Retrofitting a 1986 Maho MH400E

Bob,

My Maho is not given the name E2, but I know why you ask, and it IS built like the E2's. The difference is that they had by then discontinued the E version, and dropped the 2 in the name as this was no longer an option but standard on all machines. As I mentioned, the vintage of a machine like this is as important as the model, or even more important. Because the differences are so huge between them! Mine also had the 432/10 with the last verison of the software. And an Intel 80386 CPU on it!
To those who doesn't know what we are talking about here: The E2 is an upgraded spindle motor and with a fully controlled VFD drive capable of direct speed control. The drive even have C-axis capabilities (it can be used in a lathe spindle for full C-axis, with position control), and can therefore do rigid tapping. It can also rotate and align the spindle to preppare for a tool change (M19).
This is easily identified by the shape of the spindle motor. If it has rounded edges, like a normal induction motor has, with a fan attached to the axis of the motor, it is an old style. This doesn't have electronic speed control, and needs a lot of gears to be able to change speeds. These motors also was normally the same green (or gray) color as the body of the mill. While the new VFD spindle motors have a separate fan and is black and looks like a big servo motor. And is capable of full speed and position control. It has a very simple 2 speed gear box, to give it high torque at low speeds (50 RPM at the lowest) and a top speed of 5000 RPM. There is a 1024 pulse encoder on the spindle shaft for position control, which is feed to the spindle drive. The drive have an ecoder output that I now have hooked to the 7i77 (for rigid tapping).
I had to fix this drive as the first thing I did when I got the mill. It had experienced exploding electrolytic capacitors that took other components with it (and burned traces on the PCB). And thanks to information I got in the large thread over at PM I was able to fix it. It was also a good thing it was in one of the phase drivers, with many similar sections, with only one of them blown. So I could use the others as referance when fixing it. I have since also had an axis drive blow electrolytic caps. So at that point I changed all caps in all the rest of the drives and power supply. At least the ones that was likely to fail, as they were in the power and switching parts that is what is wearing them out.

My toolchanger will only change tools in the vertical head. I'd have to say thankfully. Because the ones that changes in both spindles are way more complicated, and will be a huge job to retrofit with LinuCNC. The one I have now is way complicated enough for me!

I will definately post configs when I get something to post (so nothing yet!). I know why you ask, and find myself very frustrated by others who isn't posting their configs. Sometimes even after promising to do so, only to forget about it as soon as they get their machines working and no longer frequent this forum. It's understandable you'd want to go out to make chips instead of reading forums. But it is one of the downsides of how thigs work around here.
So..... I can promise I will not forget to post my config files.

BTW; it will be kind of advanced. I have mounted extra encoders on my servos, to use dual encoders for increased speed and accuracy (I have tested it on one axis at one point, and it works).
My Y-axis have a lot of stick-slip as well, so I will need to do something to that. I have started to work on hydraulic pistons under the table for weight relief. But I suspect I have to remove the carriage and do some scraping on the box ways of it too......
But for now I will work to get the ATC to work. It has been kind of a nemesis for meg with this mill. And now that I have found enough other configs to give me a clue on how to proceed I hope to get this milestone done in the near future.
I did find a very similar ATC being controlled by LiunxCNC. And was also able to find the configs..... posted in a Hungarian forum I think it was. To my disappointment it was unreadable to me as all comments was in..... hungarian.... and google translate doesn't work at all with this. I know there are others here reading that in this forum. So they might be able to help. But I have found out how to do it now anyway. So I just have to put in the effort to make it happen.

When I talk about new config I mean the change from 2.7.xx to 2.8.xx (or 2.9 i my case). I understand there are changes there, and my old setup from way back is 2.7.7 of something. In particular with Mesa cards.
So I'm kind of starting from scratch (as I'm unable to find the HD with the last known working LinuxCNC installation on it......crap!).
And I do want the reverse feed and other features in the new version. So this time I intend to set it up with 2.9 (I'd like to make an EDM wire cutter with LinuxCNC at some point, possibly as a unit to set on the table of my Maho, so I need that feature for that).

And NO, I'm not enjoying the snow. I hate it! Thank god it's gone again for now. But I hate it and hope it waits a long time to come back...... My daugter likes it though....

Anders

Anders
Thanks for the update about your machine. I am glad you are still at least working on it. Seems as if some conversions just stop before completion.
Interesting your using two encoders per servo motor. Are you using their signal as feedback to Linux CNC along with the Heidenhain LS403 scales ? Just wondering how you are using the extra feed back loop. My guess would be scales for position loop with extra encoders tied some how into the velocity loop of Linux CNC.

Thanks for the comment about snow ,but I wonder if you are not just trying to make me feel better. Think we could con Chris into room an board plus suntan lotion.
Stay warm
Bob

Hello Chris, Brad,

i watched the video from the TNC Boot.
Has this been filmed only with power to the TNC and the screen connected ?
If not disconnect everything except power and watch the behaviour.

You have got "Stromunterbrechung" on the screen and Numbers in the DROs, so i dont think that there is an bug with the processor or the analog board.
There must be an problem with the internal power supply.

Are you able to monitor the different voltags with an oscilloscop between startup?

Hi Anders,

Thanks for joining in the conversation. Your thread on PR.Mach was one of the big confidence builder which help me take the plunge and buy 1.2 ton of non-functional machine (every one I knew thought I was nuts.).

I'm looking forward to seeing your progress on the machine. Remember in a complicate project, the key is put you hands on it every day. Even if just for a few minutes sitting looking at it and thinking about the next step.
Mark

I'd like to chime in and also cheer Anders on. As Mark said, you do need consistency because difficult things tend to make us all abandon them if they're optional. I copmleted my retrofit under pressure so that took care of the motivation, but it was certainly no fun. However, I'm pretty sure that even if the programming for the ATC is complex, you can still build up the module using small steps. There will be no ready-made configs that will take care of everything, but once you understand how a sample module works, it's going to be much easier to copy and modify parts of it and string your own program together. There's no "stack overflow" way around it in LinuxCNC - you will have to understand what the code is and does to make your machine work the way you want it to. OTOH, it's also not necessary to learn everything from scratch, you can jump to sections in the documentation that are relevant to your needs. At least that's how it worked for me. Good luck!

For those ho need motivation to finish their mahos, just watch how is working with his maho.