Retrofitting a MAHO MH600T

Yeah, it always a shame it is so hard to take the machine with you on your travels.
Yes, it is the pump which doest not run, when pressing 3SH1, which made me consider 3F1. It might take some time until I can verify it, but I will let you know, what turned out to be the problem. And thanks for your suggestions for the troubleshooting, I will take those as a starting point.

I wish I had found Marks saga before I finished my Maho MHC700 restoration. Not an obvious place to start looking for a Heidenhain controlled machine. My machine has a TNC 155 retrofitted and you probably have read about it's rebuild on Marks thread. Your TNC 355 is very similar. It just has a bit more memory and speed. So it has a few more machine parameters tacked in the end of the TNC 155 list and probably runs a bit faster.
The one really lucky break I got was the Heidenhain worked perfectly first time. All I had to do was load in the machine parameters and swap it to English. Fortunately I had them on paper tape and hand written in the manual.
But that situation didn't last. Recently it started to get some fold back at the top of the BE411 monitor. Not the end of the world, but I couldn't read the line number in graphics mode, making testing programs a bit difficult. The problem is almost always the electrolytic capacitors so I read up on how to not kill myself changing them. Disconcerting things like putting one hand in your pocket whilst shorting the 22000 volts on the plug on the display tube with the other, so you don't draw the voltage across your heart if you mess up.
There are about 25 of them if you do all of them like I did, and there a few difficulties and traps to know if you want to try it on yours, but it came up perfect. Crisp and clean without doing any adjustments. About $60 Australian from Farnell in the UK. 3 days deliver to Australia. And the capacitors are smaller, have up to 5 times the life even at a much higher temperature rating.
In hindsight it might have been easier to do that on yours to debug the circuits then go to LinuxCNC.
The problem with the Heidenhain is you have a TI processor of about the same era an IBM PC AT with an Intel 80286. 16 bit and about 8MHz. And you are limited to simple pocketing and pecking.
With your setup you have the advantage of updating you PC forever and a wealth of open source programs. To get to the next step I'm going to have to get familiar with Fusion 360 and drip feed. Heidenhain has a nice serial coms program that works for all the machine they ever made Fusion 360 has a post processor file that works for my machine. I've been doing my modelling in SolidWorks for the last 30 years so it's not that big a step.

BTW. On mine, once the 220 volt power is latched on by 19K1, it goes through the 3Q1 circuit breaker, then to the  3F1 pressure switch on the hydraulic pump, then back the the hydraulic pump contactor coil 3K1 and runs the pump. The pump run is very brief as there in no hydraulic accumulator on my machine. It runs a lot longer to release both chucks or the CNC rotary table. The Vogel lubricator also runs straight from 3Q1 also and is actually powered by the 220 volts. So it does a lube cycle every startup, then goes to timer based lubrication cycles. So a dumb system not controlled by the CNC controller.

Cheers,
David

Hi David,

Yes, I read about it in Mark's thread. Having a fully functional machine from the start is indeed quite lucky. It's good to know that electrolytic capacitors are often the issue; I'll keep that in mind when we look at the next old machine to buy and restore.

I did consider keeping the machine in its original state, but in the end, I decided the advanced capabilities and modern control options of LinuxCNC were too appealing to pass up. Call me a masochist, but tackling the challenges was also kind of fun!

I believe our hydraulic setups are quite similar. In our case, the pump is connected to a three-phase 380V power supply via 3Q1, followed by the pressure switch. We also have 5K1 (controlled by the CNC), which then operates 3K1 to turn on the hydraulic pump—only if the spindle is off (1K7 - Hauptantrieb Stop).

For the lubrication system, the computer manages 4K1, which appears to operate the pump at 110V. I am thankfull that the lubricator has not been acting up.
Do you have pictures from your machine?

Cheers,

Sebastian