Retrofitting a 1986 Maho MH400E

Hi to all, this is one way to fit a pc case and a VFD in the Maho cabinet.
www.google.com/search?q=Coolcube+Maxi&cl...igB&biw=1366&bih=654

Good job on rearranging all those components! That's a nice case as well, what type of motherboard does it take?

Micro atx
John

Yesterday I wired up the 602/1-F EXE I got off ebay into the Y axis. Turns out Heidenhains EXE's models seem to have the same wiring color codes on the six output signals. It was only the power supply wiring which was different on this one.


This one has been wired into the Mesa 7i77 with the differential signals like the 602D.

I could'nt find any info on this 602/1-F model on the internet, and it turns out the difference to the 602D model is the lack of 5x interpolation, so this drops the axis resolution from µm, to 5µm. I got it super cheap, so maybe I'll look for another 602D and replace it. Actually, since I am now only using one channel of the original MAHO EXE board, I might get two more 602D EXEs and and remove the large MAHO board completely.

So did it fix the axis drift problem? Yes it seems to. I ran my clover leaf test for an hour and it looked fine (not an accurate test). Then spent two hours thread milling our my lathe spindle nose protector. Since this involved picking up a nearly finished 40x3.5mm thread, I had to keep running the code, sneaking up on the size in 0.1mm steps. Any drift would have been apparent.

I'll never know whether the y axis drfit was an EMI interference issue solved by the use of differential signals, or a heat sensitive component on the old EXE board, but am pretty happy to have the Maho now moving reliably.
Mark

Hi John,
Did you have to relocate that row of contactors which is now above the PC, or was it already there? It is looking very neat and tidy.
Mark

Originally the internal of the cabinet, beside the cooling unit and the different arrangement of the relay board, was exactly the same with yours.
This is the first thought, but the indramat in this arrangement may have trouble with the hot air from the vfd.

Hi Mark,

the EXE-story seems to be neverending

John,
as you have the cooling unit in the cabinet door the location of the components (VFD, PC) should not make a big difference as it constantly circulates the air. Your second attempt looks really nice and well organized.

Hi Hanno, how is your retrofit progressing?

It doesn't really bother me that the current Y Axis EXE has only 5µm resolution. I am such a beginner at milling that this is not limiting. I am mostly pleased to have the motion stable and predictable.

This is the nose protector for the Boley 4LV, for use with collets. I made a few back plates for the Boley, and this was the test peice for the 40x3.5x55° nose thread. It rotated in the chuck before reaching full depth, so threadmilling on the MAHO was used to finish it.




Mark

Hi Mark
Glad you survived the journey to that land way down under . How are things there? weather, politics, bathroom signage etc. invitations for old style Maori dinner parties?
Since using the two 602EXE have you noticed any noise change in the servo motors at machine idle? My thinking is the differential signals for scale input are a good thing . Glad that it is looking as if the LS scales are not the problem !
Be interested in your thoughts of what is next for the Maho conversion .


Hanmon
What is the latest on your Maho conversion?