift

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Re: Chester 626 mill CNC Conversion
« Reply #57 on: October 17, 2011, 10:56:26 AM »
Hi Rob

I've been watching your inspirational project

if you have not solved the Mach 3 settings for the board

what info do you have for the breakout board?

 a table showing the function of the printer port pins ?

   John

PS is this any help ?

Rob.Wilson

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Re: Chester 626 mill CNC Conversion
« Reply #58 on: October 17, 2011, 12:30:52 PM »
Hi Rob

I've been watching your inspirational project

if you have not solved the Mach 3 settings for the board

what info do you have for the breakout board?

 a table showing the function of the printer port pins ?

   John

PS is this any help ?


Hi John  :wave:


I have sorted the first breakout board inputs and out puts ,, and all configured in Mach3 ,, Estop,Home switches and all motor spin .

Its the second breakout board (the one in the photo with nowt plugged into it )  inputs and out puts for the hand controller ,,, i have the same drawing as you witch shows the connections to the 15 pin plug ,,,, but what pins do they correspond to on the 25 pin plug  :scratch:   ,,,,, first i need to fined out what pins  are inputs and  outputs on a second  PP card .


Chers Rob   

Offline John Swift

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Re: Chester 626 mill CNC Conversion
« Reply #59 on: October 17, 2011, 01:41:59 PM »
Hi Rob

what are the two large IC's ?  I expect the 3 others are 74LS14 hex inverters  (can buffer 18 signals )

just looking at the table  I'd expect the step and direction siglals  from the computer and hand control are OR'ed together in pairs

step and direction signals

PC       remote
25w = 15w
    2 = 6
    3 = 13
    4 = 1
    5 = 3
    6 = 11
    7 = 4
    8 = 12
  14 = 7
  18 = 5
  17 = 2

 25w pin1 = enable for all motors ?  15w pins 8 , 14 ,15 could enable  the motors , or may be one enable the spindle ?
25w pin 9 =spindle relay could be 15w pin 8 , 14 or 15 if remote can switch the relay ?

I guess one possibility is the enable signals from the remote could be pin 8 = printer port pin 1 = motor enable
remote pin 14 switch control to the remote control and pin 15 enable = switch on the spindle

   John

PS    do you have a link to the remote controle you have ?
       its possible the breakout boards are  for the simple hand control used with the TB6560 boards
       and are  not correct for your remote control
« Last Edit: October 17, 2011, 02:10:22 PM by John Swift »

Rob.Wilson

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Re: Chester 626 mill CNC Conversion
« Reply #60 on: October 17, 2011, 02:28:09 PM »
HI John

Now that sounds logical ,,, just need to test it,,,, any ideas  :scratch:  ,,,,,,,,,,,the two larger chips are  74HC244D  .....three smaller ones are 74HC14D hard to read ,, me thinks i need specs  :lol: :lol:

couple of photos of hand control



way way to many wires sprouting from it  for my liking  :lol: :lol:



Rob

Offline John Swift

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Re: Chester 626 mill CNC Conversion
« Reply #61 on: October 18, 2011, 10:47:40 AM »
Hi Rob


if you power the manual pulse generator from a usb port  ,
you may be able to connect the switches directly to the second printer port ,with pins 2 to 9 programmed as inputs

(or via a 56 ohm resistor, this  would limit the current if your switch grounds a pin that is  an output at  +5V !!)



better still  another  breakout  board using two  74hc245 octal buffers that can be switched to give you more inputs on pins 2 to 9


you need to set up mach 3 to use the A & B manual pulse generator outputs ,pins 3 & 4  (or inverted A & B  outputs, pins 2 & 5  )


the switches need to go to input signal pins programmed as OEM trigger    (I think ,now I've downloaded the mach 3  manual ! )

not sure what voltage the LED indicator is for , the resistor value is not readable in your diagram


I think I'd connect the E STOP button in series with another  lowvoltage STOP switch  on the machine and not use it via the printer port


 

     John

 just had a look at the limited info for the TB6560 boards and on the 15w D type connector they have used
pin 14 for GND and pin 15 for +5v

link --   http://www.ebay.co.uk/itm/Handle-Controller-FR-TB6560-5-Axis-Stepper-Motor-Driver-/220859461910?_trksid=p3286.m7&_trkparms=algo%3DLVI%26itu%3DUCI%26otn%3D3%26po%3DLVI%26ps%3D63%26clkid%3D3567783428599467203


the long white connectors on you breakout board is for this type of display -
http://www.ebay.co.uk/itm/320762884378?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2649
« Last Edit: October 18, 2011, 02:05:25 PM by John Swift »

Rob.Wilson

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Re: Chester 626 mill CNC Conversion
« Reply #62 on: October 18, 2011, 12:59:28 PM »
Hi John

Cheers for the wiring diagram  :beer:  ,,,,,,, I was planning on using P9 5V and P10 G  on the 15pin connector on the second BOB to run the MPG , do you think that would work ?

Yes your correct the switches need to be configured in Mach3 ,,,,, i have a list of OEM codes that Mach uses for external switches.

Looking at the board all the 25pin connections have a 56 ohm resistor fitted to them already  :thumbup:


Cheers Rob   

Offline John Swift

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Re: Chester 626 mill CNC Conversion
« Reply #63 on: October 18, 2011, 01:27:52 PM »
Hi Rob

the only picture of your breakout boards I've found is an advert for the  TB6560 boards

I'm not convinced it will let you use printer port pins 2 to 9 as an input into the PC

but the 15 way D type connector does have a +5v supply for the simple "blue"control sold for the boards

I'll see if I can find out which pin

for you initial test just connect the switches to see if the breakout board will let the PC detect  the switches
and not the manual pulse generator

   John

PS   ---  just looked at the limited info for the 15 w D type connector as used on the TB6560 boards and they have used
             pin 14 for GND and pin 15 for the +5v to the "blue" remote control

link --  http://www.ebay.co.uk/itm/Handle-Controller-FR-TB6560-5-Axis-Stepper-Motor-Driver-/220859461910?pt=LH_DefaultDomain_0&hash=item336c3ff116


the long white connector on your breakout board is for a display like this

http://www.ebay.co.uk/itm/320762884378?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1438.l2649link   --  

« Last Edit: October 18, 2011, 02:10:01 PM by John Swift »

Rob.Wilson

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Re: Chester 626 mill CNC Conversion
« Reply #64 on: October 20, 2011, 01:20:37 PM »
 :doh: well the second breakout board is no good for the job at hand  :coffee:  no connection's between the 15 and 25 plugs  :doh:
so i need a plan B  :med: ,,,,,,,, So i rigged the hand control up to the inputs i had left on the two BOB,s just to test some set-ups.
boring video , really crappy camera work  

Rob
« Last Edit: October 20, 2011, 04:55:52 PM by Rob.Wilson »

Offline John Swift

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Re: Chester 626 mill CNC Conversion
« Reply #65 on: October 20, 2011, 02:36:34 PM »

Hi Rob

just an initial idea for a DIY breakout board using two 74HTC245 IC's and vero board

the 56 ohm resistors are optional

so I've not found somewhere that sell an old style of D-Type connector that is ideal for use on veroboard

the 25 way plug will only need one wire to GND with pin2 1 to 13 connected directly to the board
but the 15 way D-type will need 6 wires for pins 9 to 15

   John


Offline Bluechip

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Re: Chester 626 mill CNC Conversion
« Reply #66 on: October 20, 2011, 02:42:02 PM »


Hi Rob

just an initial idea for a DIY breakout board using two 74HTC245 IC's and vero board

the 56 ohm resistors are optional

so I've not found somewhere that sell an old style of D-Type connector that is ideal for use on veroboard

   John



Like these ??? Or not the same/similar ???

http://www.rapidonline.com/Cables-Connectors/Right-angle-39-D-39-connectors-63708

BC


I have a few modest talents. Knowing what I'm doing isn't one of them.

Offline John Swift

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Re: Chester 626 mill CNC Conversion
« Reply #67 on: October 20, 2011, 02:55:19 PM »

Hi Dave BC

for a printed circuit board the connectors from rapid are OK
 but the ones in my picture are better for veroboard
because you can bend the long pins from the top row to fit the 0.1" grid
the solder tag version is the alternative I'm likely use ?

        John

Rob.Wilson

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Re: Chester 626 mill CNC Conversion
« Reply #68 on: October 20, 2011, 03:05:52 PM »
Cheers John ,,,,,,,,, Now that looks like a great plan B  :thumbup:


Cheers Dave ,,,,, looks like i better setup an account with Rapid  :headbang:


Just an idea ,, i could have the 25 pin on a lead and fix it so it comes through  the side of the  enclosures    :zap:, it would make it easier to hook the computer up .



Cheers lads Rob     :) 

Rob.Wilson

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Re: Chester 626 mill CNC Conversion
« Reply #69 on: October 20, 2011, 03:16:15 PM »
Hi John


What are the two capacitor values ?    ,,,,,,,,,,,,,,,,, is it better to have the resistors ?


Rob

Offline John Swift

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Re: Chester 626 mill CNC Conversion
« Reply #70 on: October 20, 2011, 03:26:47 PM »


Hi Rob


sorry its a bit too small on the diagram but any thing around 0.1uF will do

If you use ribbon cable you can place both connectors on the side of the enclosure
IDC  D-types and IC headers could make the connections easier

how are you going to use the stop switch ?

      John

Rob.Wilson

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Re: Chester 626 mill CNC Conversion
« Reply #71 on: October 20, 2011, 03:45:17 PM »
Hi John

cracking diagram  :headbang: just printed it off .

I think i have a header cable some were , plan gets better .


the  E stop i will connect across to the first BOB E stop pins .

Just need to fined some 74HCT245 chips ,,,,,,, was hoping maplins would have them ,,,,,but they dont  :(


Rob

Offline John Stevenson

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Re: Chester 626 mill CNC Conversion
« Reply #72 on: October 20, 2011, 04:20:46 PM »
Rob,
RS have them  156-9803

Check your email.
John Stevenson

Offline Bluechip

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Re: Chester 626 mill CNC Conversion
« Reply #73 on: October 20, 2011, 04:23:24 PM »

Just need to fined some 74HCT245 chips ,,,,,,, was hoping maplins would have them ,,,,,but they dont  :(


Rob

MAPLINS ....   ??? ::)    :lol:  :lol:  :lol:  :lol:  :lol:  :lol:  :lol:

Did you check Tesco's while you were fantasising  ???

I only have 17, but they are 74HC245's ...

Want some ???


BC
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Offline John Swift

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Re: Chester 626 mill CNC Conversion
« Reply #74 on: October 20, 2011, 04:26:12 PM »

Hi Rob ,

the circuit can be rearranged to use the 74HC541 that maplin have cat no UB93B but it looks like you have to order it

     John