Cnc lathe donated


#10

Nice!

I have been looking at possible monitors I have on hand to connect to the RF output.

  1. An old paper white monitor - unfortunately it is 9 pin TTL, not RF input. Maybe could find TTL signals in the lathe and connect direct?

  2. Modern 16" digital TV, which has RF input - but says it only decodes digital (so no PAL or NTSC analog). It does have an AV input, so that could be a possible way.

So no quick connect options from me.

@sjdavies - do we know what format the RF output is - or what digital signals feed that RF converter?


(Stephen Davies) #11

Hi,
I believe it has modulated (TV) and unmodulated (composite) outputs. TV Output has one of the sealed modulators, popular in the ‘80s. Probably on vhf channel 3.


(Stephen Davies) #12

Good news, the stepper driver has been repaired. Both Z-axis drive channels are operational.

Bads news, the reason it blew is because the Z-axis stepper motor has shorted turns in one of its four poles.

We could:

  1. Attempt to locate a replacement motor
  2. Attempt to upgrade the controller and stepper motors to something more modern
  3. Replace steppers with manual controls, i.e. convert lathe to manual operation

To be honest, option 3 looks pretty good to me right now. I don’t require a lathe much and when I do I am only making parts on a one of basis. CNC makes sense when making multiple, identical parts.

Anybody else care to share their thoughts?


(Stephen Davies) #13

Also, lathe serial number is A6A 8405029. This means it was manufactured in May 1984 and was the 29th in the monthly batch.


(Ben Paton) #14

Is there an option for us to use the mechanics as the basis of building our own CNC controller? Ie replace the control motors and build a controller system.


(Stephen Davies) #15

Yes, that was option 2.


(Ben Paton) #16

Cool; I mean I make that statement not quite sure of how big a job that would be so feel free to ignore me.


(Stephen Davies) #17

Option 2 is non-trivial.


#18

web searching suggest MAYBE can get another (prob 2nd hand) stepper. Maybe as getting some odd search results and as Stephen has noted stepper has unusual specs and as controller/firmware is locked down hard to replace with dif spec stepper (unless we do something challenging like scale one axis of EVERY design to match new stepper :slight_smile:

Had heard maybe one more part of lathe is still at the donating organisation - is it possible they (or a kindred body) have a spare stepper as well? Can we ask their parent body ( or Australian org?).


(Stephen Davies) #19

Hi all,
Steve K asked me to do a bit of a write up on what I did to fix the lathes stepper motor control board.

I don’t intend posting it here. The best home for it is on the Emco Users group where there is a bunch of other very useful, related info.

https://groups.io/g/Emco-CNC-Users/files/Emco%20compact%20%205%20cnc%20lathe

Look for the files posted by aushacker.


(Stephen Davies) #20

As things stand the lathe is non operational due to a blown stepper motor.

I am currently negotiating with a gent in the US who has one or two spares. He hasn’t named a price for the motor(s), I get the impression of free to a good home, but we’re trying to work out a way to get them to Australia on the cheap.


(Chris Jones) #21

If the source of spare stepper motors doesn’t work out (or even while you are waiting to find out), please post the specs of the motor, i.e. approximate size, step size, coil resistance and current rating (and inductance if known) as I have a much too large collection of old steppers, mostly of the correct vintage, and I might have something that would do.


(Stephen Davies) #22

Hi Chris,
thanks for your kind offer. Need to wait and see how the US offer pans out.

All,
looks like my contact Dave in the US is coming good with his offer. Expect to have two steppers available for pickup in Ulladulla around the end of the month. Best part is no charge either for the motors, “free to a good home”, or the transport to Australia (Dave’s friends luggage).

If anyone is going to be in the Ulladulla area early November and is willing to pick up the motors could you please let me know via private message?


(Stephen Davies) #23

Hi all,
Dave in the US has come good and there are now two Emco steppers waiting for pickup in Ulladulla. If anyone plans on visiting the area in the next two weeks and is prepared to do a pickup could you please let me know via PM?

Thanks,
Stephen


(Stephen Davies) #24

Current status on this is that the stepper motors are still in Ulladulla. Unfortunately Neville, the keeper of said motors, didn’t end up making a trip to Canberra this week.

@ian has indicated he may be in the area in a fortnight. Will keep you posted.


(Stephen Davies) #25

@RyRyPrime and I attempted to connect @spanner888’s LCD TV to the lathe tonight using composite video. No joy unfortunately. Will try again next week.


(Stephen Davies) #26

Thanks to @spanner888 organising a pickup the stepper motors arrived last Wednesday. I replaced the broken motor and am pleased to report that the lathe now has working X and Z axes.


#27

Yeay! Made anything yet? Photos?


(Stephen Davies) #28

Not yet. Tool changer is still in the cupboard. It needs to be stripped, cleaned and lubricated before being reattached. Once that’s done the question of tooling needs to be addressed.

The automatic tool changer uses carbide inserts. Right now we have a right to left cut tool (facing) and a threading tool. The RL tool is a workhorse and has 1 unchipped end. Don’t imagine the threading tool will get a huge amount of use. It is also chipped on one end. A new LR tool is needed but may be expensive, Emco spares are a high end item and uncommon.

We may want to consider replacing the auto toolchanger with a quick change toolpost (Chinese). The upside would be cheaper, readily available parts. The downside would be manual toolchanges.

Other items on the to do list are
. Dust cover
. Trolley
. Display screen


(Stephen Davies) #29

Progress Report #?

with Ryan’s help connected up an old plasma TV and checked the video was working. Makes it SO much easier to enter CNC programs.

IMG_0318