Threading with A B phase only?

Actually I have now located the info on the different encoders (Rotary and Linear) all made by Heidenhain and have been today onto Heidenhain UK to check what compatible DRO's and Controllers they have that could take the input of these encoders in order to form a basis for partial CNC operation. How should I think about controlling the thread cutting leadscrew feed motor rotation to match different TPI's on demand? Anyway would love to hear about your final solutions Mtndrew77. Do you live on the Isle Of Wight by any chance (I ask this only because I heard that there was a fellow there who worked on a DIY CNC conversion of an Encomat lathe...). Adam

Below is what I used and approximate cost. I Attached the info I have on the heidenhain encoders. The inverter will run the 5hp
motor on 220v supply and will connect to the mesa spindle interface. The mesa card also has a spindle encoder interface. I connected the a and b phase from the heidenhain rotary encoder and used the balluff proximity switch on the spindle for the index pulse for threading. The balluff sensor is 24v so I had to make a voltage divider to connect it to the mesa card. I also modified the sensor ring so I only get one pulse per rev. Also I have pdf's of the manuals if you need them. Hope that helps




Mesa 7i76e-$200
Huanyang inverter 7,5kw-$350
Wanti steppers and drives-$250
Old Okuma Control Panel -$40
Misc supplies-$200
Time- $1 Crap ton

Very many thanks Mtndrew77! That is very interesting and helpful. Does the result offer all the performance of the original system including being able to command whatever TPI / Pitch mm you need for the leadscrew feed motor rotation to allow thread cutting?

Well actually the result is way more capable than the original. I added a x-axis motor to mine so it has full CNC capabilities now. The original only had one motor for x and z, and you could only execute one program step at a time. To answer your question LinuxCNC can handle any thread pitch. All you need to do is configure it to whatever hardware you decide to use.

My finished pictures are below if you haven't already seen them

forum.linuxcnc.org/show-your-stuff/31744...finished-emcomat-20e

Thanks. Having looked at the Mesa 7176E downloaded support manual from their website, I see that this sort of DIY CNC conversion is way beyond my flight range! I was really hoping to strip out all the control electronics (except the motors and encoders) because the faults preventing operation were never successfully located by the EMCO engineers after many hours of replacing different controller boards etc, and replace entirely with a modern working electrical package. The opportunity to at the same time upgrade to CNC is very appealing. It seems your conversion is quite far from plug&play and that really I need to start by read some beginners' literature!! However, a couple of questions if I may -
1) Of the 4 encoders , the 3 rotary ones are standard TTL square wave output, but the linear LS 303c gives a 11 micro amp sine wave output - did you find the original Emcomat 20E wiring has that sine wave signal pass through a small signal converter box (converting from sign wave to TTL square wave) before entering the main controller box? I cannot find it .
2) How much of the original electronics are you using in your new system - does the Mesa card replace some or all of the the PCB cards in the controller box ? Are all the electrical components listed in pages 72-87 of the Electrical Documentation Edition 94-2-V1 required to be functioning properly?
Kind regards, Adam

1. I attached a picture of the board you are looking for it's located underneath the old control screen. It sits on top of the Cpu board.
This is the board that converts from sine to square wave. I don't currently use mine because it is not really needed with my stepper motors, and the 7i76 only has a spindle encoder interface. LinuxCNC does not support a closed loop stepper system that I know of

2. LinuxCNC and the Mesa Card replace all the old electronics on my machine. I'm still using the old power supply, and some relays
and switches, but that is about it. I'm sure you could still salvage the old VFD and Step motor driver, but for my time and money it was way quicker and easier to replace.

Hope that Helps

Oh I see - Heidenhain signal converter is now a small box about 4" x 2.5" they call EXE101 that converts the signal into TTL - probably in 1992 that did not exist!
I am wondering how helpful you really have the time and/or inclination to be. I mean I suppose how fair is it for me to ask you for your help when you have put so much time and effort already into pioneering the project. In an ideal world I would like a complete step by step guide for an utter novice and I should think that is too much to ask. However I did read in your postings that you were looking for some Multifix toolholders - I do have some spare which i could offer you in compensation for your time! What do you think? Kind regards, Adam

I could send you 2 original swiss ones for the Multifix B...

Well I'm by far no guru, but I will help you when I can. I won't take your holders: plenty of people have helped me for free and its
only fair to pay it forward. I can tell you there really is no easy button with LinuxCNC. You have to put in the time to learn, read, and research. How much time is going to depend on how much you already know. I can't give you a step by step guide, but if you answer the questions below I can help point you in the right direction


What do you want the end result of your build to be?

How much time, and money do you want to spend?

How much do you already know about electronics, computer programming and cnc machining?

OK many thanks.
I want to have my 20E (currently not working) with reliable new electronics performing all functions as originally intended PLUS being able to cut diagonals/tapers, and thus with the ability to do CNC operations as I learn about CNC.

I have plenty of time as I am a 60 year old retiree stockbroker and want a project, although I would like to avoid trying to reinvent the wheel as regards converting this particular lathe! I do not want to spend more than $1500 all in for everything.

I am a hobbyist. I fiddle about with lathes (I have this Encomat and also a Myford S7) and milling (I have a Bridgeport Series 1 and an Aciera F3) in my home workshop entirely self taught, along with a MIG welder and Meddings drill. I am an incompetent but enthusiastic machinist. I am familiar with inverters and motors and used to pulling apart and fixing motors and machines, and am therefore I think able to work my way through basic electronics with a multimeter. I know very little about computer programming albeit I did once embark on trying to learn Java and I have never yet operated a CNC machine!
How's that for madness? Adam