Retrofitting a 1986 Maho MH400E

RotarySMP wrote: Which ones do you guys use for the little stuff?
Mark

Sometimes even the smallest size won't quite grip the wire, but I also find that at that point the ferrules tend to be too long for the cage-clamps, so I tend to snipa bit off with side cutters, and give them a nip in the middle at the same time.

Once clamped up in the terminal block they grip the wire well anyway.

Opened up that yesterday's present.
The monitor and the keyboard work, just the trackball needs a little attention.
I wondered what this little arrow buttons below the keyboard were for.
The whole thing is electrically height adjustible, yeeaahhh .

Initially I wanted to use the upper part only, now I'm torn.
The bend edge of the housing is a con for installing the push-buttons on the right like Mark did on his console.


I'm about to finish my shopping list.
I decided to not cut off the d-sub-15 connectors but buy 3 counter pieces for the connection to the 7i77.

Hooked up an old Enermax PC PSU to my 250MHz Philips Oszilloscope to measure the ripple on the 5V and 12V DC.
It is not measurable. As it delivers 5,12V an 12.2V without load I will try it as the power source for the MESA and the MAHO-EXE.

Decision made !
A little progress:



I will probably use 230V for the control panel as I don't know the voltage rating for the monitor (nowhere to find) and the internal wiring is already there including a 230V RCD plus Mark has some induction issues on main spindle start on 110V.

Looks like you have more than one MH400 machines. Are you wanting to convert both machines ?
Have used Phillips O-scopes , thought they were decent . Does your Phillips scope have provisions for direct Y axis input ? Could be useful for looking at LS403 scale output .
Thought the spindle motor was 380 volt-3 phase, and Mark had occasional house mains shop feed breaker trip when switching on the Maho main input switch. That may be due to the Maho 3 phase Xfmrs saturating from driving the xfmr lamations ( iron ) into the B-H loop upper knee area. A easy work oround is to start up at a reduced input voltage ,such as two of the three phase input wires having resistors ( stove heating elements - etc ) that are shorted out after the initial turn on..Time wise -- only one cycle of input AC is needed to reset the xfmr iron BH operating point. so the two resistors wattage can be small. What is the measured 3 phase voltage level in your shop ?
hanmon Thanks for sharing an hope to see more
Bob

Got nothing done this weekend.

Hi Hanno, since you are hooking up the EXE to an ATX PSU, is this the same PSU powering the PC MoBo, or a separate one? I tried using an ATX PSU but the Y axis wouldn't respond. Yesterday I reconnected the chinese rail mount 5V PSU, and the machine is "working" as before, so I haven't killed anything yet. A friend is coming over tonight to mill a slot in a broaching bushing, so I won't return to trouble shotting till that is done.

Good score on that Kiosk. Saves you a month at least right there.

I have had occasional (like maybe 3 times in all the 100+ cold starts) breaker trip. As you say it is probably the due to the inrush into those huge transformers. I built a 70VDC PSU with a big Toroidal transfromer a couple of years ago with such inrush protection as you suggested. What is the dowside of just putting up with it tripping a few times per year? It is only on cold start, not when the machine it running. Will this wear out and kill the CB?

I am going to be travelling in Feb, so maybe I find the time then to move my draft "how to convert a MAHO" doc to github, so it can be a collabarative document.
Mark

What is a nothing done weekend ? Just set in a corner an drink beer?

On this side of the big pond -- CB (= circuit breakers ) have design life of use , where use is number of times it disconnects the electrical source from the load .due to a overload. Design overload amps can be a "window " from tiny to a dead short with the unit of time factored into the design. Also ,the design accounts for how much energy (really big Watt- Seconds) the source can deliver. .The biggest wear item in a CB used to be the contacts. Have heard there are breakers that are rated for use as a switch , but I have never seen them. Do know that breakers are made which will accommodate higher short term inrush amps ,such as for motor starting or very old microwave ovens, etc . Might be worth looking at running a separate feed - sub panel - just for the shop or if a replacement ( one that will actually fit ) high inrush breaker is available for your home electrical panel. . Don't void the Home Insurance policy!

"What is the downside of just putting up with it tripping a few times per year? It is only on cold start, not when the machine it running. Will this wear out and kill the CB? " If the frequency of trips increases or it requires several resets per Maho turn on then it's breaker change time.

---

If your name is Bob , or you are asking others in the house to reset the breaker then it is a very real concern !

Any thought of Hanmon loaning you a LS403 read head?

Moving your draft -"How to convert a MAHO" doc to github, so it can be a collaborative document . My thoughts: Pro --- Would give you less hassle with E-mailing the Doc. Provides a second repository site for the concise this is how it has been done.. Cons --- If you could not maintain control of content ,changes/revisions then I see a negative aspect . Not sure if the collaboration from here will cross over to github as much. My thinking is that github is a document repository vers this site being the collaboration site .
But it's your sand box and you should make the rules. If you think it's not working as you want , than add more sand.!

Me I just think what you are doing is great , keep it up.
Bob