Building and installing the Clough42 Electronic Leadscrew controller

[northwest]

Yes, I know I am five minutes in to have the CNC lathe up and running but bear with me. I bought the boards and other bits and bobs to install the Clough 42 electronic leadscrew to my Harrison M300 about two years ago, I see no point in rushing :-)
Anyhow with the success of my CNC lathe giving me fresh impetus I called a friend and asked him if he was still messing on with this controller, turned out he is and further, he invited me over to help me with mine. Now, because I like a treat (?) I bought two of these Servo's and controllers 1.2Kw. I have stuck with SZGH company because of their reliability as a company and their support, I WhatsApped them a question on a Sunday and received a reply, not instantly but nevertheless. One for the spindle drive on my CNC Lathe and one for the Leadscrew on the Harrison. Now conscious of the struggle @m_c had with the drive on the lathe I was really apprehensive about using the second on the Leadscrew project, I am not remotely as competent with these things as he is so when my pal said to me to bring the bits over and he would flash the controller with the latest firmware I jumped at the opportunity, the snag is I have to go over tomorrow, which is a bit sudden but I am not going to let the chance slip by. My problem is the connector for the drive, I have put it "somewhere safe" so today I am going to tear the place apart looking for it!
Then I am going to get all the bits together and put them all in one box!

Further updates as we go along.

 

[northwest]

For anyone contemplating this conversion, this is a very good resource and guides you through the connections:

Wiring Everything Together

Lathe electronic leadscrew controller. Contribute to clough42/electronic-leadscrew development by creating an account on GitHub.

github.com

Then of course the Youtube video's by the man himself, this is probably the one I am going to struggle with the most because we are back at that Achilles heel of mine, MATH!

It is number two in quite a list of very informative video's he produced.

 

[northwest]

Made a bit of progress today but to my utter frustration I just cannot find the bloody connector I "put safe" sometime last week, very bloody annoying. Anyhow, lets move on, studying carefully the wiring diagrams on the various websites, one of which I have linked to above I have drawn up in my mind the wiring plan, not a diagram but more a plan of how I am going to approach the different connections as they are spread across the circuits to get the connections to the servo controller, a methodical do_not_deviate_from_the_plan approach is mandatory. I am pretty hopeless at writing things down and run a constant series of plans and drawings in my head, it works for me, mostly. Anyhow, drill a hole in the side of the display unit box:



Those little roatabroach cutters are just magic.

Then prep the socket:


Now into the box:



and it all fits in the space:



Starting to look the part now and starting to pull together the other components:






Connecting using a D sub 15pin connector and I can mount this into the side of the box holding the boards making it easily connectable/disconnectable, I will need to facilitate the 5volt power connector, the servo drive supplies it's own power so no need to accommodate the servo power supply. I will report on how I get on tomorrow.

 

[northwest]

Went over to my pals house yesterday whereupon I had a moment of clarity, I am absolutely going to need to install the rotary encoder connected to the spindle, in my ignorance I had imagined because I have the servomotor with integrated encoder I was all set. Then the penny dropped, I don't need to know where the motor reference is I need to know (or rather the system needs to know) where the spindle is relative to the servo <DOH!> So the next chapter will explain how I did that :-)

 

[Robotstar5]

Industrial robots moved away from external (to the motor) encoders about 40 years ago and have them mounted on the back of the motor.

 

[Dell]

Has the project stalled?
I have ELS on my Myford not just Z axis but X as well because I struggle holding & turning handles for any length of time due to having gout in my hands but I decided to go the Rocketronics controller route because it can not only cut threads in metric, imperial & BA it will do internal, external including taper & multi start plus turn cones, elliptical & of course turn stock to preset size & so much more so keep going it’s worth it.
Dell




My not so large workshop

 

[northwest]

Very nicely done. No, the project hasn't stalled. I stopped as I am:

a) trying to learn how to use my CNC lathe
b) Trying to get the Colchester Master up and running and last but not least
c) get some work out the door and earn a crust

This is all being hampered by the simple fact I am Fsked. I struggle to get up in a morning and at five in the afternoon I am ready for bed. I am trying to build up my "steps" and am up to 6000 regularly now which is a massive step forward. That we have better weather is a positive thing too as I am getting my bike out but going somewhere is great, it is the coming back part that kills me (I hope not in a literal sense). Off out today on my bike so positive and although it's great for my physical well being I have to try to balance this with actual productivity time. If this was easy, everyone would do it and I am painfully conscious not everybody gets the chance.

Lovely workshop by the way, nice and tidy, how it should be. Can't be having this looks like a scrapyard presentation.

 

[addjunkie]

Very nicely done. No, the project hasn't stalled. I stopped as I am:

a) trying to learn how to use my CNC lathe
b) Trying to get the Colchester Master up and running and last but not least
c) get some work out the door and earn a crust

This is all being hampered by the simple fact I am Fsked. I struggle to get up in a morning and at five in the afternoon I am ready for bed. I am trying to build up my "steps" and am up to 6000 regularly now which is a massive step forward. That we have better weather is a positive thing too as I am getting my bike out but going somewhere is great, it is the coming back part that kills me (I hope not in a literal sense). Off out today on my bike so positive and although it's great for my physical well being I have to try to balance this with actual productivity time. If this was easy, everyone would do it and I am painfully conscious not everybody gets the chance.

Lovely workshop by the way, nice and tidy, how it should be. Can't be having this looks like a scrapyard presentation.

Try a power nap at about 2.30, set the alarm or youll sleep through tea. 40 minutes or so, makes for a longer day!

 

[northwest]

Try a power nap at about 2.30, set the alarm or youll sleep through tea. 40 minutes or so, makes for a longer day!

I will give that a try. But for today the reason I was especially Fsked Knackered exhausted was because I hadn't taken any of my medication this morning, I just simply forgot. I am on a warning from Cardiology to not go without for more than 24 hours or it could turn nasty. I went twelve and that was enough. I do have a "system" and prepare it all but I was in a rush and, and...... You know the story I am sure, lesson well and truly learned.

 

[addjunkie]

I will give that a try. But for today the reason I was especially Fsked Knackered exhausted was because I hadn't taken any of my medication this morning, I just simply forgot. I am on a warning from Cardiology to not go without for more than 24 hours or it could turn nasty. I went twelve and that was enough. I do have a "system" and prepare it all but I was in a rush and, and...... You know the story I am sure, lesson well and truly learned.

Least you have an idea why!

 

[tigdlo]

I started mine around August 2019 but didn't install it on my ML7 until last year after breaking a tooth off the spindle gear trying to cut a 1 3/4" 5 TPI backplate for my "big" lathe. Even though it was a temporary bodge job, still running on a breadboard with the wrong transistors, it worked very well.

 

[sako243]

Went over to my pals house yesterday whereupon I had a moment of clarity, I am absolutely going to need to install the rotary encoder connected to the spindle, in my ignorance I had imagined because I have the servomotor with integrated encoder I was all set. Then the penny dropped, I don't need to know where the motor reference is I need to know (or rather the system needs to know) where the spindle is relative to the servo <DOH!> So the next chapter will explain how I did that :-)

As long as there's no slippage between the servo and the spindle then it'll just be a scaling factor. If there's the liklihood of the two getting knocked out of sync then having it on the spindle would be beneficial.

As @Robotstar5 points out most industrial stuff has it built into the motor now. The servo I installed on a guillotine back gauge had this (belt drive to a leadscrew). The original setup was the same albeit with a DC servo and had been that way since new 20 years ago.

 

[David_W]

As long as there's no slippage between the servo and the spindle then it'll just be a scaling factor. If there's the liklihood of the two getting knocked out of sync then having it on the spindle would be beneficial.

As @Robotstar5 points out most industrial stuff has it built into the motor now. The servo I installed on a guillotine back gauge had this (belt drive to a leadscrew). The original setup was the same albeit with a DC servo and had been that way since new 20 years ago.

I might be missing something, but I thought that the servo will be attached to the leadscrew and the encoder needs to be attached to the spindle, with no mechanical connection between them?

 

[sako243]

He'll need an encoder on both if it's to be CNC because it'll need to know where the spindle is with respect to the lead screw.

The servo usually has an encoder built in which is what @Robotstar5 and I were referring to.

Skim re-reading the posts you may be right, the servo motor (assuming it's for the lead screw because I didn't read very thoroughly) will handle it's own position by virtue of having its own integrated encoder. An additional encoder will then be required (unless also driven by a servo) for knowing where the spindle is.

 

[David_W]

Yeah, the joys of ELS is that it just copes with whatever a dumb motor does with the spindle and a reasonably inexpensive addition when you don't need a big servo to drive the spindle

 

[northwest]

Just for clarity, the servo has its own encoder but that will only tell the system where the servo is in relation to itself and not relative to the spindle so I need an encoder on the spindle. This then makes me wonder if the pulley sizes on the motor and leadscrew are going to become an issue. I know they were on the CNC Lathe conversion but @m_c had pre-empted this and told me to make sure the pulleys were the same diameter/tooth count I realise now just how smart a move this was.

Frankly I don't know whether or not I am talking absolute cobblers because I am not smart enough to understand it all so I listen to others who are and make my decisions based on their advice.

 

[northwest]

As long as there's no slippage between the servo and the spindle then it'll just be a scaling factor. If there's the liklihood of the two getting knocked out of sync then having it on the spindle would be beneficial.

The spindle is driven by a 3 horse 3 phase motor and the leadscrew by a gurt big (2 horse) servo.

 

[sako243]

The spindle is driven by a 3 horse 3 phase motor and the leadscrew by a gurt big (2 horse) servo.

So the leadscrew has a servo with encoder?

Then a seperate encoder will be needed for the spindle.

 

[northwest]

So the leadscrew has a servo with encoder?

Then a seperate encoder will be needed for the spindle.

Exactly, I hadn't realised this (I am more 'ammers n spanners) so it was a bit of a disappointment to find I would need an encoder on the spindle. Fortunately I have one left over from the CNC Lathe build so no hanging about waiting one to arrive, I have it and what I really need to work out is how to get a gear onto the spindle and then mount the encoder in the current space under the cover.

 

[sako243]

If that proves difficult what about replacing the spindle drive with a servo motor as well? They're not hugely expensive from Ali express.