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Pete92
30-09-2013, 11:41 PM
Right, I have bought a EMCO Compact 5 Mk1. I want to convert it to run Mach3 or similar program.

What I would like to know is where to start?

Do I need homing sensors on the axis?
Where about on a control board would I wire in the rotary encoder off the spindle.

If anyone has any experience on doing thing advice would be much appreacted.

Google Image Result for http://reprap.org/mediawiki/images/e/e9/TB6560.jpg (http://www.google.co.uk/imgres?imgurl=http://reprap.org/mediawiki/images/e/e9/TB6560.jpg&imgrefurl=http://reprap.org/wiki/4_Axis_TB6560_CNC_Stepper_Motor_Driver_Board_Contr oller&h=502&w=700&sz=208&tbnid=e9yUXx8rVoKnKM:&tbnh=90&tbnw=125&zoom=1&usg=__5NEnleqPk_8v1Szy6_ykz0rHkio=&docid=ohia-xeZpMSKvM&sa=X&ei=5_1JUtjSHIeI7Ab-0oHwBA&ved=0CDQQ9QEwAQ)

That is the main board I was looking at

Cheers,

Pete

m_c
01-10-2013, 10:49 AM
It's best to start with considering the mechanics.
Do you want to run the standard screws, or convert to ball screws?
Then you need to think about mounting the motors, and if you'll need to gear the motors, which you usually do through pulleys and toothed belts.

Homing on the X-axis is highly recommended so you don't need to manually set the tool offsets at each power on/problem recovery, however on a lathe homing the Z isn't as critical, as you'll usually be working at an offset anyway.

Spindle encoder connection will vary depending on what software you're planning on using to drive the lathe.

Don't touch the TB6560 boards, unless you really like to spend time pulling hair out, and fixing them. Some people do manage to get them working ok for their needs, and don't seem to have any issues, but there are plenty who do. It's far better to spend the extra to start with, and go for individual drives, and breakout board/controller.

Pete92
01-10-2013, 12:55 PM
Hi there,

Thanks for the advice. So to use the breakout board, I will need the BOB itself, 2 stepper motor drivers and a smooth stepper? + all the other bits such as power supplies and things.

The machine is already CNC hardware fitted, just the control board is very dated, which is why I want to modernise.

irving2008
01-10-2013, 01:06 PM
You might want to check what stepper motors are fitted to ensure you get compatible drivers, as you may want to fit more modern motors.

You dont need a smoothstepper unless you plan to drive it from USB or Ethernet. Motion rates/loads on a small lathe IMHO really don't need the pulse rates an SS can support.

A standard lowish cost BOB on the parallel port will be fine, unless you dont have a parallel port.

m_c
01-10-2013, 01:12 PM
It all depends on what is reusable.
What voltage is the existing power supply?
Also, what may skew your choices is do the existing switches/sensors use 5V or 24V?
(i've got no experience of emco stuff, but I'd guess on that size of machine they'll be 5V)

As Irving mentions, you'll want to find out what motors are already fitted. Provided they're 2phase, reusing them won't be an issue, although you may want to consider upgrading them at some point, as more modern motors will have better performance.

Also, how is the spindle powered/controlled?

There are other options than a SS (if you do go SS, get the ESS to avoid usb problems), but you have to be careful to check they support lathe threading

That all might sound a bit daunting, but if you sit down, figure out what you've got (spindle/steppers/sensors), what is needed to power/drive it, and how you'd like to control it, we can point you in the right direction.

Pete92
01-10-2013, 01:31 PM
Well from other people I have talked to the motors are very odd. So I am most likely to replace them for modern stepper motors.

EMCO Compact 5 any good? - Page 2 - Home Model Engine Machinist (http://www.homemodelenginemachinist.com/f38/emco-compact-5-any-good-21823/index2.html)

That is my machine there, there are a few pictures of it. The spindle is totally manually controlled on the machine at the moment, on/off and the speed are controlled by the operator. So it should wire into a new spindle controller easily enough.

Will mach3 accept a homing sensor on the x axis?

Cheers,

Pete

JAZZCNC
01-10-2013, 05:17 PM
Well from other people I have talked to the motors are very odd. So I am most likely to replace them for modern stepper motors.

Ron had the right idea by dumping the whole electronics and motors. I've converted a few small Lathes and usually the only thing worth keeping is the DC spindle Speed controller, which sounds like you don't have one.?

Motors are often underpowered and weedy so for sake £60 for 2 motors it's not worth the not doing if your keeping. If you want to spend some money and get great accuracy and repeatability with closed loop then buy the Leadshine hybrid closed loop stepper system, they come complete with Digital drives and are pretty much plug and play. . . More money but perfect for lathes.

Yes Mach will accept individual inputs for both Home and Limits for upto 6 Axis. Each axis can also share the same Input for Both Home and limit sensors so reducing the amount of inputs you'll need.!

m_c
01-10-2013, 11:31 PM
Have you got any pictures of the control cabinet?

The Spindle motor looks like a DC motor, so it will most likely have it's own dedicated controller, and probably has some way of being automatically controlled.