where to begin to convert a Delta Tau CNC controller application to Linux CNC

So, it sounds like you could use Linuxcnc in lathe mode, you'll obviously need to get control of the servos and the encoders/linear scales for feedback. Servo tuning will be paramount to the accuracy you need.

Do you run multiple cutting tools ?

The other side of this is you need gcode generation, to take your curves and turn them into something linuxnc can handle ie gcode.

Probably need a custom hal component to run the air bearings. I imagine they need to have positive flow prior to motion, this should be easy to do with hal gui using machine on and mwchine ready hal pins.

Nothing sounds extremely difficult, just labor intensive

Thank you very much for your responses, and thank you for your continuing suggestions!

I did ask the motion controller company today...It is a delta tau, and uses G-codes!

Also, did call Omron's technical assistance, there is a tool using the serial port that is quite complete to take the program off of the machine, and it is more complete, according to Omron, than using hyperterminal, and more detailed from hyperterminal or putty. It has been removed from the listing on their website, but using the search feature, it can be found, if this makes sense.

Will be downloading soon, and will install on a couple of computers. Will also be purchasing a DB-9 to USP cord. Let's hope all works as suggested.

Thank you, again,


david

if you perform this retrofit, LinuxCNC will be the motion controller. Do you know if this machine uses resolvers or linear/rotary or incremental or absolute position devices. encoders ?

Thank you!

Yes, linux CNC will be the motion controller. This machine uses linear encoders, not sure if the air bearing spindle has a rotary encoder.

It is okay for me to write I am ignorant about the machine, and ignorant about Linux CNC; but very willing to learn. Even if slow. I have used linux computers for many years, so familiar with some of the quirks. Ready for the next step.

There are encoders, and there are two types, incremental and absolute. Not sure of the technology on these old encoders, or if they have been upgraded or replaced over time. There are limitations for the old ISA bus computers for data, and encoders with very fine resolutions can create a lot of data for the motion control card/host computer. The reason I believe the machine has encoders is because resolvers don't go down to light waves, or sub-light wave resolutions.

I have personally used US Digital encoders for retrofits, so we have used them, but I don't know about the resolution on this machine.

I do know this: an old dos computer will fail. And it's going to happen some time sooner than later. Corrosion is also a factor. These machines are in California, so limited corrosion.

Thank you very much for your interest and responses!


david

Thank you for your responses!

I have ordered a samsung hard drive to install on a intel i3 ir i5 chip. Get it next week, or by the 15th of the month.

Part of the reason for using Mesa is linux sees them right away, and set up is relatively easy.

The part I do not know how to move forward is creating the application in Linux from nothing. I have performed programming in HTML, and some assembler, so slow, but possible for me. Why I asked about where to start. You will have your suggestions.

I understand the machine has gcodes. ASCII commands, also, they may be the same. Need the program, will share. Could be several weeks...

Yes, multiple tools, and yes, probe for calculating the finished thickness.

The air bearings will run; we will have a low pressure switch to be sure the spindle is turned off prior to the air failing or going too low. Built into every machine I have known with air bearings.

I think your comment: "...just labor intensive" is very right.

As previously written, we cannot rely on the manufacturer--they take too long to get back to me for everything so far, and being self-reliant is probably out best alternative for such an old machine, and why I asked for help to begin with.


Thank You!!!


david

Thank you for your response!

Asking the right question, you will get the right answer.

We have yet to purchase these machines, and hopefully by the end of this year. We have purchased other machines like them in decades past that did not work when we got them, and were big boat anchors. Mostly because they were in other parts of the country, and the company was in trouble!

The next part is to get the program off of the old computer. From there becomes the original reason why I asked for help to begin with...

I don't know how to go from the program on the machine to convert it using Linux CNC, where Linux CNC is the motion controller.

It may seem basic; I am missing the knowledge from where I am to where I want to go--learn about what goes on in the program to make it work. We will have the machine program at some point. Once we have the program, there is a large amount of coding and macros in the program, all put together to make the machine work. However, I am missing the knowledge--the learning of what it takes to put this all together in a form Linux CNC can use using Mesa cards to drive the motors, and use encoder feedback.

Your suggestion?

Just to let you know I am serious, I did purchase the Elegoo arduino most complete starter kit. I have been working through some of the examples. Slow, but actually doing something. I have some idea about programming.

Thank you,

david

I am no expert with machine tools but I think you might start reading the Advanced topics section in the linuxcnc docs about kinematics.
It looks like you have a mill/turn machine with ganged tooling but its hard to understand from the info available.
Then download the ISO on the downloads page and burn it to a USB drive. Boot from this drive and run the live install and explore the many simulations bundled with linuxcnc.  Later you can install the system on the Hard drive from the same USB stick.

Read up on the gcode section. See if you can write a program that takes your curves and output a gcode file. Linuxcnc supports filters (generally written in python) which run on a file when its opened. It may be possible to write a filter that takes your design data as input and convert it to gcode as the file is opened in linuxcnc. You should be able to do all this in a simulation without running a machine.

Then as said share lots of photos of the motors, drives, spindle etc so people here can advise on how best to get linuxcnc to control your hardware.

Thank you for your responses!

It will take me some time to do as you have suggested, however, it is exciting that this is what I am looking for to move forward.

The benefit/work of taking something someone else has done has me confused. With the DIY world of linux and linux CNC, there is more work on our end.

After your response, we have found a company who repairs the Delta Tau motion control cards. I am a little concerned about this because several years ago, I asked about Delta Tau's repair facilities, and the Optoform people said they have sent many cards, "repaired', then returned, not to work.

I have taken written notes, and will be working on your suggestions, one at a time.


Thank You, again,


david